Hi all,

I've got a 180 A stick welding set, but it's AC only. I may want to weld
stainless in the future, but am unlikely to want to weld aluminium.
(Okay, I'm thinking of building a coffee roaster when I've finished the
phase convertor project, and it would be attractive to build it from
stainless). I've heard that you need DC TIG to weld stainless, is that
right? I know where I might get an add-on TIG unit for my welder, but
the guy said it was suitable for aluminium only.

So here are the questions. If I want to TIG weld stainless, must it be
DC TIG? If so, is it possible to get a small add-on unit which will
rectify the current from an AC stick welder and enable it to be used for
DC TIG? I don't have a picture of my welder, but it's pretty similar to
this one I saw on eBay recently:

http://cgi.ebay.co.uk/ws/eBayISAPI.d...tem=7559244604

Mine is a little larger and has an in-built battery charger, and it's
built by Cytringan rather than Oxford, but the current rating is the
same. Whoever scored that set on eBay got a nice deal. I'm not eager to
replace the set as it suits my stick welding needs and offers 100% duty
cycle, plus I like it a lot. Is there any way to weld stainless without
getting a second welder?

Suggestions would be appreciated.

Chris

On Sat, 12 Nov 2005 00:24:37 +0000 (UTC), Christopher Tidy
wrote:

Hi all,

I've got a 180 A stick welding set, but it's AC only. I may want to weld
stainless in the future, but am unlikely to want to weld aluminium.
(Okay, I'm thinking of building a coffee roaster when I've finished the
phase convertor project, and it would be attractive to build it from
stainless). I've heard that you need DC TIG to weld stainless, is that
right? I know where I might get an add-on TIG unit for my welder, but
the guy said it was suitable for aluminium only.

So here are the questions. If I want to TIG weld stainless, must it be
DC TIG? If so, is it possible to get a small add-on unit which will
rectify the current from an AC stick welder and enable it to be used for
DC TIG? I don't have a picture of my welder, but it's pretty similar to
this one I saw on eBay recently:

http://cgi.ebay.co.uk/ws/eBayISAPI.d...tem=7559244604

Mine is a little larger and has an in-built battery charger, and it's
built by Cytringan rather than Oxford, but the current rating is the
same. Whoever scored that set on eBay got a nice deal. I'm not eager to
replace the set as it suits my stick welding needs and offers 100% duty
cycle, plus I like it a lot. Is there any way to weld stainless without
getting a second welder?

Suggestions would be appreciated.

Chris
Chris,
I don't think you can tig weld stainless with AC. I tried by accident
before and it weren't pretty. However, you may be able to stick weld
it with AC. Call the weld supply and see if they have rod that would
do this.
ERS

I would expect you can AC tig weld stainless. I can't think of any
reason that you couldn't. But I know you can stick weld stainless with
an AC welder. May not be as pretty as TIG.

You can also silver solder ( braze ) stainless. It might be the best
looking way to do it.
Is the stainless fairly thin? Can you use a brake to put a flange on
the edge and have a lap joint? You could use either propane or carbon
arc.

Dan
C Is there any way to weld stainless without
getting a second welder?

Suggestions would be appreciated.

Chris

wrote:
I would expect you can AC tig weld stainless. I can't think of any
reason that you couldn't. But I know you can stick weld stainless with
an AC welder. May not be as pretty as TIG.

You can also silver solder ( braze ) stainless. It might be the best
looking way to do it.
Is the stainless fairly thin? Can you use a brake to put a flange on
the edge and have a lap joint? You could use either propane or carbon
arc.

Dan and Eric: Thanks for suggesting that I could stick weld stainless.
I'll do a search online and look for suitable electrodes, then get in
touch with the welding supply store (if my coffee roaster project gets
off the ground).

Dan: It would be thin-ish stainless, but would likely have to be 1.6 to
2 mm if I was going to stick weld it. I don't have a brake, so putting a
flange on the stainless could be a problem. But I do recall than the
data plate on my welder says something about using a carbon arc torch on
the 80 V AC terminal. I'll have a look.

Thanks for the suggestions.

Chris

Most of the time I use a wood stud with C-clamps to clamp sheet metal
to a steel channel. Then use a mallet to form a 90 degree bend. More
work than a brake and not as nice looking but it works. Just start at
one end and tap it over about 20 degrees and go down the line. Then
come back bending it another 20 degrees or so. untill you can flatten
it against the channel for a 90 degree bend. Works okay for 1 mm
stainless.


Dan

Yes, you can put rectifiers on a stick welder to make it DC for either stick
or TIG. I've done it. The usual problem is that with a bridge rectifier,
neither stinger (or torch) nor groundclamp are really "ground" so the work
can't be grounded. That really isn't a problem other than you need to know
about it. You won't have HF start -- and shouldn't need it to TIG SS.

Another big difference is that you won't have footpedal control -- but that
may not be a big deal with SS. My DialArc 250 was originally used for
welding SS silos together; came with about 50 feet of leather-enclosed
cables and waterline -- and no footpedal! There was a switch on the torch
handle, but it was just an on-off switch. So apparantly the guys that were
doing that thin SS had no problem doing it without a footpedal.



"Christopher Tidy" wrote in message
...
Hi all,

I've got a 180 A stick welding set, but it's AC only. I may want to weld
stainless in the future, but am unlikely to want to weld aluminium. (Okay,
I'm thinking of building a coffee roaster when I've finished the phase
convertor project, and it would be attractive to build it from stainless).
I've heard that you need DC TIG to weld stainless, is that right? I know
where I might get an add-on TIG unit for my welder, but the guy said it
was suitable for aluminium only.

So here are the questions. If I want to TIG weld stainless, must it be DC
TIG? If so, is it possible to get a small add-on unit which will rectify
the current from an AC stick welder and enable it to be used for DC TIG? I
don't have a picture of my welder, but it's pretty similar to this one I
saw on eBay recently:

http://cgi.ebay.co.uk/ws/eBayISAPI.d...tem=7559244604

Mine is a little larger and has an in-built battery charger, and it's
built by Cytringan rather than Oxford, but the current rating is the same.
Whoever scored that set on eBay got a nice deal. I'm not eager to replace
the set as it suits my stick welding needs and offers 100% duty cycle,
plus I like it a lot. Is there any way to weld stainless without getting a
second welder?

Suggestions would be appreciated.

Chris

You can get add on rectifier/ smoother boxes as well as add on HF unit.
For some years I used this set-up with a Max-arc rectifier and Max-arc
HF unit connected to a Pickhill (like Oxford) 180A oil cooled welder. It
worked well but no current control for ramping. Both units were
purchased in the UK 2nd hand. I think Max-arc themselves are long gone.
The rectifier also contained a choke to smooth the DC.

Christopher Tidy wrote:

Hi all,

I've got a 180 A stick welding set, but it's AC only. I may want to
weld stainless in the future, but am unlikely to want to weld
aluminium. (Okay, I'm thinking of building a coffee roaster when I've
finished the phase convertor project, and it would be attractive to
build it from stainless). I've heard that you need DC TIG to weld
stainless, is that right? I know where I might get an add-on TIG unit
for my welder, but the guy said it was suitable for aluminium only.

So here are the questions. If I want to TIG weld stainless, must it be
DC TIG? If so, is it possible to get a small add-on unit which will
rectify the current from an AC stick welder and enable it to be used
for DC TIG? I don't have a picture of my welder, but it's pretty
similar to this one I saw on eBay recently:

http://cgi.ebay.co.uk/ws/eBayISAPI.d...tem=7559244604

Mine is a little larger and has an in-built battery charger, and it's
built by Cytringan rather than Oxford, but the current rating is the
same. Whoever scored that set on eBay got a nice deal. I'm not eager
to replace the set as it suits my stick welding needs and offers 100%
duty cycle, plus I like it a lot. Is there any way to weld stainless
without getting a second welder?

Suggestions would be appreciated.

Chris

David Billington wrote:
You can get add on rectifier/ smoother boxes as well as add on HF unit.
For some years I used this set-up with a Max-arc rectifier and Max-arc
HF unit connected to a Pickhill (like Oxford) 180A oil cooled welder. It
worked well but no current control for ramping. Both units were
purchased in the UK 2nd hand. I think Max-arc themselves are long gone.
The rectifier also contained a choke to smooth the DC.

Thanks for advice. I'll keep an eye out for a used rectifier unit. Any
idea what they're worth in decent condition?

Best wishes,

Chris

Don Foreman wrote:

Yes, you can put rectifiers on a stick welder to make it DC for either stick
or TIG. I've done it. The usual problem is that with a bridge rectifier,
neither stinger (or torch) nor groundclamp are really "ground" so the work
can't be grounded. ...

Why can't the work be grounded? Neither side of the welder secondary is
grounded and the whole secondary circuit is floating. How could there
be any circuit to ground? I'm sure that I'm missing something - what is it?

Bob

Ignoramus408 wrote:
On Sun, 13 Nov 2005 01:25:46 +0000 (UTC), Christopher Tidy wrote:

David Billington wrote:

You can get add on rectifier/ smoother boxes as well as add on HF unit.
For some years I used this set-up with a Max-arc rectifier and Max-arc
HF unit connected to a Pickhill (like Oxford) 180A oil cooled welder. It
worked well but no current control for ramping. Both units were
purchased in the UK 2nd hand. I think Max-arc themselves are long gone.
The rectifier also contained a choke to smooth the DC.

Thanks for advice. I'll keep an eye out for a used rectifier unit. Any
idea what they're worth in decent condition?


You can make your own rectifier from diodes, or buy a fully made
rectifier bridge. They sell a lot of them on ebay.

Lot of 4 Diode 1N3267 - 400 Volt 160 Amp

http://cgi.ebay.com/Lot-of-4-Diode-1...cmdZ ViewItem

You can make a rectifier bridge out of SCRs, as well:


SCR Stud Mounted 300 Amp Heavy Duty 250051 High Volt

http://cgi.ebay.com/SCR-Stud-Mounted...cm dZViewItem

these SCRs could get you weld at under 180A.
http://cgi.ebay.com/6-Eupec-SCR-Rect...c mdZViewItem

2 Huge SCRs, SCR diode
http://cgi.ebay.com/2-Huge-SCRs-SCR-...c mdZViewItem


I have two more SCRs that I can give you, good for 300A each, free
except you pay shipping to UK.

http://igor.chudov.com/tmp/TT170N-SCR.pdf

Note that besides a rectifier, it would be good to have something to
smooth your DC voltage. That usually includes some capacitors. I can
give you three 19,000 uF 75V capacitors that are already paralleled
and have discharge resistors on them already, for free, if you pay
shipping to UK.

If you look for SCR on ebay, also type thyristor in the search box.

http://cgi.ebay.com/10-IR-620-Amp-SC...QQcmdZViewItem


i

Thanks for all the kind offers! I'll think about building an add-on and
get back to you if I do, but I was hoping I might find a ready built
unit this time. Otherwise every tool becomes a project, as I'm sure
you've discovered :-). That said, postage from the US to the UK is
usually much cheaper than the other way around. USPS seem to do work as
opposed to sitting behind their desks in trendy hi-vis vests chewing gum
and listening to rock (this was what I found when I visited our local
sorting office recently).

Sadly I daren't do any welding right now. I spilt a gallon of diesel on
the workshop floor and soaked it up with sawdust, so now I'm giving it
some time to evaporate to reduce the fire risk!

Chris

"Bob Engelhardt" wrote in message
...
Don Foreman wrote:

Yes, you can put rectifiers on a stick welder to make it DC for either
stick or TIG. I've done it. The usual problem is that with a bridge
rectifier, neither stinger (or torch) nor groundclamp are really "ground"
so the work can't be grounded. ...

Why can't the work be grounded? Neither side of the welder secondary is
grounded and the whole secondary circuit is floating.

Then you could. The secondary was grounded on the buzzbox I did this with.
You are exactly right: float everything and then ground what you want
grounded for the job at hand.

I vaguely recall paying £100 for mine in the early 1990s. Don't know
what they would be worth now, maybe less as TIG and other welding kit
seems to have come down in price. You would have to check around your
local welding supplier or keep an eye on ebay. I gave the unit to a mate
on permanent loan but apart from testing it briefly with his buzz box,
which I gave him when I got the Pickhill, he has not used it in about 6
years. Maybe i'll ask him if he wants to part with it.

Christopher Tidy wrote:

David Billington wrote:

You can get add on rectifier/ smoother boxes as well as add on HF
unit. For some years I used this set-up with a Max-arc rectifier and
Max-arc HF unit connected to a Pickhill (like Oxford) 180A oil cooled
welder. It worked well but no current control for ramping. Both units
were purchased in the UK 2nd hand. I think Max-arc themselves are
long gone. The rectifier also contained a choke to smooth the DC.


Thanks for advice. I'll keep an eye out for a used rectifier unit. Any
idea what they're worth in decent condition?

Best wishes,

Chris

Ignoramus408 wrote:

snip

I am in the middle of the tig inverter project (kind of the opposite
to what you do, you want to make DC out of AC and I want to make AC
out of DC), and this project has ballooned in scope fivefold from what
I thought it would take, time wise. I am learning as I go along, and
it is not hugely expensive, but it is a lengthy project. It is near
having a working prototype actually, I hope to have a working inverter
by the end of next week. I would say that I am 60% done. Once (and if)
the inverter works, I would have to fabricate an enclosure, preferably
from scrap parts, and that again would take efforts.

I'll look forward to seeing the finished unit!

Sadly I daren't do any welding right now. I spilt a gallon of diesel on
the workshop floor and soaked it up with sawdust, so now I'm giving it
some time to evaporate to reduce the fire risk!


It must really stink there. I would not even come near it. Diesel fuel
smell gives me a headache every time.

It does. Fortunately I don't mind the smell of diesel too much, but 1
gallon evaporating in a 10' x 12' room is overpowering even for me at
the moment.

Chris

David Billington wrote:
I vaguely recall paying £100 for mine in the early 1990s. Don't know
what they would be worth now, maybe less as TIG and other welding kit
seems to have come down in price. You would have to check around your
local welding supplier or keep an eye on ebay. I gave the unit to a mate
on permanent loan but apart from testing it briefly with his buzz box,
which I gave him when I got the Pickhill, he has not used it in about 6
years. Maybe i'll ask him if he wants to part with it.

Let me know if you/he does wish to sell it anytime in the future. No
need to disrupt his permanent loan, but I could be interested. I can see
that sometime I'm going to need to weld stainless, and besides, it would
be a good skill to learn. Presumably this is a rectifier and a gas
supply unit, but without HF, so you still have to contact the work to
strike an arc? Did you keep the Pickhill for arc welding but get a
full-blown TIG machine yourself?

Best wishes,

Chris

Its just a rectifier choke unit, the gas control is within the HF unit
so that was always last in the system and used for arc starting. I
set-up a few jumper cables with Dinse connectors and so could swap from
AC to DC and back in a few minutes.

I did keep the Pickhill for stick welding and got a Hitachi inverter TIG
with various bells and whistles. It will do stick and should do it very
well but decided to keep the Pickhill for that. As I don't actually do
much stick, as I would use that for 6mm and above fabrication, I have
considered selling the Pickhill to free up space but its not worth much
if anything to a dealer so I would sell privately. One of the local
metals suppliers has had a welder in quite a bit recently to do work and
he has a little thermal arc unit not much bigger than a lunchbox with
him. Bit of a difference in portability to the Pickhill.

Christopher Tidy wrote:

David Billington wrote:

I vaguely recall paying £100 for mine in the early 1990s. Don't know
what they would be worth now, maybe less as TIG and other welding kit
seems to have come down in price. You would have to check around your
local welding supplier or keep an eye on ebay. I gave the unit to a
mate on permanent loan but apart from testing it briefly with his
buzz box, which I gave him when I got the Pickhill, he has not used
it in about 6 years. Maybe i'll ask him if he wants to part with it.


Let me know if you/he does wish to sell it anytime in the future. No
need to disrupt his permanent loan, but I could be interested. I can
see that sometime I'm going to need to weld stainless, and besides, it
would be a good skill to learn. Presumably this is a rectifier and a
gas supply unit, but without HF, so you still have to contact the work
to strike an arc? Did you keep the Pickhill for arc welding but get a
full-blown TIG machine yourself?

Best wishes,

Chris

David Billington wrote:
One of the local metals suppliers has had a welder in quite a bit recently
to do work and he has a little thermal arc unit not much bigger than a lunchbox
with him. Bit of a difference in portability to the Pickhill.

True enough about the portability, but I think the nice thing about the
oil-cooled sets is the 100% duty cycle and the fact that they pretty
much last forever. I don't worry about mine being in a slightly damp
environment, but I would with many of the more complex modern machines.

I'll have a think about the various TIG options and see how badly I need
it over the next few months...

Chris

Chris
you can weld stainless with the AC stick welder...308-16 rod works very well on AC...
others such as 347-15 work on DC only
what is the thickness of the material you'll be welding?

xkvator wrote:
Christopher Tidy Wrote:

I've got a 180 A stick welding set, but it's AC only. I may want to
weld
stainless...

Chris
you can weld stainless with the AC stick welder...308-16 rod works very
well on AC...
others such as 347-15 work on DC only
what is the thickness of the material you'll be welding?

Most likely 2-3 mm.

Chris