Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work.

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Default Metal / plastic interface cracking

Can anyone tell me how I can avoid this?

I want to design a part using the same
kind of metal - to - plastic interface as on
the Krups 203-70 coffee bean grinders but I
want to avoid the cracks in the corners.

If it gets posted it will be:
http://www.metalworking.com/dropbox/KrupsKrack.jpg
http://www.metalworking.com/dropbox/KrupsKrack.txt

Will this require say, a compliant adhesive
gasket between my metal surface and the
inside of the plastic reservoir or is this flaw
primarily caused by a different problem, say
a mixing issue that causes the plastic to be
really brittle?

Thanks!

--Winston
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Default Metal / plastic interface cracking

John R. Carroll wrote:

(...)

Those are stress cracks that result from the molding process, plasticizer
migration and shrinkage over time.


Thanks! This plastic stuff is complicated.
Clearly I will have to turn that design task
over to a specialist.

Apparently not too much time is required
for the cracks to develop.

I shot the photo about 10 minutes after taking the grinder
out of the box for the first time. I never even turned it on.

--Winston


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John R. Carroll wrote:
Winston wrote:
John R. Carroll wrote:

(...)

Those are stress cracks that result from the molding process,
plasticizer migration and shrinkage over time.


Thanks! This plastic stuff is complicated.
Clearly I will have to turn that design task
over to a specialist.

Apparently not too much time is required
for the cracks to develop.

I shot the photo about 10 minutes after taking the grinder
out of the box for the first time. I never even turned it on.


I didn't realize it was new.
Sheesh.
The part has probably cracked at the knit lines.


'Knit Lines'. That is a new one on me.
http://www.protomold.com/Design_Tips/UnitedStates/2004/2004-08_designtips/

Poor knitting has a number of causes but chief among them is improper resin
processing or low mold temperatures.
IOW, somebody screwed up either when they designed the gates/runner system
or when running the mold.


Ah Ha! So it passed final inspection while hot but
grew the cracks in the Amazon warehouse? Wow!

Thanks again.

--Winston
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Default Metal / plastic interface cracking


Can anyone tell me how I can avoid this?


When I mounted splash shields on the table of my R2E4 (cast acrylic, and
VERY prone to cracking and "spidering" from holes), I drilled the holes
in the plastic to accept a grommet. IIRC, the holes were 7/16". I don't
even want to have special bits around for plastics, so I drilled them way
undersized, and used a tapered reamer to enlarge them without cracking
the plastic.

The grommets were made for whatever hole size I drilled, and themselves
had a bore of 1/4". The 1/4"-20 screws with a washer under the head fit
just loosely in the grommets. When you squish 'em a little, the hole
swells shut, and it holds firmly to both bolt and plastic, without any
tendency for the plastic to be stressed at the union. Unless you use a
shoulder bolt, you'll have to put a bit of threadlocker in the screw
hole, since you cannot tighten the bolt too far without undoing the whole
purpose of the exercise.

LLoyd
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Default Metal / plastic interface cracking

"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote in
. 3.70:


Can anyone tell me how I can avoid this?


When I mounted splash shields on the table of my R2E4 (cast acrylic,
and VERY prone to cracking and "spidering" from holes), I drilled the
holes in the plastic to accept a grommet. IIRC, the holes were 7/16".
I don't even want to have special bits around for plastics, so I
drilled them way undersized, and used a tapered reamer to enlarge them
without cracking the plastic.

The grommets were made for whatever hole size I drilled, and
themselves had a bore of 1/4". The 1/4"-20 screws with a washer under
the head fit just loosely in the grommets. When you squish 'em a
little, the hole swells shut, and it holds firmly to both bolt and
plastic, without any tendency for the plastic to be stressed at the
union. Unless you use a shoulder bolt, you'll have to put a bit of
threadlocker in the screw hole, since you cannot tighten the bolt too
far without undoing the whole purpose of the exercise.


Just make sure you keep the threadlocker AWAY from the plastic. I'm not
sure about acrylic, but I know from sad experience what happens to Lexan
when you get Loctite on it. We had a rush job that was just about
finished when an overzealous technician decided to applied threadlocker
to some 3/8" Lexan parts it took several days to machine. They swelled
up & cracked like mad. Had to start all over again, with even less time.

Doug White


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Default Metal / plastic interface cracking

Lloyd E. Sponenburgh wrote:
Can anyone tell me how I can avoid this?


When I mounted splash shields on the table of my R2E4 (cast acrylic, and
VERY prone to cracking and "spidering" from holes), I drilled the holes
in the plastic to accept a grommet. IIRC, the holes were 7/16". I don't
even want to have special bits around for plastics, so I drilled them way
undersized, and used a tapered reamer to enlarge them without cracking
the plastic.

The grommets were made for whatever hole size I drilled, and themselves
had a bore of 1/4". The 1/4"-20 screws with a washer under the head fit
just loosely in the grommets. When you squish 'em a little, the hole
swells shut, and it holds firmly to both bolt and plastic, without any
tendency for the plastic to be stressed at the union. Unless you use a
shoulder bolt, you'll have to put a bit of threadlocker in the screw
hole, since you cannot tighten the bolt too far without undoing the whole
purpose of the exercise.


So my intuition about an elastomer gasket
wasn't too far off then, aye?

Excellent! Thanks Lloyd.

--Winston
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Default Metal / plastic interface cracking

Doug White wrote:
"Lloyd E. Sponenburgh"lloydspinsidemindspring.com wrote in
. 3.70:


Can anyone tell me how I can avoid this?


When I mounted splash shields on the table of my R2E4 (cast acrylic,
and VERY prone to cracking and "spidering" from holes), I drilled the
holes in the plastic to accept a grommet. IIRC, the holes were 7/16".
I don't even want to have special bits around for plastics, so I
drilled them way undersized, and used a tapered reamer to enlarge them
without cracking the plastic.

The grommets were made for whatever hole size I drilled, and
themselves had a bore of 1/4". The 1/4"-20 screws with a washer under
the head fit just loosely in the grommets. When you squish 'em a
little, the hole swells shut, and it holds firmly to both bolt and
plastic, without any tendency for the plastic to be stressed at the
union. Unless you use a shoulder bolt, you'll have to put a bit of
threadlocker in the screw hole, since you cannot tighten the bolt too
far without undoing the whole purpose of the exercise.


Just make sure you keep the threadlocker AWAY from the plastic. I'm not
sure about acrylic, but I know from sad experience what happens to Lexan
when you get Loctite on it. We had a rush job that was just about
finished when an overzealous technician decided to applied threadlocker
to some 3/8" Lexan parts it took several days to machine. They swelled
up& cracked like mad. Had to start all over again, with even less time.

Doug White


Reminds me of a misadventure I had with acrylic and an acetone
spill once.

Thanks for the reminder.

--Winston
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Default Metal / plastic interface cracking

On Dec 25, 10:06*am, Winston wrote:
Can anyone tell me how I can avoid this?

I want to design a part using the same
kind of metal - to - plastic interface as on
the Krups 203-70 coffee bean grinders but I
want to avoid the cracks in the corners.

If it gets posted it will be:http://www.metalworking.com/dropbox/...KrupsKrack.txt

Will this require say, a compliant adhesive
gasket between my metal surface and the
inside of the plastic reservoir or is this flaw
primarily caused by a different problem, say
a mixing issue that causes the plastic to be
really brittle?

Thanks!

--Winston


It could be a material problem or maybe the part that broke was
designed to use the minimum amount of plastic necessary in order to
cut manufacturing costs. You could try your hand at plastic welding,
maybe with a small soldering iron and proper tip. Another possibility
might be solvent welding if it’s made of PVC. I’ll bet that the part
wouldn’t have broken if the sections were thick enough.
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Denis G. wrote:
On Dec 25, 10:06 am, wrote:
Can anyone tell me how I can avoid this?

I want to design a part using the same
kind of metal - to - plastic interface as on
the Krups 203-70 coffee bean grinders but I
want to avoid the cracks in the corners.

If it gets posted it will be:


http://www.metalworking.com/dropbox/KrupsKrack.jpg

http://www.metalworking.com/dropbox/KrupsKrack.txt

(....)

It could be a material problem or maybe the part that broke was
designed to use the minimum amount of plastic necessary in order to
cut manufacturing costs. You could try your hand at plastic welding,
maybe with a small soldering iron and proper tip.
Another possibility
might be solvent welding if it’s made of PVC.


I'm not going to repair the existing grinder, especially since
I need a different type anyway. (Who knew?)

I’ll bet that the part
wouldn’t have broken if the sections were thick enough.


My application will use softer plastic, so perhaps
cracking won't be an issue.

--Winston






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Default Metal / plastic interface cracking

Winston fired this volley in
:

So my intuition about an elastomer gasket
wasn't too far off then, aye?

Excellent! Thanks Lloyd.


Winston, you have mentioned the "other alternative".

Instead of holes, grommets, and bolts, some applications have a channel
frame all-round the work with a u-channel-shaped gasket capturing the
edge of the plastic sheet.

The only problem with this method for the 'ordinary' shop guy is getting
gasket and frame material that will match up with one-another and the
thickness of the plastic.

LLoyd
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On Dec 26, 12:04*am, Winston wrote:
Denis G. wrote:
On Dec 25, 10:06 am, *wrote:
Can anyone tell me how I can avoid this?


I want to design a part using the same
kind of metal - to - plastic interface as on
the Krups 203-70 coffee bean grinders but I
want to avoid the cracks in the corners.


If it gets posted it will be:


http://www.metalworking.com/dropbox/KrupsKrack.jpg

http://www.metalworking.com/dropbox/KrupsKrack.txt

(....)

It could be a material problem or maybe the part that broke was
designed to use the minimum amount of plastic necessary in order to
cut manufacturing costs. *You could try your hand at plastic welding,
maybe with a small soldering iron and proper tip.
Another possibility
might be solvent welding if it’s made of PVC.


I'm not going to repair the existing grinder, especially since
I need a different type anyway. (Who knew?)

I’ll bet that the part
wouldn’t have broken if the sections were thick enough.


My application will use softer plastic, so perhaps
cracking won't be an issue.

--Winston


The only issue with a softer plastic might be a greater likihood of
staining, but maybe it won't matter for your application.
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Denis G. wrote:
On Dec 26, 12:04 am, wrote:


(...)

My application will use softer plastic, so perhaps
cracking won't be an issue.

--Winston


The only issue with a softer plastic might be a greater likihood of
staining, but maybe it won't matter for your application.


You are right.
This will be a 'liner' of a larger insulated container
that will very rarely see the light of day.

--Winston

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Lloyd E. Sponenburgh wrote:
fired this volley in
:

So my intuition about an elastomer gasket
wasn't too far off then, aye?

Excellent! Thanks Lloyd.


Winston, you have mentioned the "other alternative".

Instead of holes, grommets, and bolts, some applications have a channel
frame all-round the work with a u-channel-shaped gasket capturing the
edge of the plastic sheet.

The only problem with this method for the 'ordinary' shop guy is getting
gasket and frame material that will match up with one-another and the
thickness of the plastic.


I had a very similar challenge sealing the end of a
30 gallon HDPE drum to the inside of a cylindrical plastic
flange. The application did not require a lot of strength.

After I cleaned and degreased both pieces, I assembled
them and flipped them 'opening down'. I poured some
castable elastomer into the gap between the inside
of the flange and the outside of the drum.

It worked a treat!

The elastomer was just 'runny' enough to find and seal
the gap between the two cylinders, without leaking out
of the gap. It was this stuff IIRC:
http://www.devcon.com/products/produ...amily=Flexane®
80 Liquid

I expect that one could pour this stuff into a machined
mold to create a gasket of just about any shape, too.


--Winston



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Default Metal / plastic interface cracking

Snag wrote:
Winston wrote:


(...)

Can you recommend a better unit?

--Winston


I like my B&D model CBM210 . I'm the only coffee drinker in my house . An
8 second grind makes just the right amount of coffee for my little 5 cup
coffeemaker . I'm set like 4 or 5 clicks from the finest grind .
And it's around 30 bucks at Walmart .


Thanks, Snag!

--Winston
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Default Metal / plastic interface cracking

In article ,
Winston wrote:

Steve Ackman wrote:
, on Sat, 25 Dec 2010 08:06:59 -0800,
Winston, wrote:

Can anyone tell me how I can avoid this?


Use a coffee grinder instead of a coffee basher?
;-)


Help, Sir Coffee!

Is this one all right?
http://www.bodumusa.com/shop/line.as...SLT=&mscssid=T
399V5FNF5FH8H0KXMCTXNK6UPGJE3F4

Can you recommend a better unit?


According to a Consumer Reports article some years ago, burr grinders
work very well, especially for making a fine grind for expresso, but
need a lot of cleaning to keep rancid coffee oil flavors.

We use a Krups Fast Touch Coffee Grinder, which is oval and of the
impact type, and have not had problems with cracking. I recall that the
broken grinder was not oval, and the cracks formed at the corners.

http://www.krupsonlinestore.com/prod...203-42&MENU=gr
inders&SELECT=&SKW=krugrind

They retail for $13 to $18, so one does not repair them. Not that it's
been needed, and the current one is at least ten years old.

Joe Gwinn
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Joseph Gwinn wrote:
In ,
wrote:

Steve Ackman wrote:
, on Sat, 25 Dec 2010 08:06:59 -0800,
Winston, wrote:

Can anyone tell me how I can avoid this?

Use a coffee grinder instead of a coffee basher?
;-)


Help, Sir Coffee!

Is this one all right?
http://www.bodumusa.com/shop/line.as...SLT=&mscssid=T
399V5FNF5FH8H0KXMCTXNK6UPGJE3F4

Can you recommend a better unit?


According to a Consumer Reports article some years ago, burr grinders
work very well, especially for making a fine grind for expresso, but
need a lot of cleaning to keep rancid coffee oil flavors.

We use a Krups Fast Touch Coffee Grinder, which is oval and of the
impact type, and have not had problems with cracking. I recall that the
broken grinder was not oval, and the cracks formed at the corners.


It's a trick of perspective. I shot the picture along the
long axis of the oval.

http://www.krupsonlinestore.com/prod...203-42&MENU=gr
inders&SELECT=&SKW=krugrind

They retail for $13 to $18, so one does not repair them. Not that it's
been needed, and the current one is at least ten years old.


Yup. Our old one lasted many years.
It's become sluggish, prompting the replacement.

For now, we are back using the old one and the new one is
in the garbage can.

--Winston
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In article ,
Winston wrote:

Joseph Gwinn wrote:
In ,
wrote:

Steve Ackman wrote:
, on Sat, 25 Dec 2010 08:06:59 -0800,
Winston, wrote:

Can anyone tell me how I can avoid this?

Use a coffee grinder instead of a coffee basher?
;-)

Help, Sir Coffee!

Is this one all right?
http://www.bodumusa.com/shop/line.as...K=&SLT=&mscssi
d=T
399V5FNF5FH8H0KXMCTXNK6UPGJE3F4

Can you recommend a better unit?


According to a Consumer Reports article some years ago, burr grinders
work very well, especially for making a fine grind for expresso, but
need a lot of cleaning to keep rancid coffee oil flavors.

We use a Krups Fast Touch Coffee Grinder, which is oval and of the
impact type, and have not had problems with cracking. I recall that the
broken grinder was not oval, and the cracks formed at the corners.


It's a trick of perspective. I shot the picture along the
long axis of the oval.

http://www.krupsonlinestore.com/prod...203-42&MENU=gr
inders&SELECT=&SKW=krugrind

They retail for $13 to $18, so one does not repair them. Not that it's
been needed, and the current one is at least ten years old.


Yup. Our old one lasted many years.
It's become sluggish, prompting the replacement.

For now, we are back using the old one and the new one is
in the garbage can.


Maybe it *is* worth fixing the old one, if the new ones are built
pre-busted.

I bet the sluggishness is due to dirty bearings or the like. Or
congealed coffee oils. A disassembly, cleaning, and oiling may be the
charm.

But I would return the busted new one, just to be a pill.

Joe Gwinn.
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Joseph Gwinn wrote:
In ,
wrote:


(...)

For now, we are back using the old one and the new one is
in the garbage can.


Maybe it *is* worth fixing the old one, if the new ones are built
pre-busted.


For now we have a replacement from one of Krups' competitors
so that we can make Java until I decide which conical burr
grinder is the one for us.

I bet the sluggishness is due to dirty bearings or the like. Or
congealed coffee oils. A disassembly, cleaning, and oiling may be the
charm.


I looked into that. The enclosure snaps together semi-permanently
and requires a complicated jig to apply just the right pressure
to many key points to spring all the necessary latches for
disassembly.

But I would return the busted new one, just to be a pill.


I suggested that. SWMBO reminded me that Amazon was not interested
in our petty concerns, though. Oh Well.

--Winston


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In article ,
Winston wrote:

Joseph Gwinn wrote:
In ,
wrote:


(...)

For now, we are back using the old one and the new one is
in the garbage can.


Maybe it *is* worth fixing the old one, if the new ones are built
pre-busted.


For now we have a replacement from one of Krups' competitors
so that we can make Java until I decide which conical burr
grinder is the one for us.

I bet the sluggishness is due to dirty bearings or the like. Or
congealed coffee oils. A disassembly, cleaning, and oiling may be the
charm.


I looked into that. The enclosure snaps together semi-permanently
and requires a complicated jig to apply just the right pressure
to many key points to spring all the necessary latches for
disassembly.


I bet not. I open such things all the time, by a method akin to picking
a lock. With manufacturing tolerance, one of the latches will tighten
first. Open it with a probe, and the cover will move open slightly,
enough so the latch won't re-latch. Another latch will now be first,
etc. Use a taper or two to hold things apart between steps, driving the
tapers deeper whenever they become loose.


But I would return the busted new one, just to be a pill.


I suggested that. SWMBO reminded me that Amazon was not interested
in our petty concerns, though. Oh Well.


SWMBO is likely correct about Amazon. I would return it to the
manufacturer, who is supposed to care.


Joe Gwinn
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Joseph Gwinn wrote:

(...)

I bet not. I open such things all the time, by a method akin to picking
a lock. With manufacturing tolerance, one of the latches will tighten
first. Open it with a probe, and the cover will move open slightly,
enough so the latch won't re-latch. Another latch will now be first,
etc. Use a taper or two to hold things apart between steps, driving the
tapers deeper whenever they become loose.


I open latching electronic enclosures using that method as
well. The remote control to my TV is a prime example.
It works great because the plastic is pliable and rather
thin.

On The Other Hand....

The Krups grinder is made from thickish, brittle plastic that does
not allow the incremental approach that we both find useful
for electronic housings.

I did some exploratory work but gave it up as a bad job.

But I would return the busted new one, just to be a pill.


I suggested that. SWMBO reminded me that Amazon was not interested
in our petty concerns, though. Oh Well.


SWMBO is likely correct about Amazon. I would return it to the
manufacturer, who is supposed to care.


The folks at Krups made all the right noises.
Today they sent a nice eMail asking me to send them
the defective unit with the purchase receipt.

I have no doubt that they would replace it under
warranty but I'm not going to spend $10 and an
afternoon to get it properly boxed and returned
just so I can get another of the same kind of
unit.

We now have *two* backup coffee grinders so I think
I will focus my time on more profitable stuff.

Joe, I'd be happy to send the new one to you for
your entertainment. It strikes me that one could
very easily stab ones self with a screwdriver
trying to hack into it. So Beware!

Just email me offline using the
address on the bottom of my website
and it is yours.

http://mysite.verizon.net/reswoead/

--Winston
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Default Metal / plastic interface cracking

In article ,
Winston wrote:

Joseph Gwinn wrote:

(...)

I bet not. I open such things all the time, by a method akin to picking
a lock. With manufacturing tolerance, one of the latches will tighten
first. Open it with a probe, and the cover will move open slightly,
enough so the latch won't re-latch. Another latch will now be first,
etc. Use a taper or two to hold things apart between steps, driving the
tapers deeper whenever they become loose.


I open latching electronic enclosures using that method as
well. The remote control to my TV is a prime example.
It works great because the plastic is pliable and rather
thin.

On The Other Hand....

The Krups grinder is made from thickish, brittle plastic that does
not allow the incremental approach that we both find useful
for electronic housings.

I did some exploratory work but gave it up as a bad job.


If it's really that brittle, how did they get it together without making
too much scrap?


But I would return the busted new one, just to be a pill.

I suggested that. SWMBO reminded me that Amazon was not interested
in our petty concerns, though. Oh Well.


SWMBO is likely correct about Amazon. I would return it to the
manufacturer, who is supposed to care.


The folks at Krups made all the right noises.
Today they sent a nice eMail asking me to send them
the defective unit with the purchase receipt.

I have no doubt that they would replace it under
warranty but I'm not going to spend $10 and an
afternoon to get it properly boxed and returned
just so I can get another of the same kind of
unit.


The point is to cost Krups something, "just to be a pill." It's their
error signal. Maybe they will even do a post mortem on the returned
unit.


We now have *two* backup coffee grinders so I think
I will focus my time on more profitable stuff.

Joe, I'd be happy to send the new one to you for
your entertainment. It strikes me that one could
very easily stab ones self with a screwdriver
trying to hack into it. So Beware!

Just email me offline using the
address on the bottom of my website
and it is yours.

http://mysite.verizon.net/reswoead/


Thanks for the offer, but doesn't this cost the same as sending it back
to Krups?

I just looked at the perfectly functional Krups Model 203 that my wife
bought a very long time ago. It is held together with screws. Maybe
the better solution is to haunt Goodwill stores.


Joe Gwinn


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Joseph Gwinn wrote:
In ,
wrote:


(...)

I did some exploratory work but gave it up as a bad job.


If it's really that brittle, how did they get it together without making
too much scrap?


That is why I think you would like to have a look at it
in person. Any number of RCM denizens, present company
included, could easily design plastic latch features
which would engage but would not disengage without
special tooling or part breakage.

The Krups blade bean basher appears to be just such a
design. One example is worth ten thousand words.

(...)

I have no doubt that they would replace it under
warranty but I'm not going to spend $10 and an
afternoon to get it properly boxed and returned
just so I can get another of the same kind of
unit.


The point is to cost Krups something, "just to be a pill." It's their
error signal. Maybe they will even do a post mortem on the returned
unit.


If error signals really worked, GM wouldn't have
been a government subsidiary for the last five months
and they wouldn't have handed over their marketplace
nearly as readily as they did.

Krups has the photo and the screaming and knashing
of teeth from hundreds of other customers. One more
unit is not going to change any minds.

We now have *two* backup coffee grinders so I think
I will focus my time on more profitable stuff.

Joe, I'd be happy to send the new one to you for
your entertainment. It strikes me that one could
very easily stab ones self with a screwdriver
trying to hack into it. So Beware!

Just email me offline using the
address on the bottom of my website
and it is yours.

http://mysite.verizon.net/reswoead/


Thanks for the offer, but doesn't this cost the same as sending it back
to Krups?


It would. I figure you would enjoy telling me how
you disassembled it in 40 seconds using only a
nail file, recast the housing using the 'lost wax'
process and reassembled it with machine screws
before lunchtime.

That would be *worth* the price of admission.

I just looked at the perfectly functional Krups Model 203 that my wife
bought a very long time ago. It is held together with screws. Maybe
the better solution is to haunt Goodwill stores.


As soon as my two 'backup' grinders konk out, I will
look in earnest for a cone burr grinder as Mssr. Ackman
has suggested. Give it another year or so.

--Winston
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Default Metal / plastic interface cracking

In article ,
Winston wrote:

Joseph Gwinn wrote:
In ,
wrote:


(...)

I did some exploratory work but gave it up as a bad job.


If it's really that brittle, how did they get it together without making
too much scrap?


That is why I think you would like to have a look at it
in person. Any number of RCM denizens, present company
included, could easily design plastic latch features
which would engage but would not disengage without
special tooling or part breakage.

The Krups blade bean basher appears to be just such a
design. One example is worth ten thousand words.

(...)

I have no doubt that they would replace it under
warranty but I'm not going to spend $10 and an
afternoon to get it properly boxed and returned
just so I can get another of the same kind of
unit.


The point is to cost Krups something, "just to be a pill." It's their
error signal. Maybe they will even do a post mortem on the returned
unit.


If error signals really worked, GM wouldn't have
been a government subsidiary for the last five months
and they wouldn't have handed over their marketplace
nearly as readily as they did.

Krups has the photo and the screaming and knashing
of teeth from hundreds of other customers. One more
unit is not going to change any minds.


O ye of little faith...


We now have *two* backup coffee grinders so I think
I will focus my time on more profitable stuff.

Joe, I'd be happy to send the new one to you for
your entertainment. It strikes me that one could
very easily stab ones self with a screwdriver
trying to hack into it. So Beware!

Just email me offline using the
address on the bottom of my website
and it is yours.

http://mysite.verizon.net/reswoead/


Thanks for the offer, but doesn't this cost the same as sending it back
to Krups?


It would. I figure you would enjoy telling me how
you disassembled it in 40 seconds using only a
nail file, recast the housing using the 'lost wax'
process and reassembled it with machine screws
before lunchtime.

That would be *worth* the price of admission.


The boasting privilege is tempting, especially if fiction is allowed...


I just looked at the perfectly functional Krups Model 203 that my wife
bought a very long time ago. It is held together with screws. Maybe
the better solution is to haunt Goodwill stores.


As soon as my two 'backup' grinders konk out, I will
look in earnest for a cone burr grinder as Mssr. Ackman
has suggested. Give it another year or so.


I have a modest suggestion. There is a dead simple fully mechanical
approach with only one slow-moving part, the mortar and pestle. I bet a
granite model would work well, and last forever.

Joe Gwinn
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Default Metal / plastic interface cracking

Joseph Gwinn wrote:
In ,
wrote:


(...)

Krups has the photo and the screaming and knashing
of teeth from hundreds of other customers. One more
unit is not going to change any minds.


O ye of little faith...


A most precise and accurate description.


(...)

It would. I figure you would enjoy telling me how
you disassembled it in 40 seconds using only a
nail file, recast the housing using the 'lost wax'
process and reassembled it with machine screws
before lunchtime.

That would be *worth* the price of admission.


The boasting privilege is tempting, especially if fiction is allowed...


USENET: Where the truth is tolerated.

(Psst. Larry! Teeshirt!)

(...)

I have a modest suggestion. There is a dead simple fully mechanical
approach with only one slow-moving part, the mortar and pestle. I bet a
granite model would work well, and last forever.


That is a most elegant and quiet approach.

But it could be improved upon with a 5 axis controller
and a couple hundred man-hours of design time...



--Winston
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Default Metal / plastic interface cracking

On Tue, 28 Dec 2010 15:01:21 -0800, Winston
wrote:

Joseph Gwinn wrote:
In ,
wrote:


(...)

Krups has the photo and the screaming and knashing
of teeth from hundreds of other customers. One more
unit is not going to change any minds.


O ye of little faith...


A most precise and accurate description.


(...)

It would. I figure you would enjoy telling me how
you disassembled it in 40 seconds using only a
nail file, recast the housing using the 'lost wax'
process and reassembled it with machine screws
before lunchtime.

That would be *worth* the price of admission.


The boasting privilege is tempting, especially if fiction is allowed...


USENET: Where the truth is tolerated.


I like it!


(Psst. Larry! Teeshirt!)


Buy the rest of my "Clinton Never Exhaled" and/or "The Hindenberg, The
Titanic, The Clintons" tees and I'll get right on it. I need capital
for that process, son.


(...)

I have a modest suggestion. There is a dead simple fully mechanical
approach with only one slow-moving part, the mortar and pestle. I bet a
granite model would work well, and last forever.


That is a most elegant and quiet approach.


"Gee, your coffee has the most subtle, Earthy, stony taste to it,
Joe."

--
Make the best use of what is in your power,
and take the rest as it happens.
-- Epictetus


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Default Metal / plastic interface cracking

In article ,
Winston wrote:

Joseph Gwinn wrote:
In ,
wrote:


(...)

Krups has the photo and the screaming and knashing
of teeth from hundreds of other customers. One more
unit is not going to change any minds.


O ye of little faith...


A most precise and accurate description.


(...)

It would. I figure you would enjoy telling me how
you disassembled it in 40 seconds using only a
nail file, recast the housing using the 'lost wax'
process and reassembled it with machine screws
before lunchtime.

That would be *worth* the price of admission.


The boasting privilege is tempting, especially if fiction is allowed...


USENET: Where the truth is tolerated.

(Psst. Larry! Teeshirt!)


I'm unclear on one thing. Will this help or hurt our reputation?


(...)

I have a modest suggestion. There is a dead simple fully mechanical
approach with only one slow-moving part, the mortar and pestle. I bet a
granite model would work well, and last forever.


That is a most elegant and quiet approach.

But it could be improved upon with a 5 axis controller
and a couple hundred man-hours of design time...


Wouldn't a one-axis approach suffice? Up and down goes the pestle. Use
a traditional drop-hammer mechanism, powered by steam. There - we got
some iron into the story. And steampunk.

Joe Gwinn
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Default Metal / plastic interface cracking

Larry Jaques fired this volley in
:

"Gee, your coffee has the most subtle, Earthy, stony taste to it,
Joe."


You could use it to grind peppers, too, and call the coffee, "Los
Molcajetes Cafe Cayenne".

LLoyd
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Default Metal / plastic interface cracking

Joseph Gwinn wrote:
In ,
wrote:

Joseph Gwinn wrote:


(...)

USENET: Where the truth is tolerated.

(Psst. Larry! Teeshirt!)


I'm unclear on one thing. Will this help or hurt our reputation?


With whom? -- Important Question

I have a modest suggestion. There is a dead simple fully mechanical
approach with only one slow-moving part, the mortar and pestle. I bet a
granite model would work well, and last forever.


That is a most elegant and quiet approach.

But it could be improved upon with a 5 axis controller
and a couple hundred man-hours of design time...


Wouldn't a one-axis approach suffice? Up and down goes the pestle. Use
a traditional drop-hammer mechanism, powered by steam. There - we got
some iron into the story. And steampunk.


Joe, you are a genius!

--Winston
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Default Metal / plastic interface cracking

Steve Ackman wrote:
, on Mon, 27 Dec 2010 21:24:16 -0800,
Winston, wrote:


(...)

Make mine a doppio.


I guess I should have said _GOOD_ espresso... as in
the all too rarely attainable "God Shot." ;-)


Transcendental Cuppa?

I'd buy that.

--Winston

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Default Metal / plastic interface cracking


Winston wrote:

Joseph Gwinn wrote:
In ,
wrote:


(...)

Krups has the photo and the screaming and knashing
of teeth from hundreds of other customers. One more
unit is not going to change any minds.


O ye of little faith...


A most precise and accurate description.


(...)

It would. I figure you would enjoy telling me how
you disassembled it in 40 seconds using only a
nail file, recast the housing using the 'lost wax'
process and reassembled it with machine screws
before lunchtime.

That would be *worth* the price of admission.


The boasting privilege is tempting, especially if fiction is allowed...


USENET: Where the truth is tolerated.

(Psst. Larry! Teeshirt!)

(...)

I have a modest suggestion. There is a dead simple fully mechanical
approach with only one slow-moving part, the mortar and pestle. I bet a
granite model would work well, and last forever.


That is a most elegant and quiet approach.

But it could be improved upon with a 5 axis controller
and a couple hundred man-hours of design time...



Just use a 20 ton press. ;-)


--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.
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