Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to 16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.

--
EA, PV'd

Existential Angst wrote:

Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to 16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.

--
EA, PV'd

The pieces are baked *after* they are sprayed. The parts are cold (room
temp) when sprayed.

In order to powder coat, the object to be coated is sand/beadblasted to an extreme state of cleanliness. It is then
electrostatically charged. Then the powder, which is oppositely charged, is sprayed on to the object. At which time, the object is
rolled into the oven which is then brought up to about 400 degrees F. The temperature depends on which powder is actually used, as
they can have different melting temperatures allowing different color effects to be used. The powder then melts and flows
uniformly. If done correctly, the coating thickness is about .020" thick. The object is then cooled and is ready to use. If you do
not the facility to perform all of these steps, successful coating will not occur.
Steve

"Existential Angst" wrote in message ...
Awl --

I've seen HF's stuff ( http://search.harborfreight.com/cpis...rd=powder+coat ), a bit of Eastwood's site
( http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums that seem to like both diy setups. Apparently any
oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken out, hung, and then sprayed? If the latter, I imagine
you gotta be quick, eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) -- is this because the items are actually sprayed in
the booth and not the oven?

About how hot are the pieces when they are sprayed? I imagine this varies with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to 16 x 48", so I'll proly make my own oven out of
various heating elements, brick, etc.

--
EA, PV'd

I think the unanswered question is this:

Once the powder is transferred to the part, what keeps the powder
attached when the charge is removed, so you can move it to the oven?
Why doesn't the powder drop to the floor immediately?

Steve Lusardi wrote:
In order to powder coat, the object to be coated is sand/beadblasted to
an extreme state of cleanliness. It is then electrostatically charged.
Then the powder, which is oppositely charged, is sprayed on to the
object. At which time, the object is rolled into the oven which is then
brought up to about 400 degrees F. The temperature depends on which
powder is actually used, as they can have different melting temperatures
allowing different color effects to be used. The powder then melts and
flows uniformly. If done correctly, the coating thickness is about .020"
thick. The object is then cooled and is ready to use. If you do not the
facility to perform all of these steps, successful coating will not occur.
Steve

"Existential Angst" wrote in message
...
Awl --
I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla
forums that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they
taken out, hung, and then sprayed? If the latter, I imagine you gotta
be quick, eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/
) -- is this because the items are actually sprayed in the booth and
not the oven?

About how hot are the pieces when they are sprayed? I imagine this
varies with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up
to 16 x 48", so I'll proly make my own oven out of various heating
elements, brick, etc.

--
EA, PV'd

"RBnDFW" wrote in message
...
I think the unanswered question is this:

Once the powder is transferred to the part, what keeps the powder attached
when the charge is removed, so you can move it to the oven?
Why doesn't the powder drop to the floor immediately?

Bingo! What I woulda axed, if my brain were werkin....
--
EA



Steve Lusardi wrote:
In order to powder coat, the object to be coated is sand/beadblasted to
an extreme state of cleanliness. It is then electrostatically charged.
Then the powder, which is oppositely charged, is sprayed on to the
object. At which time, the object is rolled into the oven which is then
brought up to about 400 degrees F. The temperature depends on which
powder is actually used, as they can have different melting temperatures
allowing different color effects to be used. The powder then melts and
flows uniformly. If done correctly, the coating thickness is about .020"
thick. The object is then cooled and is ready to use. If you do not the
facility to perform all of these steps, successful coating will not
occur.
Steve

"Existential Angst" wrote in message
...
Awl --
I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla
forums that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they
taken out, hung, and then sprayed? If the latter, I imagine you gotta
be quick, eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ )
-- is this because the items are actually sprayed in the booth and not
the oven?

About how hot are the pieces when they are sprayed? I imagine this
varies with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to
16 x 48", so I'll proly make my own oven out of various heating
elements, brick, etc.

--
EA, PV'd

"Existential Angst" wrote in message
...
"RBnDFW" wrote in message
...
I think the unanswered question is this:

Once the powder is transferred to the part, what keeps the powder
attached when the charge is removed, so you can move it to the oven?
Why doesn't the powder drop to the floor immediately?

Bingo! What I woulda axed, if my brain were werkin....
--
EA



Steve Lusardi wrote:
In order to powder coat, the object to be coated is sand/beadblasted to
an extreme state of cleanliness. It is then electrostatically charged.
Then the powder, which is oppositely charged, is sprayed on to the
object. At which time, the object is rolled into the oven which is then
brought up to about 400 degrees F. The temperature depends on which
powder is actually used, as they can have different melting temperatures
allowing different color effects to be used. The powder then melts and
flows uniformly. If done correctly, the coating thickness is about .020"
thick. The object is then cooled and is ready to use. If you do not the
facility to perform all of these steps, successful coating will not
occur.
Steve

"Existential Angst" wrote in message
...
Awl --
I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla
forums that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they
taken out, hung, and then sprayed? If the latter, I imagine you gotta
be quick, eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ )
-- is this because the items are actually sprayed in the booth and
not the oven?

About how hot are the pieces when they are sprayed? I imagine this
varies with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up
to 16 x 48", so I'll proly make my own oven out of various heating
elements, brick, etc.

--
EA, PV'd


I think there are different processes. There is a dip powder coating for
fishing jig heads. I think you heat the jig slightly and then dip in the
jar. They heat the jig with an oven or torch.
http://www.tacklewarehouse.com/descpageSIP-SIPP.html is the first link I
found.

Bill McKee wrote:

"Existential Angst" wrote in message
...
"RBnDFW" wrote in message
...
I think the unanswered question is this:

Once the powder is transferred to the part, what keeps the powder
attached when the charge is removed, so you can move it to the oven?
Why doesn't the powder drop to the floor immediately?

Bingo! What I woulda axed, if my brain were werkin....
--
EA



Steve Lusardi wrote:
In order to powder coat, the object to be coated is sand/beadblasted to
an extreme state of cleanliness. It is then electrostatically charged.
Then the powder, which is oppositely charged, is sprayed on to the
object. At which time, the object is rolled into the oven which is then
brought up to about 400 degrees F. The temperature depends on which
powder is actually used, as they can have different melting temperatures
allowing different color effects to be used. The powder then melts and
flows uniformly. If done correctly, the coating thickness is about .020"
thick. The object is then cooled and is ready to use. If you do not the
facility to perform all of these steps, successful coating will not
occur.
Steve

"Existential Angst" wrote in message
...
Awl --
I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla
forums that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they
taken out, hung, and then sprayed? If the latter, I imagine you gotta
be quick, eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ )
-- is this because the items are actually sprayed in the booth and
not the oven?

About how hot are the pieces when they are sprayed? I imagine this
varies with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up
to 16 x 48", so I'll proly make my own oven out of various heating
elements, brick, etc.

--
EA, PV'd


I think there are different processes. There is a dip powder coating for
fishing jig heads. I think you heat the jig slightly and then dip in the
jar. They heat the jig with an oven or torch.
http://www.tacklewarehouse.com/descpageSIP-SIPP.html is the first link I
found.

Electrostatic powder coating. The static charge remains for some time so
the powder continues to cling. Think styrofoam beads.

RBnDFW wrote:
I think the unanswered question is this:

Once the powder is transferred to the part, what keeps the powder
attached when the charge is removed, so you can move it to the oven?
Why doesn't the powder drop to the floor immediately?
The charge is actually IN the powder, and it retains it for quite a
while. You can't touch the work, or bump it into stuff, but you can
bang it around surprisingly much without knocking the powder off.

The powder is totally dry before baking, this is not a wet spray
process, it is a dust process.

Jon

On Dec 1, 7:27*pm, RBnDFW wrote:
I think the unanswered question is this:

Once the powder is transferred to the part, what keeps the powder
attached when the charge is removed, so you can move it to the oven?
Why doesn't the powder drop to the floor immediately?

You do not remove the charge. The powder is not conductive. So even
though it is in contact with the metal, only the small area that
actually contacts the metal loses its charge. The rest of the powder
is still charged.

http://www.finishing.com/Library/pennisi/powder.html

"The powder will remain attached to the part as long as some of the
electrostatic charge remains on the powder. To obtain the final solid,
tough, abrasion resistant coating the powder coated items are placed
in an oven and heated to temperatures that range from 160 to 210
degrees C (depending on the powder)."

Dan

On Dec 1, 6:56*pm, " wrote:
On Dec 1, 7:27*pm, RBnDFW wrote: I think the unanswered question is this:

Once the powder is transferred to the part, what keeps the powder
attached when the charge is removed, so you can move it to the oven?
Why doesn't the powder drop to the floor immediately?

You do not remove the charge. *The powder is not conductive. *So even
though it is in contact with the metal, only the small area that
actually contacts the metal loses its charge. *The rest of the powder
is still charged.

http://www.finishing.com/Library/pennisi/powder.html

"The powder will remain attached to the part as long as some of the
electrostatic charge remains on the powder. To obtain the final solid,
tough, abrasion resistant coating the powder coated items are placed
in an oven and heated to temperatures that range from 160 to 210
degrees C (depending on the powder)."

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Dan

I never really gave this much thought, but powder coating is an awful
lot like laser printing.

On Dec 1, 11:42*am, "Existential Angst"
wrote:
Awl --

I've seen HF's stuff (http://search.harborfreight.com/cpis...word=powde...*
), a bit of Eastwood's site (http://www.eastwood.com/hotcoat-powder-coating.html), and a cupla forums
that seem to like both diy setups. *Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? *If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/) -- *
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to *16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.

--
EA, PV'd

The question still remains: Has anyone tried the do-it-yourself powder
coating stuff from HF or similar? Is it possible to get good results?

On Tue, 1 Dec 2009 11:42:28 -0500, "Existential Angst"
wrote:

Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to 16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.

A caution that probably won't apply to anyone he people with
pacemakers or ICD's might want to steer clear of the DIY powdercoat
guns. They're not mentioned in Medtronic or Boston Sci literature but
they employ high electric fields (up to 50KV) to ionize the powder.

Not saying don't do it, just saying heads up.

Existential Angst wrote:
Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to 16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.


I'll try to answer this as brief as possible.
First just so you have some background I spent 14 years working in a
coating plant that did both liquid and powder coating. Did every job in
the place over the years from hanging parts on the lines to supervisor
including driving the trucks to P/U and deliver the parts.

First powder coating as a process is not hard to do. The trick to the
entire process is really simple. THE PART MUST BE CLEAN!!!!
After that it's a cakewalk. Well maybe a few minor items are a PIA but
money can fix those.

First your talking aluminum. I would rather coat my tongue than aluminum
BUT...
First off - How long do you want the coating to last?
With aluminum this is the BIG problem. Aluminum Oxide forms VERY fast.
This is what causes the coating to fail. So you need to come up with a
cleaning method to remove it. In the plant we used a 5 step process,
First a simple degreasing bath, then through a 4 stage wash rig. First
stage rinsed off the panels with PURE water. Then into an acid wash and
rinse then a phosphate bath. Then through a quick rinse and into the
drying side of the oven. From there they could be handled WITH CLEAN
COTTON GLOVES. Touch the part or let it get dirty and you start over.

Next you hang the parts. The easy way is to drill a hole or holes and
use a steel wire to hang the part. Any tapped holes or unpainted areas
get masked off (Just about anything that is easy to remove can be used,
IF you remove it before curing the powder)

Now you coat the parts.
Here you need a powder gun, The cheap guns work BUT if you plan on doing
many of these items hit an industrial auction and get a REAL powder gun,
Graco, Sames, Norton all make good machines. Make sure you get the
COMPLETE unit, should be the control head, and a fluidized hopper you
put the powder in, plus the gun itself and the cables and color hose.

Powder to match the characteristics you want.
This can get interesting due to all of the different ones out there. ANY
color you like can be made, from Clear to Black, High Gloss to dead
flat, Textures, Hammertone, Mixed colors, Metallics, Candies, you name
it and it's out there.

Powder booth to contain the over spray and reclaim the unused CLEAN
powder. (easy to make one for the parts you list out of cardboard or
light tin)

The racking for the parts, This can range from a single wire to a
complete conveyor system. For many folks the common bakers rack with
steel wheels works well.

The oven. This is the part that kicks most people in the guts. "any oven
can be used" Well yes/NO First you need an oven that holds the internal
temp at the cure point within a few degrees for 20-40 minutes. The
common home gas oven doesn't do that very well. An electric beats it
hands down. Then you need a way to vent any smell/fumes (yes curing
powder does STINK). For the parts you have the easy way out would be an
oven built out of tin with electric oven elements and fiberglass
insulation with a shell of tin. OR you could go with infrared heaters
and a simple insulated tunnel.


As for the process itself.

Hang and clean the part. OR clean it and handle it GENTLY while you hang
it up.

To coat it the part gets grounded to a ground strip through the hanging
wire. The powder goes out of the hopper and picks up a positive
electrostatic charge when it goes through the charging section of the
gun (usually at the very exit point). The powder goes through the air
and settles on the part due to the different charges.

This is the point where the pro gun beats all the home guns. CONTROL,
both in the powder stream, speed of discharge, amount of electrostatic
charge (the typical Sames gun we used put a 150KV charge on the powder,
if you got it close to a ground it would throw a 4" arc!!!) and powder
coat mil thickness. Rule of thumb is that the higher the charge the
better the powder sticks, BUT it also will apply the powder THICKER,
which isn't good. This is where the controls come in. On a good gun you
can adjust the entire process.

YES you can cause all the same things with powder that you can do with
liquid, gobs stuck in the paint, dirt, bugs, runs, drips. BUT prior to
you actually curing that powder you can do one thing you cannot do with
ANY liquid paint, REMOVE THE PROBLEM. Simply grab a VERY filtered air
line and blow the powder off the part and recoat. (once you get the hang
of it you can even do spot touch-ups, blow off JUST the offending item
and even create paint designs with just the air gun.

Now you have a clean part, hanging on a wire, with a nice even coat of
powder on it. PERFECT. OOPS you sneezed....

OK you didn't sneeze this time... Believe it or not it takes a LOT of
force to knock that charged powder off that part if you use a good gun.

Now you transfer the part to the rack and GENTLY roll it into your oven.
OR transfer the part to the rack until you have enough coated to fill
the oven (you want room between parts if they move some but not a lot)

The oven will be PRE-HEATED to the cure temperature. Open the door, load
the oven and close the door.
WHY pre-Heat? Because you want those parts to come up to temp FAST so
the powder cures properly and bonds to the aluminum. Remember that
metals expand when heated, if the powder is already starting to gel as
the expansion occurs it will move with the part. If the powder isn't
starting to gel and the part expands you get micro-fissures in the paint
that let air/moisture in. NOT a good thing. Now for cooling you let them
cool together. The powder will again follow the metal. It will actually
stay in a semi-plastic state for quite a while when it is warm.

DO NOT TOUCH THE WARM PARTS!!!

Use the hanging wires to move them out of the oven to cool. Why not
leave them in the oven till it cools? Because powder CAN also be over
cured. Just like baking cookies, there is a point where the dough
softens, flows out and sets. Then they start to brown. If you leave them
in too long what happens? You get CHARCOAL COOKIES... Powder does almost
the same thing at a molecular level. Properly cured powder will move
with the substrate, I have taken .020 test panels, coated them, bent
them over. Flattened the bend down with a mallet and not had the coating
fail on properly cured powder! OVER cure that same powder and it will
flake off and fail.


You asked about spraying hot parts as well. YES you can do that and we
did that a lot on HEAVY cast parts or on parts where the customer needed
a specific thickness of coating for another purpose. For instance the
E-One company ( http://www.eone.com/sewer_systems/intro/index.htm ) had
us coating the pump housings and parts inside many of the sewage grinder
pumps they built. They wanted a VERY thick coat that would then get
machined flat and used as a gasketing surface. This kept all of the cast
iron housing covered and made those pumps last. To give them the proper
coat we would clean the parts and then pre-heat them up to cure
temperature. Then spray on the powder to build up the thickness. The
heated parts would instantly cause the powder to begin curing and then
we baked them a while longer till we reached a full cure.

This process also works on porous items like cast aluminum or iron
because it out-gasses the part and allows the powder to gel without
having gas bubbles in the coating. On 1/4" it isn't needed.

ANY more questions?


--
Steve W.

Steve W. wrote:
Existential Angst wrote:
Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to 16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.


I'll try to answer this as brief as possible.
First just so you have some background I spent 14 years working in a
coating plant that did both liquid and powder coating. Did every job in
the place over the years from hanging parts on the lines to supervisor
including driving the trucks to P/U and deliver the parts.

First powder coating as a process is not hard to do. The trick to the
entire process is really simple. THE PART MUST BE CLEAN!!!!
After that it's a cakewalk. Well maybe a few minor items are a PIA but
money can fix those.

First your talking aluminum. I would rather coat my tongue than aluminum
BUT...
First off - How long do you want the coating to last?
With aluminum this is the BIG problem. Aluminum Oxide forms VERY fast.
This is what causes the coating to fail. So you need to come up with a
cleaning method to remove it. In the plant we used a 5 step process,
First a simple degreasing bath, then through a 4 stage wash rig. First
stage rinsed off the panels with PURE water. Then into an acid wash and
rinse then a phosphate bath. Then through a quick rinse and into the
drying side of the oven. From there they could be handled WITH CLEAN
COTTON GLOVES. Touch the part or let it get dirty and you start over.

Next you hang the parts. The easy way is to drill a hole or holes and
use a steel wire to hang the part. Any tapped holes or unpainted areas
get masked off (Just about anything that is easy to remove can be used,
IF you remove it before curing the powder)

Now you coat the parts.
Here you need a powder gun, The cheap guns work BUT if you plan on doing
many of these items hit an industrial auction and get a REAL powder gun,
Graco, Sames, Norton all make good machines. Make sure you get the
COMPLETE unit, should be the control head, and a fluidized hopper you
put the powder in, plus the gun itself and the cables and color hose.

Powder to match the characteristics you want.
This can get interesting due to all of the different ones out there. ANY
color you like can be made, from Clear to Black, High Gloss to dead
flat, Textures, Hammertone, Mixed colors, Metallics, Candies, you name
it and it's out there.

Powder booth to contain the over spray and reclaim the unused CLEAN
powder. (easy to make one for the parts you list out of cardboard or
light tin)

The racking for the parts, This can range from a single wire to a
complete conveyor system. For many folks the common bakers rack with
steel wheels works well.

The oven. This is the part that kicks most people in the guts. "any oven
can be used" Well yes/NO First you need an oven that holds the internal
temp at the cure point within a few degrees for 20-40 minutes. The
common home gas oven doesn't do that very well. An electric beats it
hands down. Then you need a way to vent any smell/fumes (yes curing
powder does STINK). For the parts you have the easy way out would be an
oven built out of tin with electric oven elements and fiberglass
insulation with a shell of tin. OR you could go with infrared heaters
and a simple insulated tunnel.


As for the process itself.

Hang and clean the part. OR clean it and handle it GENTLY while you hang
it up.

To coat it the part gets grounded to a ground strip through the hanging
wire. The powder goes out of the hopper and picks up a positive
electrostatic charge when it goes through the charging section of the
gun (usually at the very exit point). The powder goes through the air
and settles on the part due to the different charges.

This is the point where the pro gun beats all the home guns. CONTROL,
both in the powder stream, speed of discharge, amount of electrostatic
charge (the typical Sames gun we used put a 150KV charge on the powder,
if you got it close to a ground it would throw a 4" arc!!!) and powder
coat mil thickness. Rule of thumb is that the higher the charge the
better the powder sticks, BUT it also will apply the powder THICKER,
which isn't good. This is where the controls come in. On a good gun you
can adjust the entire process.

YES you can cause all the same things with powder that you can do with
liquid, gobs stuck in the paint, dirt, bugs, runs, drips. BUT prior to
you actually curing that powder you can do one thing you cannot do with
ANY liquid paint, REMOVE THE PROBLEM. Simply grab a VERY filtered air
line and blow the powder off the part and recoat. (once you get the hang
of it you can even do spot touch-ups, blow off JUST the offending item
and even create paint designs with just the air gun.

Now you have a clean part, hanging on a wire, with a nice even coat of
powder on it. PERFECT. OOPS you sneezed....

OK you didn't sneeze this time... Believe it or not it takes a LOT of
force to knock that charged powder off that part if you use a good gun.

Now you transfer the part to the rack and GENTLY roll it into your oven.
OR transfer the part to the rack until you have enough coated to fill
the oven (you want room between parts if they move some but not a lot)

The oven will be PRE-HEATED to the cure temperature. Open the door, load
the oven and close the door.
WHY pre-Heat? Because you want those parts to come up to temp FAST so
the powder cures properly and bonds to the aluminum. Remember that
metals expand when heated, if the powder is already starting to gel as
the expansion occurs it will move with the part. If the powder isn't
starting to gel and the part expands you get micro-fissures in the paint
that let air/moisture in. NOT a good thing. Now for cooling you let them
cool together. The powder will again follow the metal. It will actually
stay in a semi-plastic state for quite a while when it is warm.

DO NOT TOUCH THE WARM PARTS!!!

Use the hanging wires to move them out of the oven to cool. Why not
leave them in the oven till it cools? Because powder CAN also be over
cured. Just like baking cookies, there is a point where the dough
softens, flows out and sets. Then they start to brown. If you leave them
in too long what happens? You get CHARCOAL COOKIES... Powder does almost
the same thing at a molecular level. Properly cured powder will move
with the substrate, I have taken .020 test panels, coated them, bent
them over. Flattened the bend down with a mallet and not had the coating
fail on properly cured powder! OVER cure that same powder and it will
flake off and fail.


You asked about spraying hot parts as well. YES you can do that and we
did that a lot on HEAVY cast parts or on parts where the customer needed
a specific thickness of coating for another purpose. For instance the
E-One company ( http://www.eone.com/sewer_systems/intro/index.htm ) had
us coating the pump housings and parts inside many of the sewage grinder
pumps they built. They wanted a VERY thick coat that would then get
machined flat and used as a gasketing surface. This kept all of the cast
iron housing covered and made those pumps last. To give them the proper
coat we would clean the parts and then pre-heat them up to cure
temperature. Then spray on the powder to build up the thickness. The
heated parts would instantly cause the powder to begin curing and then
we baked them a while longer till we reached a full cure.

This process also works on porous items like cast aluminum or iron
because it out-gasses the part and allows the powder to gel without
having gas bubbles in the coating. On 1/4" it isn't needed.

ANY more questions?



Very good write up. I would make one addition.
Use a good respirator when working with the powders. They are toxic
until they are cured. Cheap dust masks don't cut it.
Use a vacuum to clean up the area if not recycling powder overspray.
Same goes for your clothes.

Thats why a booth is used as a controlled area. Powder goes back into
the can or into the filter.

Also, if you make your own oven, check the cure temperature of the
powder you plan to use. Harbor Freight powders need a cure temp of 400
degrees F for 20 minutes after powder glosses over.

Good luck

Jim Vrzal
Holiday, Fl.

Don Foreman wrote:

On Tue, 1 Dec 2009 11:42:28 -0500, "Existential Angst"
wrote:

Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to 16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.

A caution that probably won't apply to anyone he people with
pacemakers or ICD's might want to steer clear of the DIY powdercoat
guns. They're not mentioned in Medtronic or Boston Sci literature but
they employ high electric fields (up to 50KV) to ionize the powder.

Not saying don't do it, just saying heads up.

They're high voltage, but the current is so low, I'm not sure there is
much field to worry about.

Steve W. wrote:

ANY more questions?



Nope. You just convinced me not to bother with trying to powder coat
aluminum (specially in a marine enviornment where it really matters).

Stainless, Gunner!

Pete C. wrote:
Don Foreman wrote:
On Tue, 1 Dec 2009 11:42:28 -0500, "Existential Angst"
wrote:

Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to 16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.
A caution that probably won't apply to anyone he people with
pacemakers or ICD's might want to steer clear of the DIY powdercoat
guns. They're not mentioned in Medtronic or Boston Sci literature but
they employ high electric fields (up to 50KV) to ionize the powder.

Not saying don't do it, just saying heads up.

They're high voltage, but the current is so low, I'm not sure there is
much field to worry about.

Not unless your stupid enough to test the voltage by sticking it over
the pacemaker!

I used to demonstrate the voltage on the guns to folks visiting the
plant by arcing it to ground in the booth with the powder OFF. Most of
the better guns allow you to control the voltage, current, powder
deliver, air flow to the hopper from the front panel.


--
Steve W.

cavelamb wrote:
Steve W. wrote:

ANY more questions?



Nope. You just convinced me not to bother with trying to powder coat
aluminum (specially in a marine enviornment where it really matters).

Stainless, Gunner!

Powder would work OK but that first step of cleaning the part is the
problem part. We did a LOT of marine parts for a couple of the big
outfits as well as http://www.taylormadeproducts.com/ (hatches and
window frames)

It can be done but not with the low end stuff.

--
Steve W.

Steve W. wrote:
Existential Angst wrote:
Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to 16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.


I'll try to answer this as brief as possible.
First just so you have some background I spent 14 years working in a
coating plant that did both liquid and powder coating. Did every job in
the place over the years from hanging parts on the lines to supervisor
including driving the trucks to P/U and deliver the parts.

First powder coating as a process is not hard to do. The trick to the
entire process is really simple. THE PART MUST BE CLEAN!!!!
After that it's a cakewalk. Well maybe a few minor items are a PIA but
money can fix those.

First your talking aluminum. I would rather coat my tongue than aluminum
BUT...
First off - How long do you want the coating to last?
With aluminum this is the BIG problem. Aluminum Oxide forms VERY fast.
This is what causes the coating to fail. So you need to come up with a
cleaning method to remove it. In the plant we used a 5 step process,
First a simple degreasing bath, then through a 4 stage wash rig. First
stage rinsed off the panels with PURE water. Then into an acid wash and
rinse then a phosphate bath. Then through a quick rinse and into the
drying side of the oven. From there they could be handled WITH CLEAN
COTTON GLOVES. Touch the part or let it get dirty and you start over.

Next you hang the parts. The easy way is to drill a hole or holes and
use a steel wire to hang the part. Any tapped holes or unpainted areas
get masked off (Just about anything that is easy to remove can be used,
IF you remove it before curing the powder)

Now you coat the parts.
Here you need a powder gun, The cheap guns work BUT if you plan on doing
many of these items hit an industrial auction and get a REAL powder gun,
Graco, Sames, Norton all make good machines. Make sure you get the
COMPLETE unit, should be the control head, and a fluidized hopper you
put the powder in, plus the gun itself and the cables and color hose.

Powder to match the characteristics you want.
This can get interesting due to all of the different ones out there. ANY
color you like can be made, from Clear to Black, High Gloss to dead
flat, Textures, Hammertone, Mixed colors, Metallics, Candies, you name
it and it's out there.

Powder booth to contain the over spray and reclaim the unused CLEAN
powder. (easy to make one for the parts you list out of cardboard or
light tin)

The racking for the parts, This can range from a single wire to a
complete conveyor system. For many folks the common bakers rack with
steel wheels works well.

The oven. This is the part that kicks most people in the guts. "any oven
can be used" Well yes/NO First you need an oven that holds the internal
temp at the cure point within a few degrees for 20-40 minutes. The
common home gas oven doesn't do that very well. An electric beats it
hands down. Then you need a way to vent any smell/fumes (yes curing
powder does STINK). For the parts you have the easy way out would be an
oven built out of tin with electric oven elements and fiberglass
insulation with a shell of tin. OR you could go with infrared heaters
and a simple insulated tunnel.


As for the process itself.

Hang and clean the part. OR clean it and handle it GENTLY while you hang
it up.

To coat it the part gets grounded to a ground strip through the hanging
wire. The powder goes out of the hopper and picks up a positive
electrostatic charge when it goes through the charging section of the
gun (usually at the very exit point). The powder goes through the air
and settles on the part due to the different charges.

This is the point where the pro gun beats all the home guns. CONTROL,
both in the powder stream, speed of discharge, amount of electrostatic
charge (the typical Sames gun we used put a 150KV charge on the powder,
if you got it close to a ground it would throw a 4" arc!!!) and powder
coat mil thickness. Rule of thumb is that the higher the charge the
better the powder sticks, BUT it also will apply the powder THICKER,
which isn't good. This is where the controls come in. On a good gun you
can adjust the entire process.

YES you can cause all the same things with powder that you can do with
liquid, gobs stuck in the paint, dirt, bugs, runs, drips. BUT prior to
you actually curing that powder you can do one thing you cannot do with
ANY liquid paint, REMOVE THE PROBLEM. Simply grab a VERY filtered air
line and blow the powder off the part and recoat. (once you get the hang
of it you can even do spot touch-ups, blow off JUST the offending item
and even create paint designs with just the air gun.

Now you have a clean part, hanging on a wire, with a nice even coat of
powder on it. PERFECT. OOPS you sneezed....

OK you didn't sneeze this time... Believe it or not it takes a LOT of
force to knock that charged powder off that part if you use a good gun.

Now you transfer the part to the rack and GENTLY roll it into your oven.
OR transfer the part to the rack until you have enough coated to fill
the oven (you want room between parts if they move some but not a lot)

The oven will be PRE-HEATED to the cure temperature. Open the door, load
the oven and close the door.
WHY pre-Heat? Because you want those parts to come up to temp FAST so
the powder cures properly and bonds to the aluminum. Remember that
metals expand when heated, if the powder is already starting to gel as
the expansion occurs it will move with the part. If the powder isn't
starting to gel and the part expands you get micro-fissures in the paint
that let air/moisture in. NOT a good thing. Now for cooling you let them
cool together. The powder will again follow the metal. It will actually
stay in a semi-plastic state for quite a while when it is warm.

DO NOT TOUCH THE WARM PARTS!!!

Use the hanging wires to move them out of the oven to cool. Why not
leave them in the oven till it cools? Because powder CAN also be over
cured. Just like baking cookies, there is a point where the dough
softens, flows out and sets. Then they start to brown. If you leave them
in too long what happens? You get CHARCOAL COOKIES... Powder does almost
the same thing at a molecular level. Properly cured powder will move
with the substrate, I have taken .020 test panels, coated them, bent
them over. Flattened the bend down with a mallet and not had the coating
fail on properly cured powder! OVER cure that same powder and it will
flake off and fail.


You asked about spraying hot parts as well. YES you can do that and we
did that a lot on HEAVY cast parts or on parts where the customer needed
a specific thickness of coating for another purpose. For instance the
E-One company ( http://www.eone.com/sewer_systems/intro/index.htm ) had
us coating the pump housings and parts inside many of the sewage grinder
pumps they built. They wanted a VERY thick coat that would then get
machined flat and used as a gasketing surface. This kept all of the cast
iron housing covered and made those pumps last. To give them the proper
coat we would clean the parts and then pre-heat them up to cure
temperature. Then spray on the powder to build up the thickness. The
heated parts would instantly cause the powder to begin curing and then
we baked them a while longer till we reached a full cure.

This process also works on porous items like cast aluminum or iron
because it out-gasses the part and allows the powder to gel without
having gas bubbles in the coating. On 1/4" it isn't needed.

ANY more questions?

Powder coating without spray gun, charges, or oven:

I watched a CalTrans crew today repaint street markings in front of an
intersection. They laid down metal stencils, then used a weedburner type
torch to heat the asphalt inside the letter cutouts. Then white powder
was dusted over the stencil.

"Steve W." wrote in message
...
Existential Angst wrote:
Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be
quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to
16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.


I'll try to answer this as brief as possible.
First just so you have some background I spent 14 years working in a
coating plant that did both liquid and powder coating. Did every job in
the place over the years from hanging parts on the lines to supervisor
including driving the trucks to P/U and deliver the parts.

First powder coating as a process is not hard to do. The trick to the
entire process is really simple. THE PART MUST BE CLEAN!!!!
After that it's a cakewalk. Well maybe a few minor items are a PIA but
money can fix those.

First your talking aluminum. I would rather coat my tongue than aluminum
BUT...
First off - How long do you want the coating to last?
With aluminum this is the BIG problem. Aluminum Oxide forms VERY fast.
This is what causes the coating to fail. So you need to come up with a
cleaning method to remove it. In the plant we used a 5 step process,
First a simple degreasing bath, then through a 4 stage wash rig. First
stage rinsed off the panels with PURE water. Then into an acid wash and
rinse then a phosphate bath. Then through a quick rinse and into the
drying side of the oven. From there they could be handled WITH CLEAN
COTTON GLOVES. Touch the part or let it get dirty and you start over.

Next you hang the parts. The easy way is to drill a hole or holes and
use a steel wire to hang the part. Any tapped holes or unpainted areas
get masked off (Just about anything that is easy to remove can be used,
IF you remove it before curing the powder)

Now you coat the parts.
Here you need a powder gun, The cheap guns work BUT if you plan on doing
many of these items hit an industrial auction and get a REAL powder gun,
Graco, Sames, Norton all make good machines. Make sure you get the
COMPLETE unit, should be the control head, and a fluidized hopper you
put the powder in, plus the gun itself and the cables and color hose.

Powder to match the characteristics you want.
This can get interesting due to all of the different ones out there. ANY
color you like can be made, from Clear to Black, High Gloss to dead
flat, Textures, Hammertone, Mixed colors, Metallics, Candies, you name
it and it's out there.

Powder booth to contain the over spray and reclaim the unused CLEAN
powder. (easy to make one for the parts you list out of cardboard or
light tin)

The racking for the parts, This can range from a single wire to a
complete conveyor system. For many folks the common bakers rack with
steel wheels works well.

The oven. This is the part that kicks most people in the guts. "any oven
can be used" Well yes/NO First you need an oven that holds the internal
temp at the cure point within a few degrees for 20-40 minutes. The
common home gas oven doesn't do that very well. An electric beats it
hands down. Then you need a way to vent any smell/fumes (yes curing
powder does STINK). For the parts you have the easy way out would be an
oven built out of tin with electric oven elements and fiberglass
insulation with a shell of tin. OR you could go with infrared heaters
and a simple insulated tunnel.


As for the process itself.

Hang and clean the part. OR clean it and handle it GENTLY while you hang
it up.

To coat it the part gets grounded to a ground strip through the hanging
wire. The powder goes out of the hopper and picks up a positive
electrostatic charge when it goes through the charging section of the
gun (usually at the very exit point). The powder goes through the air
and settles on the part due to the different charges.

This is the point where the pro gun beats all the home guns. CONTROL,
both in the powder stream, speed of discharge, amount of electrostatic
charge (the typical Sames gun we used put a 150KV charge on the powder,
if you got it close to a ground it would throw a 4" arc!!!) and powder
coat mil thickness. Rule of thumb is that the higher the charge the
better the powder sticks, BUT it also will apply the powder THICKER,
which isn't good. This is where the controls come in. On a good gun you
can adjust the entire process.

YES you can cause all the same things with powder that you can do with
liquid, gobs stuck in the paint, dirt, bugs, runs, drips. BUT prior to
you actually curing that powder you can do one thing you cannot do with
ANY liquid paint, REMOVE THE PROBLEM. Simply grab a VERY filtered air
line and blow the powder off the part and recoat. (once you get the hang
of it you can even do spot touch-ups, blow off JUST the offending item
and even create paint designs with just the air gun.

Now you have a clean part, hanging on a wire, with a nice even coat of
powder on it. PERFECT. OOPS you sneezed....

OK you didn't sneeze this time... Believe it or not it takes a LOT of
force to knock that charged powder off that part if you use a good gun.

Now you transfer the part to the rack and GENTLY roll it into your oven.
OR transfer the part to the rack until you have enough coated to fill
the oven (you want room between parts if they move some but not a lot)

The oven will be PRE-HEATED to the cure temperature. Open the door, load
the oven and close the door.
WHY pre-Heat? Because you want those parts to come up to temp FAST so
the powder cures properly and bonds to the aluminum. Remember that
metals expand when heated, if the powder is already starting to gel as
the expansion occurs it will move with the part. If the powder isn't
starting to gel and the part expands you get micro-fissures in the paint
that let air/moisture in. NOT a good thing. Now for cooling you let them
cool together. The powder will again follow the metal. It will actually
stay in a semi-plastic state for quite a while when it is warm.

DO NOT TOUCH THE WARM PARTS!!!

Use the hanging wires to move them out of the oven to cool. Why not
leave them in the oven till it cools? Because powder CAN also be over
cured. Just like baking cookies, there is a point where the dough
softens, flows out and sets. Then they start to brown. If you leave them
in too long what happens? You get CHARCOAL COOKIES... Powder does almost
the same thing at a molecular level. Properly cured powder will move
with the substrate, I have taken .020 test panels, coated them, bent
them over. Flattened the bend down with a mallet and not had the coating
fail on properly cured powder! OVER cure that same powder and it will
flake off and fail.


You asked about spraying hot parts as well. YES you can do that and we
did that a lot on HEAVY cast parts or on parts where the customer needed
a specific thickness of coating for another purpose. For instance the
E-One company ( http://www.eone.com/sewer_systems/intro/index.htm ) had
us coating the pump housings and parts inside many of the sewage grinder
pumps they built. They wanted a VERY thick coat that would then get
machined flat and used as a gasketing surface. This kept all of the cast
iron housing covered and made those pumps last. To give them the proper
coat we would clean the parts and then pre-heat them up to cure
temperature. Then spray on the powder to build up the thickness. The
heated parts would instantly cause the powder to begin curing and then
we baked them a while longer till we reached a full cure.

This process also works on porous items like cast aluminum or iron
because it out-gasses the part and allows the powder to gel without
having gas bubbles in the coating. On 1/4" it isn't needed.

ANY more questions?

Two:
Is there an exam?
Do I get college credit?
Good post.

Why does the oxide of aluminum cause problems for powder coating? It's
electrical conductivity is much lower than aluminum (mebbe even an
insulator?), but that shouldn't affect the static electricity effect, unless
alum oxide in fact affects that as well.

Speaking of alum oxide/powder coating, I guess that's why god invented
anodizing.
Which is another option.

That was cool, machining the powder coat itself! Super-neat! Some creative
engineers, on that one!
--
EA



--
Steve W.

Existential Angst wrote:


Two:
Is there an exam?
Do I get college credit?
Good post.

Why does the oxide of aluminum cause problems for powder coating? It's
electrical conductivity is much lower than aluminum (mebbe even an
insulator?), but that shouldn't affect the static electricity effect, unless
alum oxide in fact affects that as well.

The insulating properties are not the problem. It is that the oxide
coating acts as a contaminant and prevents a good bond between the
powder and material. Then the paint fails.
Same problem with chrome plating on aluminum.


Speaking of alum oxide/powder coating, I guess that's why god invented
anodizing.
Which is another option.

Yup, and it's a better one for some applications.


That was cool, machining the powder coat itself! Super-neat! Some creative
engineers, on that one!

They picked up that trick from one of our other customers. Small outfit
called GE Turbine Systems. We coated ALL of the shaft seals used on the
various turbines they made for about 10 years. In that case we used a
special powder that provided insulation properties for the shaft.

We also did some parts for Raymond Corp. (fork lift parts) Those were
interesting. The powder was a special high temp cured nylon blend. Cure
temp was 650 degrees. Those parts had to be preheated, coated then
cured. ALL of this had to be done HOT. These were done in a batch oven.
You would hang the parts, let them get HOT, then open the oven door,
grab a couple parts, close the door, spray them, open the door, then
hang them back up. Repeat until you finished the batch.
These parts and items like the seals and some medical items we did were
done by two people. We also were the ones who taught all the other
sprayers the ropes and did all the gun maintainance as well.

AHH the good old days.....

--
Steve W.

Steve W. wrote:
cavelamb wrote:
Steve W. wrote:
ANY more questions?


Nope. You just convinced me not to bother with trying to powder coat
aluminum (specially in a marine environment where it really matters).

Stainless, Gunner!

Powder would work OK but that first step of cleaning the part is the
problem part. We did a LOT of marine parts for a couple of the big
outfits as well as http://www.taylormadeproducts.com/ (hatches and
window frames)

It can be done but not with the low end stuff.


No, this is a fitting that has a pin that fits into a socket on deck.

I suspect powder coating will get chipped, and in a salt water environment
aluminum would corrode away rather quickly.


I've never had the chance to machine stainless - or any steel for that matter.
I've whittled aluminum with a mill though, and could make what I needed.
So the idea of making parts from stainless is kind of over the top for me.
I honestly don't know how hard it is to do, or how long it would take.
But if I have the choice - all other things being equal...

Like Forest Gump always said, "One less thing to worry about".

On Wed, 02 Dec 2009 12:18:02 -0600, cavelamb
wrote:

Steve W. wrote:

ANY more questions?



Nope. You just convinced me not to bother with trying to powder coat
aluminum (specially in a marine enviornment where it really matters).

Stainless, Gunner!


You got it.

Gunner

"Aren't cats Libertarian? They just want to be left alone.
I think our dog is a Democrat, as he is always looking for a handout"
Unknown Usnet Poster

Heh, heh, I'm pretty sure my dog is a liberal - he has no balls.
Keyton

On Wed, 02 Dec 2009 11:03:01 -0600, "Pete C."
wrote:


Don Foreman wrote:

On Tue, 1 Dec 2009 11:42:28 -0500, "Existential Angst"
wrote:

Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to 16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.

A caution that probably won't apply to anyone he people with
pacemakers or ICD's might want to steer clear of the DIY powdercoat
guns. They're not mentioned in Medtronic or Boston Sci literature but
they employ high electric fields (up to 50KV) to ionize the powder.

Not saying don't do it, just saying heads up.

They're high voltage, but the current is so low, I'm not sure there is
much field to worry about.

I'm thinking E-field (volts per meter), not H field. The current is
microamperes. But it's a DC field so I'm probably being
over-conservative. The voltage is typically developed by a Villard
cascade or Cockcroft-Walton multiplier, both of which usually have
enough capacitance in the string to not have much ripple.

On Wed, 02 Dec 2009 15:37:56 -0500, "Steve W."
wrote:

Pete C. wrote:
Don Foreman wrote:
On Tue, 1 Dec 2009 11:42:28 -0500, "Existential Angst"
wrote:

Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to 16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.
A caution that probably won't apply to anyone he people with
pacemakers or ICD's might want to steer clear of the DIY powdercoat
guns. They're not mentioned in Medtronic or Boston Sci literature but
they employ high electric fields (up to 50KV) to ionize the powder.

Not saying don't do it, just saying heads up.

They're high voltage, but the current is so low, I'm not sure there is
much field to worry about.

Not unless your stupid enough to test the voltage by sticking it over
the pacemaker!

I'm not quite that stupid, though dissenting opinion is probably
available.

Not understanding fields or electronics certainly does not imply
stupidity, but disdaining guidance from those who do could be foolish
for those whose lives depend on having their implanted electronics
work without fault.

Electronic devices can be affected by both E-fields and H-fields.
E-fields are due entirely to voltage regardless of current. H-fields
(magnetic) are due to current regardless of voltage. Frequency is a
factor with both. We're talking near fields here, not far fields as in
radiation where alternating H-fields and E-fields are causally linked
by the characteristic impedance of free space or the medium at issue
per Maxwell's vector calculus differential equations.

One medical device mfr's spec for E-field is 1000 volts/meter. An
electrode at 50KV at arm's length can easily produce an E-field well
in excess of 1000 volts/meter.

I'll say again that I do not mean to be alarmist here. I'm a bit
chicken about getting kicked in the chest by the 750-volt 42-joule
mule that resides near my collarbone, but that's just ol'candyass me.
I don't hesitate to MIG weld because I know the H fields are within
limits if I dress the leads carefully. I know this because I measured
them pre-implant. I'm still a bit antsy about TIG with HV HF start
because of my E-field measurements last January. Making a Faraday
cage garment is on my ta-do list.

"Steve W." wrote in message
...
Existential Angst wrote:


Two:
Is there an exam?
Do I get college credit?
Good post.

Why does the oxide of aluminum cause problems for powder coating? It's
electrical conductivity is much lower than aluminum (mebbe even an
insulator?), but that shouldn't affect the static electricity effect,
unless
alum oxide in fact affects that as well.

The insulating properties are not the problem. It is that the oxide
coating acts as a contaminant and prevents a good bond between the
powder and material. Then the paint fails.
Same problem with chrome plating on aluminum.

I can see Al2O3 being a problem for chrome plating, which depends on where
materials fall in the chemical "emf series", but it is less clear why such a
stable compound, useful in its own right, could not be powder coated.
Surely Al2O3 can be *painted*, right? Epoxied? Glued?

Seems to me it should be powder coat-able, which is, in essence, a kind of
melted polymer/paint?
Not argering, just thinking out loud.

From what you describe, it seems like there are various chemical
configurations for powder coats beyond simple pigments, for different
applications/properties -- none for oxided alum, or even anodized alum?
--
EA





Speaking of alum oxide/powder coating, I guess that's why god invented
anodizing.
Which is another option.

Yup, and it's a better one for some applications.


That was cool, machining the powder coat itself! Super-neat! Some
creative
engineers, on that one!

They picked up that trick from one of our other customers. Small outfit
called GE Turbine Systems. We coated ALL of the shaft seals used on the
various turbines they made for about 10 years. In that case we used a
special powder that provided insulation properties for the shaft.

We also did some parts for Raymond Corp. (fork lift parts) Those were
interesting. The powder was a special high temp cured nylon blend. Cure
temp was 650 degrees. Those parts had to be preheated, coated then
cured. ALL of this had to be done HOT. These were done in a batch oven.
You would hang the parts, let them get HOT, then open the oven door,
grab a couple parts, close the door, spray them, open the door, then
hang them back up. Repeat until you finished the batch.
These parts and items like the seals and some medical items we did were
done by two people. We also were the ones who taught all the other
sprayers the ropes and did all the gun maintainance as well.

AHH the good old days.....

--
Steve W.

"Don Foreman" wrote in message
...
On Wed, 02 Dec 2009 15:37:56 -0500, "Steve W."
wrote:

Pete C. wrote:
Don Foreman wrote:
On Tue, 1 Dec 2009 11:42:28 -0500, "Existential Angst"
wrote:

Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla
forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they
taken
out, hung, and then sprayed? If the latter, I imagine you gotta be
quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/
) --
is this because the items are actually sprayed in the booth and not
the
oven?

About how hot are the pieces when they are sprayed? I imagine this
varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up
to 16
x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.
A caution that probably won't apply to anyone he people with
pacemakers or ICD's might want to steer clear of the DIY powdercoat
guns. They're not mentioned in Medtronic or Boston Sci literature but
they employ high electric fields (up to 50KV) to ionize the powder.

Not saying don't do it, just saying heads up.

They're high voltage, but the current is so low, I'm not sure there is
much field to worry about.

Not unless your stupid enough to test the voltage by sticking it over
the pacemaker!

I'm not quite that stupid, though dissenting opinion is probably
available.

Not understanding fields or electronics certainly does not imply
stupidity, but disdaining guidance from those who do could be foolish
for those whose lives depend on having their implanted electronics
work without fault.

Electronic devices can be affected by both E-fields and H-fields.
E-fields are due entirely to voltage regardless of current. H-fields
(magnetic) are due to current regardless of voltage. Frequency is a
factor with both. We're talking near fields here, not far fields as in
radiation where alternating H-fields and E-fields are causally linked
by the characteristic impedance of free space or the medium at issue
per Maxwell's vector calculus differential equations.

One medical device mfr's spec for E-field is 1000 volts/meter. An
electrode at 50KV at arm's length can easily produce an E-field well
in excess of 1000 volts/meter.

I'll say again that I do not mean to be alarmist here. I'm a bit
chicken about getting kicked in the chest by the 750-volt 42-joule
mule that resides near my collarbone, but that's just ol'candyass me.

Heh, be nice to the missus, lest she start powder-coating as a hobby, with
an evil grin on her face.
--
EA


I don't hesitate to MIG weld because I know the H fields are within
limits if I dress the leads carefully. I know this because I measured
them pre-implant. I'm still a bit antsy about TIG with HV HF start
because of my E-field measurements last January. Making a Faraday
cage garment is on my ta-do list.

Don Foreman wrote:

Not unless your stupid enough to test the voltage by sticking it over
the pacemaker!

I'm not quite that stupid, though dissenting opinion is probably
available.

Not understanding fields or electronics certainly does not imply
stupidity, but disdaining guidance from those who do could be foolish
for those whose lives depend on having their implanted electronics
work without fault.

Electronic devices can be affected by both E-fields and H-fields.
E-fields are due entirely to voltage regardless of current. H-fields
(magnetic) are due to current regardless of voltage. Frequency is a
factor with both. We're talking near fields here, not far fields as in
radiation where alternating H-fields and E-fields are causally linked
by the characteristic impedance of free space or the medium at issue
per Maxwell's vector calculus differential equations.

One medical device mfr's spec for E-field is 1000 volts/meter. An
electrode at 50KV at arm's length can easily produce an E-field well
in excess of 1000 volts/meter.

I'll say again that I do not mean to be alarmist here. I'm a bit
chicken about getting kicked in the chest by the 750-volt 42-joule
mule that resides near my collarbone, but that's just ol'candyass me.
I don't hesitate to MIG weld because I know the H fields are within
limits if I dress the leads carefully. I know this because I measured
them pre-implant. I'm still a bit antsy about TIG with HV HF start
because of my E-field measurements last January. Making a Faraday
cage garment is on my ta-do list.

The thing is that the design of the gun shields the user from the
effects. On the pro guns the guns grip is coupled to the system to
prevent the user from having problems.

While in operation there is no arcing or any other discharge. Believe me
you do NOT want an arc with all the explosive powder dust in the air,
Seen the powder ignite twice. Not pretty...

Don't worry about the implant. You WILL KNOW if it trips. I know about 3
people who have them and when they fire it's REALLY obvious. Maybe it's
the "HOLY FU&*" you hear from them or the instant grabbing of the chest
and the panting when they try to breath...

--
Steve W.

Existential Angst wrote:
"Steve W." wrote in message
...
Existential Angst wrote:

Two:
Is there an exam?
Do I get college credit?
Good post.

Why does the oxide of aluminum cause problems for powder coating? It's
electrical conductivity is much lower than aluminum (mebbe even an
insulator?), but that shouldn't affect the static electricity effect,
unless
alum oxide in fact affects that as well.
The insulating properties are not the problem. It is that the oxide
coating acts as a contaminant and prevents a good bond between the
powder and material. Then the paint fails.
Same problem with chrome plating on aluminum.

I can see Al2O3 being a problem for chrome plating, which depends on where
materials fall in the chemical "emf series", but it is less clear why such a
stable compound, useful in its own right, could not be powder coated.
Surely Al2O3 can be *painted*, right? Epoxied? Glued?

The oxide forms a layer on the aluminum which acts almost like you
coated the part with some dust prior to coating.
The way the powder bonds is interesting.


Seems to me it should be powder coat-able, which is, in essence, a kind of
melted polymer/paint?
Not argering, just thinking out loud.

From what you describe, it seems like there are various chemical
configurations for powder coats beyond simple pigments, for different
applications/properties -- none for oxided alum, or even anodized alum?

There are literally thousands of different chemical blends for powder
coating.
For instance lets say you desire a flat black coating 1 mil thick.
What UV stability do you need?
Will the part be inside or outside?
What final surface finish do you wish, smooth, pebbled, sand textured?
Does the coating need to be temperature resistant?, How many degrees?
What temperature will the substrate withstand and for how long?
What wear characteristics do you need?
Electrical Characteristics? Gloss retention?
Fade resistance?

These are just a few things that you decide prior to making the blends.
All of them have to be determined PRIOR to producing the powder. They
cannot be changed later, Unlike a liquid paint which you can add a pearl
or a flatting agent or a gloss additive or whatever.


--
Steve W.

On Thu, 03 Dec 2009 11:53:24 -0500, "Steve W."
wrote:



The thing is that the design of the gun shields the user from the
effects. On the pro guns the guns grip is coupled to the system to
prevent the user from having problems.

While in operation there is no arcing or any other discharge. Believe me
you do NOT want an arc with all the explosive powder dust in the air,
Seen the powder ignite twice. Not pretty...

Don't worry about the implant. You WILL KNOW if it trips. I know about 3
people who have them and when they fire it's REALLY obvious. Maybe it's
the "HOLY FU&*" you hear from them or the instant grabbing of the chest
and the panting when they try to breath...

I'm highly motivated to skip that experience.

"Existential Angst" wrote in message
...
Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be quick,
eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to
16 x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.

--
EA, PV'd




Eastwood ( http://www.eastwood.com/hotcoat-powder-coating.html ) also has a
good line of hot coat guns and powder. Their forums helped me out quite a
bit when I first started too.

"Rhon Wite" wrote in message
ter.com...

"Existential Angst" wrote in message
...
Awl --

I've seen HF's stuff (
http://search.harborfreight.com/cpis...rd=powder+coat
), a bit of Eastwood's site (
http://www.eastwood.com/hotcoat-powder-coating.html ), and a cupla forums
that seem to like both diy setups. Apparently any oven will do.

Cupla Q's:

Do you spray the items while they're still in the oven, or are they taken
out, hung, and then sprayed? If the latter, I imagine you gotta be
quick, eh?
I notice that suppliers distinguish between the oven and the booth
(http://www.sprayboothsupplies.com/ba...-spray-booths/ ) --
is this because the items are actually sprayed in the booth and not the
oven?

About how hot are the pieces when they are sprayed? I imagine this varies
with specific coatings.

If I fool around with powder coating, I will need to do 1/4" alum, up to
16 x 48", so I'll proly make my own oven out of various heating elements,
brick, etc.

--
EA, PV'd




Eastwood ( http://www.eastwood.com/hotcoat-powder-coating.html ) also has
a good line of hot coat guns and powder. Their forums helped me out quite
a bit when I first started too.

or try here http://www.caswellplating.com/index.html

On Fri, 04 Dec 2009 00:08:36 -0600, Don Foreman
wrote:

On Thu, 03 Dec 2009 11:53:24 -0500, "Steve W."
wrote:



The thing is that the design of the gun shields the user from the
effects. On the pro guns the guns grip is coupled to the system to
prevent the user from having problems.

While in operation there is no arcing or any other discharge. Believe me
you do NOT want an arc with all the explosive powder dust in the air,
Seen the powder ignite twice. Not pretty...

Don't worry about the implant. You WILL KNOW if it trips. I know about 3
people who have them and when they fire it's REALLY obvious. Maybe it's
the "HOLY FU&*" you hear from them or the instant grabbing of the chest
and the panting when they try to breath...

I'm highly motivated to skip that experience.

Been following this part of the discussion only tenuously, but I just
now read an article in New Scientist about the effect of the current
crop of tiny headphones on pacemakers. Since I don't know if
non-subbers can access this, I'll risk some copyright issues while
exercising the "fair use" clause; to wit:


People with pacemakers know to keep magnets and electronic devices,
such as cellphones, away from the implant to avoid interference. But
now it seems even the tiny magnets in headphones pose a risk.

It's still safe to use them, says Kevin Fu at the University of
Massachusetts Amherst, who carried out the study. Just don't keep them
in breast pockets.

Fu and colleagues tested eight different headphones by holding them
near the implants of 100 people. They found that in nearly a third of
cases the magnets interfered with the device (Heart Rhythm, DOI:
10.1016/j.hrthm.2009.07.003).

Headphones containing neodymium were the most problematic, as the
magnetic fields generated were very strong for the headphones' size,
says Fu.


http://www.newscientist.com/article/...acemakers.html

FWIW

Joe

On Fri, 04 Dec 2009 12:22:38 -0500, Joe wrote:

On Fri, 04 Dec 2009 00:08:36 -0600, Don Foreman
wrote:

On Thu, 03 Dec 2009 11:53:24 -0500, "Steve W."
wrote:



The thing is that the design of the gun shields the user from the
effects. On the pro guns the guns grip is coupled to the system to
prevent the user from having problems.

While in operation there is no arcing or any other discharge. Believe me
you do NOT want an arc with all the explosive powder dust in the air,
Seen the powder ignite twice. Not pretty...

Don't worry about the implant. You WILL KNOW if it trips. I know about 3
people who have them and when they fire it's REALLY obvious. Maybe it's
the "HOLY FU&*" you hear from them or the instant grabbing of the chest
and the panting when they try to breath...

I'm highly motivated to skip that experience.

Been following this part of the discussion only tenuously, but I just
now read an article in New Scientist about the effect of the current
crop of tiny headphones on pacemakers. Since I don't know if
non-subbers can access this, I'll risk some copyright issues while
exercising the "fair use" clause; to wit:


People with pacemakers know to keep magnets and electronic devices,
such as cellphones, away from the implant to avoid interference. But
now it seems even the tiny magnets in headphones pose a risk.

It's still safe to use them, says Kevin Fu at the University of
Massachusetts Amherst, who carried out the study. Just don't keep them
in breast pockets.

Fu and colleagues tested eight different headphones by holding them
near the implants of 100 people. They found that in nearly a third of
cases the magnets interfered with the device (Heart Rhythm, DOI:
10.1016/j.hrthm.2009.07.003).

Headphones containing neodymium were the most problematic, as the
magnetic fields generated were very strong for the headphones' size,
says Fu.


http://www.newscientist.com/article/...acemakers.html

FWIW

Joe

Amazing what crap poses and passes as science these days. Holding
headphones near the implants of 100 people to see how many malfunction
is an experiment a dim adolescent could do if she could recruit enough
implanted fools to assist.

The safe limit specified by one ICD mfr for static (DC) B-field is 1
millitesla, and B-fields are easily measured.

"Don Foreman" wrote in message
...
On Fri, 04 Dec 2009 12:22:38 -0500, Joe wrote:

On Fri, 04 Dec 2009 00:08:36 -0600, Don Foreman
wrote:

On Thu, 03 Dec 2009 11:53:24 -0500, "Steve W."
wrote:



The thing is that the design of the gun shields the user from the
effects. On the pro guns the guns grip is coupled to the system to
prevent the user from having problems.

While in operation there is no arcing or any other discharge. Believe me
you do NOT want an arc with all the explosive powder dust in the air,
Seen the powder ignite twice. Not pretty...

Don't worry about the implant. You WILL KNOW if it trips. I know about 3
people who have them and when they fire it's REALLY obvious. Maybe it's
the "HOLY FU&*" you hear from them or the instant grabbing of the chest
and the panting when they try to breath...

I'm highly motivated to skip that experience.

Been following this part of the discussion only tenuously, but I just
now read an article in New Scientist about the effect of the current
crop of tiny headphones on pacemakers. Since I don't know if
non-subbers can access this, I'll risk some copyright issues while
exercising the "fair use" clause; to wit:


People with pacemakers know to keep magnets and electronic devices,
such as cellphones, away from the implant to avoid interference. But
now it seems even the tiny magnets in headphones pose a risk.

It's still safe to use them, says Kevin Fu at the University of
Massachusetts Amherst, who carried out the study. Just don't keep them
in breast pockets.

Fu and colleagues tested eight different headphones by holding them
near the implants of 100 people. They found that in nearly a third of
cases the magnets interfered with the device (Heart Rhythm, DOI:
10.1016/j.hrthm.2009.07.003).

Headphones containing neodymium were the most problematic, as the
magnetic fields generated were very strong for the headphones' size,
says Fu.


http://www.newscientist.com/article/...acemakers.html

FWIW

Joe

Amazing what crap poses and passes as science these days. Holding
headphones near the implants of 100 people to see how many malfunction
is an experiment a dim adolescent could do if she could recruit enough
implanted fools to assist.

Well, give those dim adolescents a PhD!
Seems like they're more on the ball than, oh, let's see, Fleischman and Pons
(Cold Fusion).....
Or fukn Watson, who simply pirated DNA results, and stole the Nobel from
Linus Pauling....

Simple science is not nec. bad science.
Sometimes simple is simply elegant.... well, at least according to
Einstein.
--
EA


The safe limit specified by one ICD mfr for static (DC) B-field is 1
millitesla, and B-fields are easily measured.

cavelamb wrote in
m:

Steve W. wrote:
cavelamb wrote:
Steve W. wrote:
ANY more questions?


Nope. You just convinced me not to bother with trying to powder
coat aluminum (specially in a marine environment where it really
matters).

Stainless, Gunner!

Powder would work OK but that first step of cleaning the part is the
problem part. We did a LOT of marine parts for a couple of the big
outfits as well as http://www.taylormadeproducts.com/ (hatches and
window frames)

It can be done but not with the low end stuff.


No, this is a fitting that has a pin that fits into a socket on deck.

I suspect powder coating will get chipped, and in a salt water
environment aluminum would corrode away rather quickly.


I've never had the chance to machine stainless - or any steel for that
matter. I've whittled aluminum with a mill though, and could make what
I needed. So the idea of making parts from stainless is kind of over
the top for me. I honestly don't know how hard it is to do, or how
long it would take. But if I have the choice - all other things being
equal...

Stainless isn't too bad to machine, depending on thge alloy. However, I
woudln't be surprised if the best stainless for marine use is harder to
machine. The problem with SS is that machining it work hardens it. You
want to be more agressive with it than aluminum, which might tax your
machine tools. Carbide helps a lot because it doesn't care so much that
the work is hardened.

Doug White