Welding Question

[BLKRuby]

Hi all! First off i am a newbie in fabricating and welding. I am building some sliders for my JK and have a question for you all.

I am using a 230 MIG welder, 3/16" square tube, and schedule 40 pipe.
I have everything cut and tacked together. I have been doing the welding at settings 3, 65, and about 12psi, ( it's not my MIG, don't know what gas, but i think it is CO2?) with 30 solid wire. My tacks are fine, but i am concerned about the finish welds since they will be crucial for structural support if i do ever come down hard on them.
What set up would you guys recommend for this? This may not be the best description for you all, but any additional help would be awesome.

Thanks

[nsscout]

first question would be is what kind of mig welder are you using?

i have a miller dvi and it has 6 taps. for 3/16 or 1/4 i generally run on the 4rth tap and about 50 or 55 wire speed. 12 psi is too low for shielding gas flow generally 20 to 25 is norm. i am also running 035 solid mig wire.

hope this helps and good luck with your fab project

[fj40forlife]

I got mine about 20 psi and its working great...

[GiantTechGuy]

I'd take some scrap pieces of the same materials, weld them up then slice em in half with your band saw and take a look see for the penetration.

[BLKRuby]

It is a Weldmark 187 i believe. Not the current model though, a few years old if that helps.

[BLKRuby]

Originally Posted by GiantTechGuy

I'd take some scrap pieces of the same materials, weld them up then slice em in half with your band saw and take a look see for the penetration.

What should the inside of the welds look like? any pics maybe?

[GiantTechGuy]

Originally Posted by BLKRuby

What should the inside of the welds look like? any pics maybe?

You don't want it to look this this! See how the weld is basically just sitting on the more vertical peice.

[GiantTechGuy]

This one did not pass the hammer test

[GiantTechGuy]

This one is a little better, see how the legs of the weld appear to have penetration? Especially the left side weld.

[Stephenw]

The gauge for your shielding gas is a flow meter. It does not read in psi. It reads in CFH (cubic feet per hour). In most cases, you should set your gas flow to 20 CFH. Many flowmeters do have a PSI gauge, which reads pressure remaining in the bottle. That is the 0 to 3000 PSI portion of the gauge.

[Static-XJ]

Originally Posted by Stephenw

The gauge for your shielding gas is a flow meter. It does not read in psi. It reads in CFH (cubic feet per hour). In most cases, you should set your gas flow to 20 CFH. Many flowmeters do have a PSI gauge, which reads pressure remaining in the bottle. That is the 0 to 3000 PSI portion of the gauge.

Most light duty wire feed welders come with a calibrate orifice regulator, not a flowmeter. A known pressure, through a certian sized hole, will yield a certian flowrate. Here is a pic of the one I got with my little welder:

Right is the pressure in the cylinder, left is the approximate flowrate. I've never used this one, the sticker on the right says it's for argon and argon mixes only. Left guage reads CFH, even though it's only an approximation. These aren't as accurate, or generally as durable as flowmeter regulators (what you posted).