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I watched the CD I got from Lincoln then went to the garage for initial welding practice.

I set the welder on C 4 for 16 gauge metal and laid down a nice bead. I can do beads on flat metal.

Then I tried the butt weld. Oh No. Not good. Now I know what is meant by blowing holes. I turned the controls down to B 3 and it seems to work well.

Any Advice? TIA

When butt welding on sheetmetal just tac and keep moving so You don't get to much heat on the work say 6inchs apart than go back and tac between those welds and so on. To much heat in one spot will warp the sheetmetal don't try and weld it all up at one time better to let the work cool down than tac some more also a little more speed on the wire will give You a colder weld but there is no substitute for practice I got some junk sheetmetal from some old cars and cut it up and practiced alot .


Pete

Dennis,

Butt welds on thin material are very tough to do. The best approach is to design the joint so it's a lap joint...the two pieces overlap. This is much easier to deal with and is often easier than all the exact fitting to get a butt joint.

Backing the butt weld joint with a piece of like material is also an option. Make a butt weld the least desirable joint on your shopping list!

Stuart

I agree with the other responders; what I would add is just maybe some more clarification; If you're burning holes through the metal using a reccomended setting(s) then the problem is usually technique (or lack thereof) meaning operator error. Move a little faster so the heat doesn't get so high and "stitch" weld as suggested. Weld a 1/4" or so and skip 6" then weld 1/4" again. Rinse and repeat.
Sometimes you just have to lower the setting(s); who knows why? Maybe you got a 'HOT' machine, or a cheaper grade of metal or it's steel and not "black iron".
Always do a spark test on unknown metals prior to welding.
You can get a good idea of what you're welding by the color of the sparks created when you grind the metal in such a way as to create sparks. I'm sure you can find out more about spark testing on the web.

I back the welds with copper rather than like material. The weld won't stick to copper. The copper keeps the metal from blowing out. A 3/4" copper pipe flattened on one end held behind where you are welding is the standard made at home tool for this.


Hope this is helpful.
Regards,
Steve
New Orleans

Thanks for the advice. I will keep practicing.

For butt welding sheet metal I make a series of small tacks or s little better than tacks. As I move around, I end up with welds spaced about 1/2" apart. For the next round I weld to the right of each one and run back into the side of the adjacent weld. Finally it takes one weld to close the gap in each little strip. I find that when I grind this down, there are no pin holes.

I also found it hard to see. I missed the mark most of the time.

This must come with practice and experience.

Well I am at the age where I wear bi-focals. So I couldn't hit the mark either because I was looking through my distance lenses. It was too dificult to look through the reading portion with the mask. Then I tried my lenses that I have for using the computer and everything changed for the better. Also if your helmet is adjusted too dark, you may not have enough light.

Make sure the area is very well lit and lighten up your mask. No more whale oil lamps.

I have reading glasses that focus at about a foot and a half at every computer and with every welding helmet. Seeing is everything with wire welding on thin stuff. I also use a real light lens when I weld .025 wire. Mig welding doesn't give off much light and I use a lens light enough to see where I'm starting. I don't care for auto darkening lenses. The heat and wire speed that they recommend is a good starting point, but you have to play with some scrap similar to what you are working with to get it just right.

Don't laugh, I have the auto darking welding helmet and it took me awhile to realize my "transition" eye glasses were getting so dark I couldn't find my work point. I'm near sighted so I can weld without glasses.

It does take quite a bit of practice to butt weld well. Another thing that helps is to chamfer the metal and stitch side to side instead of trying to weld in a straight line.

If you are having trouble seeing when welding go to the welding shop and get a magnifying lens for your helmet. If you think welding black iron is bad try stainless steel.You will have Holes, Holes and Holes! Stainless burns real quick. I don't see how chamfering a butt weld in thin metal will help you as that is making the weld area thinner. Maybe I missed some thing here.
62Blue
Don

My welding 'side to side' got out of hand, too. It looked like a drunken sailor was behind the wheel. Experience and practice must play in improving that also.

I could use more light.

And the smoke. I was worried about that.

I have read too much. And watched too much video.

I need to get some more 16 gauge metal to work on.

What size wire are you using? I've had pretty good luck (and I'm relatively a newbie to welding) with .023 and shielding gas with my Lincoln 140 set on b with a little faster wire speed.

Thanks Mr. Buick. I am using the thin wire. .023 I think?

I found the B 3 setting working at the end of practice session 1. You mention a faster wire speed. In my next session should I kick that up to a 5 or faster? I am hoping to have time on Saturday for the next session.

Also. I buy plate steel from Lowe's home improvement store to weld on. This is due convience and time. Does this metal have a coating that burns or pops or something? Should I be cleaning the surface with a wire wheel or something? I just thought of that

TIA

What is a Lowes? Is that like a homer depot?

Clean the metal well..I even buff off that coating they use on new steel.

Look out for zinc fumes.

I used a higher speed (.023 wire with shielding gas) on my sheet metal patches which were a bit thinner than 16ga. I went to Lowes and got a 2' x 2' sheet of steel and cut it up into 4" squares and went to town. If you're going to be welding up panels, try to get a gauge similar to that which you'll actually be butting together. Here's what I managed to do after a little practice:

http://picasaweb.google.com/ChrisAurit/PhotoHistory#5377946874362322594

http://picasaweb.google.com/ChrisAurit/PhotoHistory#5377947232745876514

http://picasaweb.google.com/ChrisAurit/BeforeAndAfter#5224683405793990546

These were my second or third attempt at butt welding. I think I did the floor panels first because the visibility factor left me a lot of leeway.

I also used those butt-weld doo-dads that Eastwood (and others) sell that really helped me line the panels up.

Thanks again, Buick. Your last picture notes that the doors did not line up and the cab had to be cut and rewelded. Ouch. Thanks for that note. I will do panels slowly and one at a time with adjoining pieces placed to avoid that.

Did you float some filler/bondo after you were done with the welds?

TIA

Pick a certain "heat" or current setting and then adjust the speed to get the proper buzzing and metal flow. With the speed too low you will have random popping and no continuous arc. With the speed too high you high the metal will pile up and you won't get proper penetration.

Thanks Fred. I didn't get back on the practice with the welder. I bought a truck with a real good cab. Just a few spots that need to be fixed.

With the Mig I plan to try the B setting for heat and around a 3 to 4 for wire flow. Lets see how that works.

Thanks again for all the feedback. I am sure I am not the only one to try their hand at this.

Really. It is kind of fun.