Learning to Weld - I finally got a welder. - PeachParts Mercedes-Benz Forum

300SD81 · #1 04-13-2008, 07:05 PM

Haven't been on here in a while since my car got wrecked and I've stopped working on it except for regular maintenance...no point fixing the little things or upgrading anymore... I finally found a welder thats in my price range and bought it. Astro Tools MIG11 110amp with a gas bottle and welding mask for $80. Does anyone have some good tips or a link to a website on how to get started? I've tried welding some scrap metal but the welds turn out crap. I think I probably have the wire speed set way off or I'm not holding it still enough.

Zeus · #2 04-13-2008, 07:14 PM

Nice score! I welded a new floor into my old 280E with a mig welder. Got some really nice beads. My (limited, unprofessional) experience was that the following made a big difference -

1) metal surface prep - metal has to be REALLY clean to get a good weld.
2) good ground/connection
3) gas flow rate - had to play with this a fair bit to get it at the right setting
4) voltage - same as above
5) wire feed speed - same as above

Took some fidgeting and experimenting, but you should be able to get some nice work done if you take your time. I can't emphasize making sure the surfaces are clean, bare metal. That was my biggest challenge. Other than setting the undercoating on fire, but that's a story for another time.

KarTek · #3 04-13-2008, 07:18 PM

Take an "adult/continuing" education class on welding at a local trade school or college. There's nothing like an instructor right there to help you along.

Here's a couple tips on getting started on the MIG.

1. Weld forhand. That means if you're right handed, hold the tip against the surface angled to the left and while welding, push it to the left.

2. Do a practice sheet. Take a flat piece of sheet metal and make a pass across it. Observe the results and change something like the voltage - say, bump it up a notch and make another pass observing the results. Keep repeating this in a systematic manner making a small change either to the feed rate or the voltage until you get a feel for what the adjustments do to the weld quality.

tankdriver · #4 04-13-2008, 11:01 PM

Do you know anything about welding? You're supposed to make little overlapping circles, kind of like you're stitching it together.
As for heat (voltage), too hot and it'll burn holes. Too cold and it'll make a tall mound instead of being flattish.
Wire speed, if it's too slow, the heat will melt the wire up near the gun tip and you won't get a steady run. If it's too fast, the gun will push back in your hand.
Travel speed, go about this fast

. You're on your own for that one.
You'll have to kind of tweak the three together. The hotter you weld, generally the faster the wire speed has to be. Travel speed should be constant.

BoomInTheTrunk · #5 04-13-2008, 11:24 PM

alright i have taken a class on welding and have worked in a welding position so i know alot. Here are some basics.

1. clean metal, good ground all that stuff that was mentioned earlier.

2. set your wire speed and voltage about 1/3 of dial setting maybe even alittle slower. but keep the two low for beginning, to low and it will start to pop sort of.

3. if you have noticed when you have played around you will notice that the weld that you are making becomes sort of clear you want to keep that consistent. If it is not clear looking than you are not getting any penatration. remember a good weld has penetration.

If it was me i would cut some 2 inch by 2 inch squares of metal and just practice multiple beads on that small piece of steel.

all right you see the third weld that is the best you should have penetration through the piece of metal you are welding. The settings that i gave you are for like 20 gauge metal and close to that. gas and wire speed should be close to the same on the dials. Hope this helps you and if there are any other questions just ask.