Which welding works best for panels?

[oj]

Be careful when using mig wire when tigging - they make a 'pencil' to hold the wire. If held in your hand and the wire grounds itself behind you it'll turn into a heating element in a millisecond and give you a burn that you'll never forget. It happens to regular tig rod often enough but it has enough mass that you have time to get away from it, that mig wire is so thin that it is instant redhot.
I've been wanting to try the silicon bronze thing myself, you'd think after 30 or 40 years of doing this i'd have given it a try. Always another way to get something done and something else to try.

 

[Don]

I use a stitch weld setting on my snap on mig welder, you can set on time and off time ,works great, you can also do same with trigger which i do sometime, don p

 

[Ronnie]

Ronnie are you saying I can still use the sil/bronze mig wire with the tig as long as I use argon gas only? If I have enough success with the mig I won't worry about learning other techniques, I'll have enough to worry about getting my gaps and joins all nice and square to weld nice. Dan.

Yes you can tig weld with that mig wire.I use mig .045" er70s6 all the time on mild steel which is thin.Take about 10 feet of it put one end in your vice and the other end in your electric drill chuck pull it tight give it a few turns and it become straight as an arrow cut it in 18" lengths easy to handle and welds like a dream.You can do that with just about any mig wire. er70s6 er70s2 or stainless just don't use flux core it doesn't work at all.You can also use arc rod for various applications if you remove the flux and get it clean.Arc rod is usually to large for small stuff.
Hope this helps you along.

Ronnie

 

[metalman]

FWIW I'll chime in with my 30+ years rebuilding these old cars professionally.
I hammerweld everything I can even if it means cutting out the inner panels for access and welding them back afterward. Always a butt weld, overlaps causes too many issues. I know overlap welds done with a mig is commen in the industry and it is fast but drive me nuts to see a nice car when its sitting in the sun and that seam shows up because it doesn't expand the same as a single layer.
Originally I Ox/Ac hammer welded all sheetmetal. That's the way an old bodyman tought me in the eartly 70's. Weld an inch, then back the weld with a dolly and flatten it out with a hammer while it's hot and bump out any distorsion. Usally distortion is minimal unless the original panel has previous damage and is already streched (loose I call it) Hit it with a vixen file and move to the next inch. Slow but makes for outstanding results. Done right your weld will dissapper with a little sanding.Used everything from 1/16 real welding rod to coathangers for rod or in my case bailing wire cause we had plenty of it on the farm, it was cheap (free) and it filed easy! 15 years ago I got my tig and been using it every since, same hammer welding process though. Tig is just faster and distorts the metal less plus it's easier to set down quick so you can grab the hammer and dolly then the flaming torch. I keep the panal gap tight, I try to keep no more then 1/32 gap. With the tig I use .035 er70s wire stolen from the mig as rod.
I never understood why anyone water quiches their weld on sheetmetal. The metal shrinks at the weld (that's why you hammer on dolly while it's hot), water quinching shinks it more and work hardens the metal. you want to oil can your panel, hit it with water.
The only time we use a mig on sheetmetal is floors because of the speed and usally not metal finished. I never mig body parts, too hard of a weld to properly hammer and dolly, try working it too much and it will start cracking at the edge of the weld.

 

[36 flathead]

I agree with metalman. mig is great for floors and new cars. tig or torch with hammer works best

 

[Adam/Mill Valley CA]

Metalman, when you hammerweld with oxy/acet, what size tip and what size rod do you use?

Adam

 

[metalman]

Metalman, when you hammerweld with oxy/acet, what size tip and what size rod do you use?

Adam

I used the smallest tip I had ( I think it was a 0) and if it was real welding rod I used 1/16. Most the time in those days I used bailing wire, about the same size maybe slightly smaller then 1/16. Much softer the welding rod though, worked and filed easier and never had problems.

 

[Sid]

I have always found that using a block of copper as a backing works very well for backing when welding large cracks or holes. Also when using a mig stay away from inershield wire. You will want to use either straight Argon or a Argon c.o. 2 mix. It also makes for easier clean-up. I'm not fond of any kind of brass filler as Bondo don't like to adhere very well to it. Just my opion for what it is worth.

 

[metalman]

I'm not fond of any kind of brass filler as Bondo don't like to adhere very well to it. Just my opion for what it is worth.

I've never had a problem with bondo going over silacon bronze done with a tig. Can't state it as fact but it's my understanding it's the flux used in "brazing" that caused the problems with the bondo not sticking, something that use to see a lot in the past when brazing with a ox/acl tourch was used a lot more (before migs became commen in body shops))

 

[cuzncletus]

I weld sheet metal on a part-time professional basis. I work almost exclusively with 18 and 16 ga. All is done with a MIG with hardware store wire. Many times I have to fill gaps, some pretty big. I like a thin gap between the metal I'm working, maybe 1/16 inch but sometimes I have to fill 1/2 inch holes. I use the stitch method. I'll quickly zap some solid metal, then thru the lenses as it starts to cool I feed directly into the puddle again. Experience tells you when to feed back in as it cools; to hot and you blow a bigger hole. Too cool and your weld has pin holes. While pinholes will keep you from certifying on nuclear reactors, on body work they're quickly filled with one part filler.

A good weld, proper temp with wire speed and rhythym correct, will fill gaps with very little grinding to be done. Seconds with a flapper wheel can have it ready for final finish.

Early Ford metal is excellent quality and my educated guess is most is at 18 Ga. There is some thinner (20?) on inner panels, bracing, and fender wells. This can be tough to get the temp and wire feed down low enough to weld well. But with practice and a backer (brass or copper) you can fill this, too. On rusty edges I often cut a tack strip of varying width. Since I'm not going to Pebble Beach or for the Riddler award, I'll put the backer on the less visible side of the weld. Make some holes (drill, plasma) on both sides of the gap and fill a little rosette puddle. Then you can go back and fill the gap. Strong, simple, works great on body panels as it cuts down on distortion because of the added thickness. Am I the only one who uses these crutches?

 

[cmbrucew]

Cus
I have found you must remove the rusted areas, also if you use a backing plate, weld 100% around the backing plate, or the rust will back up between your panel and the plate. You don't want a rust bubble coming thru your paint job.

Works good
Lasts long time

 

[wiretwister]

I havent dont any sheet metal for years but, I always used oxy/Acetylene and the rods I liked best was the thin white painted clothes hanger from the cleaners. I bought a mig 6 or 7 years ago. Don't use it much but like it for most jobs. Sold my old copper wound Lincoln stick last year. Bill in MIssouri

 

[oj]

I just finished welding in a patch panel and i thought i'd show how i did it. I am lazy and don't like a lot of hammer/dolly work, grinding and DA'ing - its a pia and gets the shop dirty.
I don't have a high quality camera, it is an abused shop camera held together with a tye wrap but between what is shown and the explanation you will get the idea.

The first three pics are the patch panel clamped, thats about all the clamping i used and i push/poke the patch panel from the back or front with my thumb for alignment. the 2nd and 3rd pics are the panel tracked, a penny is taped to show how small the tacks are and a shot downward is included to show that there isn't any distortion. the tacks fuze the metal, there were a couple spots that spread and i had to add some filler and those spots haunted me all thru the process.
After the tacking most welders will have to stretch the tacks by hammer and dolly, i resress my electrode (1/16th. To create the tacks i hammer my footpedal and roll the tig across the seam and get off the pedal move and repeat, i don't see the weld form. A small panel as this is and without problems i'll go across it in less than a minute.

 

[Lawson Cox]

Good job.

 

[oj]

Now on to the welding, just like the tacking it is done very fast at highish heat. I start at one end and go straight to the other without stopping. Except for here, the spots where i needed filler gave me fits and my lens was too dark (i broke my lens last week and have a 9 in there now) and i got lost a couple times.
The 4th pic is welded, note the HAZ line - very small. When you have a small haz then the heat is focused only on the seam and distortion is minimal. I didn't use any filler rod.
Something i didn't mention, when i am fitting the panels together after filing etc for tight fit i take a small hammer with a flat face and tap straight down on the edges of the seam to be welded, this will 'pile up' a little extra metal metal on each side of the seam so when i make my pass there will be plenty of metal to work with. As you tap down the length of the metal if you pinch your fingers together and run them across the edge you will feel the extra metal.
The 5th pic is from down the panel - there is a little distortion because of those spots i had to add filler, so i had some hammer and dolly work and i gave myself a goos, stern talking to while hammering.
The 6th pic is inside the panel showing penetration.

 

[oj]

The 7th pic is where i used the edge of a hard disc grinder, perpinducular to the seam, and have dressed it from one end to the other.
The 8th pic i have dressed, tinned wnd wiped the seam and preparing for leading.
The 9th pic i am applying the lead - i heard that sniffing the fumes might be bad for you so i am careful about that.
The final pic is after some filing and DA'ing, not perfect. I'll do a little more work to it but i suspect that a highfill primer would cover any blemishes - some of which was from the file.
So there you have it. Total time was a couple hours and i had to use almost every tool in the shop, you'll notice i didn't pan the camera down to teh floor - the neatnicks on here would've had a heart attack!

 

[Flop]

here is a whole thread about sheetmetal work i did on a 1930 ford. used a miller synchrowave 200 (tig) had my tig for about 2 years now.will never use a mig again for sheetmetal work.also agree with metal man and wonder why people water quench sheetmetal?

this is the link to the complete thread on here
http://www.fordbarn.com/forum/showthread.php?t=23323

fender patch

wheel well patch

 

[oj]

Thats some sweet work Flop. I ain't got to the point where i don't need filler (lead or plastic) but i get closer. I use lead because it is quick and fun.

 

[danliveshere]

Thanks guys for all the replies. Some very nice work in the threads as well. much appreciated, Dan.

 

[Da Tinman]

I think we all have a tehchnique that works good for us, and they dont have to be the same technique.

I skip around tack here there and yonder, dress and dolly the tacks, then start welding here there and yonder till it starts looking horrible, then stretch everything out some and weld some more. Then dress and stretch the enitre seam at once.

I have tig only, I dont have the $$ or the room to have multiple machines so I got the one welder that would do everything I needed. Miller synchro 200 and its awesome!

I dont like silicon bronze for welding up sheetmetal and I use .032 mild steel filler for most jobs.

I have also used mig wire for a more dainty weld,,

Practice is the key here, and with enough of it you'll find your magic way of getting it done. A good profanity stream here and there doesnt hurt either.