Subject: Auto welding . . .

From: Jeremy Kassis <[email-masked]>
Date: Fri, 7 Jun 1996 16:18:42 -0700

What's the minimum amperage you recommend for MIG welding work on an auto?

======================================================================
Jeremy Kassis                                      Stanford University
[email-masked]                        P.O. Box 2631
http://www-leland.stanford.edu/~jkassis            Stanford, CA  94309
======================================================================

---

From: Tom Wagner <[email-masked]>
Date: Sat, 08 Jun 1996 18:31:00 -0700

Jeremy Kassis wrote:
> ======================================================================Recommendation in "Lincoln Proceedure Handbook" is .030 wire, 17 volts 35 
amps.  I use the lowest current on my Lincoln (which unfortuntely is not 
calibarated) .024 and a mixture of 75% Argon 25% CO2.  I try to stitch or 
weld in pre-punched holes much like spot welding.  It is an aquired art 
totally dependant on the metal.  Metal must be extremely clean, most 
trouble occurs when folk try to use MIG on dirty, rusty metal.
-- 

     <<<Tom Wagner, Guru Of Old Stuff and Consumate Collector>>>>
     email [email-masked] URL http://www.island.net/~twagner/
      Home of old British Cars n' Stuff that most folk throw out.
          IF LUCAS ELECTRIC MADE GUNS, WARS WOULDN'T START

---

From: "Jeffrey R. Trites" <[email-masked]>
Date: Sat, 08 Jun 1996 22:37:04 -0700

> What's the minimum amperage you recommend for MIG welding work on an auto?

I have a Millermatic 130 and use it for automotive welding. The gas wire
is great for sheet metal but I need flux core wire to work on the frame
of a full frame vehicle. The flux core is kind of a pain, you have to
scrape the flux off, but it is a better alternative than a bigger
machine for my purposes.

The 130 runs on 115 volts and has four heat settings, which I did not 
think was enough control for welding sheet metal. After a little advice
and a lot of practice I would recommend this welder to anyone.

Hope this helps, Jeff Trites

---

From: [email-masked]
Date: Sun, 09 Jun 1996 23:44:26 GMT

>What's the minimum amperage you recommend for MIG welding work on an auto?

A 100 to 120 amp machine would be the minimum that I would recommend.

I use a Lincoln SP 100 with good results.  It does well with 0.024
wire.  I mix gases, but generally use 25% CO2 in Argon.  This works
well on body sheetmetal.  

I also have a larger power supply and wire feeder that I use for frame
welding.  

J. M. Stuart

Engineer / Inventor / Patentee

---

From: Mike Rehmus <[email-masked]>
Date: 11 Jun 1996 16:53:43 GMT

There is no 'correct answer to that one because the
thickness of the metal more or less determines the
amount of heat you need.

BTW, if you are thinking of using MIG to weld the
automotive skin, make certain you try before you buy.

MIG welds tend to be too hard and the welds crack
when you attempt to surface finish them.  The minimum
strength wire I have been able to find is 60,000 psi
and what you really need is something around 30,000-35,000
psi and little or no silicon content.  That's why
old coat hangers and a torch make such a good hammer welding
setup.

On the other hand, if you are going to weld structural
parts or make welds that can be completely covered by
other material or are on the backside of a structure
like a doorskin welded to a door frame, then a MIG is
a good tool.

I use a 90 amp max rig for body metal and normally
have to turn down the heat to prevent burn-through.
If you have the $, get a unit that has an automatic
spot weld and stitch weld facility built in.

Best regards,

Mike Rehmus