My old MIG laid down on me and a long time friend (and lifelong body man whose advice I normally don't question) told me I should braze in the patch panels on an OT muscle car. He said he keeps a wet rag handy and "pulls" the heat every few inches to keep the panel from warping. I was with him till he said to use a coat hanger for the rod. I remember watching my Dad braze panels on old stock cars but these are repairs that I want to look decent and hold up. What say ye fellow HAMBers? Is this an acceptable and viable method? A new MIG welder is in my future anyway.
I did a panel-beating apprenticeship 35 years ago and learnt to braze patches on - it takes a lot of practice to control the heat, wet rag and all. A mig welder will let you get the job done much faster, with less practice and less clean up after. The coat hanger would be for welding rather than brazing. I'd get that new mig and get stuck into the project as soon as I could, if I were you.
It's quite apparent there's at least terminology gap, there may be a procedural gap too. You could gas weld with a wire dry cleaner hanger, but today's hangers are kinda shitty metallurgical wise and it's not a something that will benefit you. If you got a stash of 40 year old hangers have at it man. However you can not braze with a hanger unless it's made out of brass and I've not seen one yet. You can get rod cheap cheap. You can get a roll of "tie wire" even cheaper and it welds in nice. It's nearly impossible to braze a butt joint and have it be worth a crap. Butt joint aare the preferred method for sheet metal panels when welding. Brazing works well and makes a strong connection on lap joints but body work doesn't do well on top of lap joints -brazed or welded. Brazing is good on fillet welds too and comes in real handy on special situations.
Did brass many years ago, PITA to clean properly and remove all the flux. Otherwise it will come back and haunt you later. Do it once do it right, MIG
31 Vic has the best response. If your mig has crapped out you can gas weld. Personally I would just invest in some ER70s-6 ( commom welding wire) from a reputable welding supply store. The copper is not there solely to make the rods look pretty. Gas weldings strength in automotive applications is that the impurities are burnt away before the metal can be brought to welding temperature. This can work to ones advantage. The draw back will be a larger heat zone that will need to be stretched out. You will have to adjust your panel fitting techniques if you wish to make it easier on yourself. When gas and tig welding you will benefit from well fit panels with no gap. You may have to invest in some smaller torch tips as well I use a 0 tip I believe but really need to invest in a jeweler's torch. Any welding will shrink the panel and need to be stretched back out regardless of the type of heat source. Brazing is a poor choice for multiple reasons, body work does not like to stick to it, it is weak unless lap joined or has a good cross section to give it strength, properly joined it will not allow for the panels to be metal finished. Sent from my SM-G900P using Tapatalk
I was taught to braze, by my old boss in a custom shop. It worked, but had it's drawbacks. My 55 Olds is still holding up after 30+ year, almost all brazing. But I'd still recommend welding. As 3Vicky said, steel rod is cheap, and will do a superior job, even better than MIG. It just takes some time and skill to hammer and dolly out the warpage.
Agree w/Chopolds, gas weld technique is built over time, Many newer guys use Mig, just a few differences in work-shrink methods.
Gas welding sheet metal is quickly becoming a lost art. This is due largely in part to the speed in which a MIG can produce results and the learning curve to learn to use a MIG vs. gas weld. It takes a LOT of practice to be able to successfully gas weld sheetmetal, control the heat, manage the warpage, etc. While you're saving for a MIG why not see if your "long time friend and lifelong bodyman" will teach you how to gas weld a few panels. Get them fitted up and have him over for an afternoon. You may pick up a new skill and appreciation for a traditional old world technique. Watching a pro gas weld and hammer weld panels is right up there with watching a pin striper lay down some lines: simply amazing and they make it look easy.
Yes sir,I used brass to fill holes where the trim was on my old '65 Ford truck and eventually it will cause problems,especially where you used filler over it. HRP
With brass if absolutely ALL the flux is not removed, in a year or less any filler or paint put over it will pop. Back in the 60's we brazed all the patch panels in the body shops I worked in. Saw a lot of bulged filler when cars we previosly worked on came back with new damage to be fixed.
Several years ago Ron Covel wrote an article for the Metalshapers Assc. about using Silicon Bronze, trade name "Everdur", filler wire on body panels. It was a very informative article and I'm surprised more people don't use it. Less panel warpage, TIG or MIG, and takes paint with no lifting. I don't think the Metalshapers site is around any longer but if you can find the article somewhere, perhaps on Ron's site, it is very informative. I have a copy of it and if you really want it I can send it to you.
What kind of "body man" would recommend brazing panels with old coat hangers? This isn't your back yard in the 50's. Even if it's your back yard in the 2016's you should use a good method that will last, with no filler bubbling. Weld steel with steel. Either with a MIG, a TIG, or an oxy acetylene torch.
I have gas welded using coat hangers. Works fine as long as the flame is rich and you watch the heat. Not commonly done these days and some look down on it. As for actual brazing with a brass filler-- as some have said, filler does not stick to it. It will at first but in a few months it will start pulling up and kill your great body work (been there, done that). Also, having cut out a lot of brazed in trunk panel and rewelded it, I can safely agree with another member that replied that brazing is hard to remove and MIG welding does not like hitting brass. (Some goofball replaced the trunk floor in a 56 Chevy with a panel that wasn't big enough. So he simply cut the filler panel behind the trunk apart and pulled the fenders together to braze the panel in. Worked great until you tried to close the trunk.) I find alchemy's response "What kind of a "body man" would recommend brazing panels with old coat hangers? This isn't your back yard in the 50's." very funny. He posted this on a site that worships old things and old ways. HA!
Before finally buying my Mig welder, I used wire coat hangers from the local dry cleaners exclusively. Never did buy any steel rods at home but did use them at work. I found no difference between the two in weldability! Not sure if the coat hangers have changed though, as that was 20 years ago. Brass CAN be useful in certain areas, but does present problems if any flux is left behind. It's surprisingly strong and we often used it to attach pull tabs to badly damaged areas so that a frame straightener could be used to pull the damage back into shape. Never did see the brass let go...just sometimes bust out the metal it was attached too! You can't "braze" with a coat hanger. Brazing flows the brass rod material over/into usually lapped or fillet joints, but simply melting a steel rod over those same joints will do nothing except make a huge mess. Steel coat hangers get full on fusion welded as the filler material in a similar metal joint.
Don't braze. Filler won't stick. and if you ever need to weld that area, you can't. A brazed joint can (and will) crack. The heat to weld isn't that much more than to braze so you need the same shrink/stretch skills. Finally I have had half a dozen metal slivers dug out of my eyes over the years and all have been brass or cast iron grinding. It will get behind goggles and attack your eye.
Back in prehistoric times when body work was done with brass, yes even at the factory, it was finished with lead rather than bondo. Even then, it had its drawbacks.
You might be the only who read the irony (pun?). I've welded plenty of sheet metal with an oxy acet torch. Chopped a '34 5-window when I was 15 with one, and an A sedan shortly after that. I even filled the top of a '32 grille shell with a tin can lid and welded with coat hangar wire, just to say I've done it like the pioneers did. But I just wanted the OP to understand that brazing wasn't the same as welding. And brazing would bubble his filler later. And he should weld steel with steel (even if it is an old hunk of coat hangar).
Yeah, he said he would show me how and further that I wouldn't go back to MIG. I like to do things once, the right way so it doesn't come back to haunt me.
"The people have spoken." MIG it is. I am going to take him up on showing me how to"braze" though, on some scrap steel. Thanks for the input guys.
I have done exposed seams, on entire quarter panels, from tail light to door post, horizontally, with a MIG welder, with excellent results, and I'm a cracker moron. Time and technique. You absolutely cannot be in a hurry, and you have to fix any deviation immediately, as you will make it worse as you go along. And no coat hangers, ever. If you cannot afford proper welding rod, you cannot afford a hot rod.
I love all the comments that "Filler won't stick to Brass" - I used to be in that camp as well, but what changed my mind was this off topic little truck in the picture. The fender flares were handmade by my buddy and I, and were completely gas welded with Brass Rod and Dipping Flux. The entire surface was skim coated with "Bondo". After grinding the welds we cleaned it with Metal Etch and then Pre Kelano. This was in about 1978. The picture is the truck now, almost 40 years later. Yes the paint has faded from neglect, but the paint has Not popped, bubbled, or otherwise had any adhesion issues.
The body work over brass problem is not caused from the brass, it's the flux residue that's left from shit ass shoddy cleaning afterwords. It's human error and a shit ass shoddy human is going to pass the blame, in this case onto the brass. Your story proves when it's cleaned correctly it's up to lasting as long as anything else. Btw you didn't "gas weld with brass" You brazed with oxy acetylene heat source. Mataterials can brazed with all sort of heat sources
Exactly my point - there is nothing wrong with it when prepped before filler. As for the way I listed it, that was to simplify - Brazing can use MANY filler materials, Brass, (Copper-Zinc), Bronze (Copper-Tin), Silicone Bronze, Aluminum-silicon, Copper, Copper-silver, Nickel Alloy etc. and it is technically known as Torch Brazing. But There is also Braze Welding, and this is what we did. In the simplest terms Torch Brazing is a process of joining the metal pieces by heating the filler material until it is drawn into the space of the adjacent surfaces of the 2 parts by Capillary attraction. Braze welding on the other hand is done by heating the base metals hot enough to "Tin" the surface, (but not hot enough to melt the base metal) and then the filler material is melted onto the tinned base metal, similar to fusion welding. I have also used Silicone Bronze MIG wire when doing seam welding on Unibody race cars.
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