Looking for a little help on welder settings...

[jrcflash]

I have a Miller 211 using .030 wire and 75/25 argon CO2 that I need some advice setting up for body work. I am a novice welder. So far I have had good luck welding on the frame adding F250 towers and a rear inboard shock hoop.

Now on to the body. I have been practice welding on some cracking on the under-floor supports. I found myself blowing holes in the thin gauge metal.

I have cut out and am replacing all of the floor sheet metal from the firewall to the base of the tailgate, so I have several hundred spot (or lap) welds to perform.

Please help me with the following:
I have 220 and 110 in my shop, which should I use and why?
Should I use the auto set function on the welder to control wire speed?
Is .030 the correct wire to use for thin body sheet metal?
If not please give some guidelines for speed and metal thickness settings.
I know it takes a bunch of practice to get proficient. Im just looking for some settings to begin.

Thank You

 

[langester]

Does your welder have settings guide on the underside of the panel that covers the wire spool? I have an older miller 250 and 172, both have a pretty handy guide on the door that will get you close. I would also drop down to .023 wire for sheet metal work. You can use .030 but it does tend to burn through easier. Hopefully someone on here has a 211 that will chime in with their setting numbers.

 

[langester]

I forgot to add that the auto setting is pretty cool but I find it tends to run a bit hot for sheet metal.

 

[Explorer]

The auto setting does rather well, But look under the side cover for manual settings, but they tend to run a "little" hot. .030 wire will work, but .024 is used by most people. You just need to do a little more practice and set your welder by welding on scrap metal of the same thickness till you get it right. The 211 is a fine machine, I couldn't be more pleased.

 

[DuctTape]

Are you doing the fill in the hole thing on the top layer with a bottom layer underneath?

I was able to get some nice pseudo spot welds with that method using your same setup. I drilled a hole thru one layer, clamped pieces together, and then basically filled the top hole. For a lap joint this works better than welding the butt end of the two sheets or flanges.

It was awhile ago but I think what I did was take some sheet scrap of same gauge and play around with it until I got the settings where I liked it. I am a novice too and I find that for basic joints with 1/8 to 3/8 I can set on auto and go and do okay, but for harder joints or different gauges I fuck it up, so what I've learned to do is practice technique and settings if it is something more than plain vanilla.

If you are filling holes get some copper, put it on the backside, use same method as above, and then grind the top. Still takes some finagling the settings, I've created more holes sometimes when I was trying to plug them.

 

[jrcflash]

Most of my welds will be lap type where I am filling a hole to connect new metal to the original tub.

 

[Tonka7777]

x2 on the copper plate behind the weld. Not just for holes either. As far as dialing in your wire speed and voltage correctly, watch this video. Lots of other good stuff on his site too.

http://www.weldingtipsandtricks.com/mig-welding-basics-3.html

 

[AxlesUp]

i always used a 110 for light work like sheet metal and 220 for the heavy stuff.

smaller wire will help cool down the weld especially with a 220 machine.

practice makes perfect lol

 

[Whoaa]

That Miller 211 is fine welding machine, one the best in fact!

It doesn't matter to that machine if you're using a 120v or 240v power supply to the machine, at maximum that machine will only draw about 50-60 amps...but no where close to that for what you're doing -not even some 3/16" -1/4" frame welds.

*As a practial matter 110/220 voltage went away in the 1960's. I realize some people still use the terms, but its not accurate. ALL residential electricity in Amercia is now 120/240v, single phase, running at 60 cycles.

Use a copper backing plate for all of you butt welds, and practice makes perfect.

Many of the copper "welding shoes" offered are to rigid and hard to work with.
The BEST copper plate is to make your own from some peice's of common copper water pipe. Take a few peice's of 1"+ copper pipe varying in lenght from 6-10", rip them lenght ways and then pry open and beat them flat w/ a hammer. Now you have the best copper backplate for welding thin material. The thin-ish copper back plates made from water pipe are soft and flexible, easy to form and clamp to the contour to our work. I use a variety of Vise Grip clamps to hold my backing plates.
The magic in all welding is the FITTING. Welding perfect joints are easy, making perfect fitting joints takes a lifetime to master.
With these modern welding machines anyone can push the button and make some decent welds that will be strong. Take a methodical approach to fitting everything, take your time, check everything twice before cutting/bending/forming, *think* 3 steps ahead and plan the fit in your head before you start doing any work. The time you spend fitting will directly relate to the quality & ease of making nice welds.


Form the copper backing plate and clamp into place. Always move forward w/ your welds, and start from the farthest location w/ the first bead, grind off the cold-start glob and back stitch the next weld into the starting point of the previous weld by making the end of your weld blend into the start of the other one..rinse and repeat as you go. Make a habit of laying out the project and ALWAYS back stitching each weld, never welding more than a couple/few inches at a time so you don't warp everything. The grinder is your friend, if there is something that don't come out the way you wanted it to, grind it out and glue it back in place again.

That Miller 211 is a great machine on the atuo setting! It makes easy work, and makes a rookie welder into a decent welder, a decent welder into a good welder. However practice makes perfect and there aren't any other shortcuts for expericnes other than what you've already done..using an excellent welding machine. If you would give your self an honest 4-5 hours of practice welds you would surley be very capable of making some great welds on your thin sheet metal.

 

[Explorer]

Most of my welds will be lap type where I am filling a hole to connect new metal to the original tub.

You should learn this style fairly easily. Floor pans etc, are usually 18 gauge and .030 wire on 220v will work fine. It's taken a while, but I've even learned to butt weld body panels with .030 wire on 220v. A metal thickness gauge is a handy little tool when working with unknown gauge metals until your skills progress. It's like riding a bicycle, takes a while to learn, but becomes second nature. Good luck and enjoy.

 

[welndmn]

I'll echo, nice machine!
Don't practice on rust, go get some fresh metal and practice away.
Go slow, use the copper or aluminum trick under the weld to act as a heat sink.

 

[jrcflash]

I want to thank everyone who replied to my post for help. Each and every word was greatly appreciated.

Thanks especially to Tonka for the link that has lots of good stuff, and also to Whoaa for the extra time spent with your lengthly post. I am practicing...

Thank You all