With all the welding coming up on the -6 car I purchased the MIG conversion kit for my Lincoln. It is much cleaner and has better penitration but I'd like to get some feed back on where to set the PSI for the CO2/ Argon mix. Want to have enough but not waste it either.

seems to work well on 16 gage steel with 20psi

I use 31-32psi. I use .023 wire and argon/co2 mix.

I use 25-27 psi with .023 wire with good results. You need just enough flow to prevent oxygen from getting to the weld. Oxydation (also known as rust) is bad for the weld and for the metal the car is made of. That's just a beginners opinion. Hopefully we'll hear from some of the experts.

Wow I'm using about(edited see below) 20PSI. Lincoln HD175 it is a 220 volt model but I dont think that would matter much. I use Lincoln wire Super Arc L56 it is .030 .. I have went through 4 of the 2lb rolls on my 914. and just got the bigger roll this time I forget the size of my tank it is about waist high, and it will last just a little better than 2 rolls. When I have welded outside on other projects I have turned up the psi due to wind.. going from the flux cored stuff you will love it.dont forget that roller feed wheel needs to be flipped for different size wires, and going to gas welding I had to switch the connections in the welder, on mine at least...

Ok I had to go look at my manual... and my welder.. oops there are 2 sets of measurements on my gauges, it appears that 10 CFH which stands for Cubic Feet per Hour is the same as 20 Psi,,, DUH so your right there.. sorry

Solid wire should be DCEP or Elecrode Positive.

Flux core wire should be DCEN or Electrode Negative.

That's as per the manual for my Millermatic 180. Your results may...

Yes, you need to reset the polarity of the welder. I can't remember where I came up with 31PSI, last time i was doing a lot of welding I was getting a lot of outside wind, anyways I think I fooled with it to where I liked the results.

I have an AC/DC Lincoln Tombstone welder. Did you put this conversion kit to a stick welder?

....b

Yes, if you convert to 3/8" body panels...

No, I mean the mig kit I have been welding aluminum with the stick with great results and thinner body panel stuff also. Migs are just easier.

......b

thanks for the input guys, the kit came with super arch ,023 wire and I guess Im in the range unless the wind is blowing, I did switch from flux core and changed from Neg. electrode to positive.

Andy,

AWS suggests.....and back in the days when I was an ME........ haven't been one in years cause we don't make anything here (US) anymore...... an 80% argon mix to 20-25% Co2 mix for carbon steel for thicknesses of less than .125. For over .125 use a 50-50 mix of argon C02. For non-ferrous a "tri mix" is best, that would be 90% helium 7% argon and 2% Co2.

Flow rates of the gas will depend upon the transfer type...this is the arc transfer..this is difficult to describe but basically the voltage drop across electrode to the base metal. Also it will depend upon the conditions you are welding in and the cup you are using to sheild the weld surface plus the thickness of the metal you are welding.

I have found that most instances about 30 CFH for a flat position weld should be fine. Since C02 is heavier than air then an out of position weld will require more CFH for adequate sheilding. The tri mix is really expensive so most folks use Co2.

Hope this helps.......

If you need any help...which it doesn't look like you do... by your car.... let me know.

Rob

Thanks Rob,

its $35 for a refill of Argon/CO2 on my half bottle. A few pics and the mix ratio from the local Airgas dealer. I ordered a cart after checking the price versus building one. It's not as portable as it was before

Now get busy and weld up a little cart with casters for that stuff.

Holy beegeezus !! You guys are wasting ALOT of gas !! 12-15 cfh is ALL you need unless you are welding outdoors. 75/25 mix, .023 wire and 15psi is all you need for anything on a 914, unless you get to welding on the suspension. Even then you won't need any more gas flow, just larger wire and higher amperage.

And for all you folks that think you need to buy a 300 amp machine, all I have at the shop is a 140 Miller MIG and it is all I need on a car. I do have a 250 at home and a 200 amp tig, but the 140 mig is all I use at work for body work.

I've never used more than 15 psi

I have pretty much the same welder, but mine is the 135. I run my gas (C25 same as you) at around 15lbs on the trigger. I believe I got that from the Lincoln manual.

Yes...checked.... 15-20 CFH should be okay for 1/8 steel....our little cars unibody is just sheet metal. I am used to bigger stuff. You guys though are talking about 15 psi which is pressure...flow rate is different. I think somebody else already said that.

Keep a short arc length...hold the end of the arc close to the base metal..short arc transfer is better with Co2.

Have fun on your new car Andy.

Rob

the man has spoken, and it has been declared.


Really could you post like an FAQ of wire size and gas etc. for various areas of the 914? I am getting ready to do a bunch of stiffening stuff and seam welding. Also a couple 1" patches here or there.

I would wish 10 million x good karma upon you and your ilk for generations to come. That kind of knowledge is awesome.

I've been using 12 psi for years now. But I'm always welding indoors.

I'd have to go out and look, but I think the last time I set mine, 15 psi wasn't quite enough for given situation and I bumped it up to 20. I'm always welding in the garage and the door is usually open. Perhaps that's why. But I haven't touched it since then as it gets the job done and I'm not screwin with it constantly.