I'm chopping my 28 tudor and having a bitch of a time tacking the 2 pieces together. I read that with the high iron content that its hard not to. Pretty much as soon as I touch the trigger theres a hole. Its a millermatic 250, 035wire heat all the way down. Would thinner wire help? Anyone have any tips? thanks
The .035 wire is small as it is. I would say try turning up the wire speed up a little and keep the heat down. You might be to hot for the wire speed and it is wanting to go into a spray type weld. PM me if you have any more questions. Thanks
Are you MIG welding or using flux core? Flux core is too hot for sheet metal, IMO. Also, been my experience that .035" is too big a diameter wire for sheet metal - carries a lot of heat. Try the smaller (.023") wire with C25 gas and practice varying speed & tap setting with some scrap pieces of the same thickness material to find the right adjustments. Just spot weld it, allowing it tool cool before making another spot weld. Don't try to run a long bead.
Another train of thought,,,pick up that grinder in the floor and grind the paint off,,,clean metal welds much better. HRP
If you are running a flux core and switch to gas, (on my machine anyway) you have to reverse your polarity.
it is ground clean mig welding just a spot weld, as soon as it hits the tin it blows through. I have varied my wire speed up and down with no luck. I should have done this before I sold my hobart 140 Please note, I am not new to body work. I have experience with newer metal and know pretty much how to do it without fucking up to much. As soon as my wire hits the tin it blows a hole, I cannot consistently get a tack. The metal is still in pretty good shape, its not paper thin or anything and the cut gap is tight.
Yeah no kidding. it might also help if you use .023" wire too. I think larger wire has a higher volume of heat needed to weld. Somebody correct me if I'm wrong, but I'm about 80% sure.
yes you are right use .023 or easy grind 20 gauge wire made by harris.try copper behind the panel also.
You might pm Choprods or maybe he'll chime in here.I've seen him weld 2 pieces together that were so rusty you could see through them.He was using a mig at the time.................Greg
the planets must be aligned now, today it is going much better. I got the old lady out to help with some metal behind and it is actually going very good. Thanks for the replys
This is how I do it. .023 wire, higher heat, and faster wire setting. This way you can get on and off Faster and actually produces less heat on the panel. Also what gas are you using. If it's pure C02 because you want to save some $ Then your gonna have trouble. This is really not meant for light welding. The best gas to use for this is the argon 70%, C02 30% mixed gas. It provideds a much more controlable weld. With this set up you can actually weld up to 1/4 inch plate with good results as long as you v-butt the joints and take your time doing a good fillet weld.
Like they all said.....023 wire...even .030 is OK for sheet metal, but 'iffy' when doing grinder thinned areas, or rust eaten areas. .035 wire is HUGE for doing sheet metal! I sometimes even use 0.030 on frames, I don't like the way .035 melts.
So I'll probably go buy some .023, tip & rollers for my mig. And just finish the chop when I finish the rest of the body work. Which theres lots. It was actually going pretty good today but I'm feeling impatient so I figured I should not be doing body work today lol. I'm using a Argon/Co2 mix 90/10 pretty much all I can buy here, praxair Migmix gold. Thanks for all the input.
Check your rollers, mine reverse for the different wire size. I had the same problem with blowing through until I got some .023. I still suck at it and blow through a lot, but that's operator issues...
Use .023 wire with argon. Flux cored .035 wire is for farmers and frame builders. And if ya can---get a peice of copper about 1" square x about 8" long to use as a heat sink. Grind a very slight convex shape to the 1" square end (not concave) so the copper can be held against the inside of the body as you are welding the outside. Have someone hold the copper by the long end---and wear gloves, because it will get real hot, real quick!!! The copper acts as a heat sink to prevent burning instantly thru the old sheet metal. The copper will not melt nor stick to the weld, and it will let you 'puddle" the weld a bit as you go----and remember to skip around to prevent heat build up and warping.---Brian
great idea but I don't have oxy/acetylene setup, and don't want to buy one yet due to all gas cylinders here needing contracts. Brian are you saying pure argon with .023? I have a spool gun and am looking at getting an argon cylinder for stainless and aluminum, but haven't justified another contract for the little I do. I will keep the .035, I'm not a farmer but I do build frames.
Straight Argon won't work with steel. He was refering to straight co2 to weld steel. Its cheap gas and gives deep penitration, which is not what your after for sheet metal. If you want to use the .035 wire, turn up the wire speed a bit with the heat set low. The idea is to have just enough heat there to melt the wire and steel. Welding sheet metal with .035 takes a lot of practice. The problem with old sheet metal is you really have no idea how much thickness was ground off to get it clean. I really dislike .023 wire, but then I do a lot of different things with my welder all the time. Gene
one thing that i find works good is to use a "heat sink" you cant weld brass so try to find a big flat piece of brass of good thickness place it behind the spot that you are welding. prep the spot very well use a thin wire low heat and high wire speed. the brass will help to keep from burning threw by taking some of the heat away.
I discovered that a little gap [ 1/16th of an inch or so] between the panels made the welding work MUCH easier.. I aso didn't weld straight on at 90 degrees to the work, but came in on a fairly steep angle from the side. Low power 030 wire....
weird, thats what I had to do to begin with, go on a steep angle into one piece then bring the tack quickly to the other piece. That was about the only way I could make it work.
hello i have a 30 tudar and im looking to relocate the gas tank ...any tips also thanks to all of you for the welding knowledge all tips are welcome
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