I want to 'shave' the doorhandles on my Olds, going from the original protruberant chrome loopies to some modern recessed/flush-fit badboys. To do this, I'll need to patch in a small new panel, and I want to absolutely minimize any warpage- I'd rather not make it, rather than try to fix it later. Now, I've done plenty of sheetmetal welding, both MIG and oxyacetylene, but I've rarely been worried about warpage. And so it usually does. The Olds doors are huge, long and kinda flat, and the car's gonna be black- that puppy needs to be straight. The problem is, everyone seems to have a "pet" method, and sometimes they contradict each other. Weld, then quench with a wet rag, or weld then smack with a hammer and dolly, or weld and don't worry about it, you can hammer it all back into shape after it's done. Some say butt weld, others say flange it, tack, then fill with kitty-hair bondo. Some say TIG is best, others say OA gives the best results, some say MIG minimizes warpage, a few still say "braze it". On the third hand, some will say the MIG weld will crack, especially if you quench it, others say the OA oxidizes the metal and makes it brittle. What do you guys say? I'm confident I can shape the insert pieces to fit fairly well, and I have both a decent MIG and a gas torch available, and shortly a TIG. I don't mind spending the time to do it right the first time, but I also don't wanna use these doors as "practice". Doc.
See if you can find some other doors to use as practice! it could be worth the effort if you screw up a practice door instead of the real thing. I'd lap and mig weld it, but I don't mind having a thin layer of bondo on my junk.
Dude, you are listening to way too many people that don't really know about metal working either and are telling you what they have heard from people that really don't know what they are doing either. The reason the metal warps is because the weld shrinks as it cools and pulls the surrounding metal in toward it. So after you weld something it's posable for the panel to pucker or sink a few inches or more away from the weld area but what's causing the warpage is only the weld, so that is what needs to be addressed. If you plan on correcting any kind of warpage after a weld you have to butt weld the joint. Flanging and overlapping the area is completely out of the question. Don't even think of Brazing! And the MIG is a brittle weld that tends to crack when you hammer on it to reverse the shrinking. Gas weld or Tig is the only method of welding that I recommend if you plan on a repair that you can work the metal after the repair. So now with the knowledge that it is the weld that makes the panel warp and nothing else that area is the only you need to workout to reverse the affected area. The worst thing one can do is try to work out the warped area without dealing with the weld area that actually caused the metal to move in the first place. All you will do is cause way more damage to the panel. So, once the panel is welded and there is some warpage the method for reversing is to plannish the weld. This done by using the hammer and dolly and hammering directly on the weld. Remember this is the area that shrunk and pulled the metal in so my hammering directly on it you will make the metal grow slightly and relax the surrounding area and the warpage will be reversed. Think of what happens to bread dough when you pound on it gets bigger and flatter right, the same thing will happen to metal when you hammer and dolly directly on it. Just be careful not to hammer too much because you will make it grow too much and that's what causes the oil canning. Then you have another problem in which the metal has gone the other way and you and to shrink in instead of stretching it. Confused yet IF you want to see how the hammer and dolly on the weld works to relive the stress on the welded area, take a couple of pieces of 20 gauge sheetmetal about 6 inches square and butt weld them together and let them warp, trust me they will. And then hammer the welded area only and watch the two pieces flatten right out. And it will give you a good idea of what is happening to the metal. The trick is knowing what the metal does when you weld it and how to reverse the process.
Now that's some info. One of the main 'conflicts' I keep hearing is whether the weld shrinks too much or doesn't shrink enough. I've heard both- like above, which says the welds shrink further than the original metal, and others, which say the weld bead, being thicker, doesn't shrink as much as the original metal. Naturally, one wouldn't want to shrink the former any further, and wouldn't want to stretch the latter, if they were true. Doc.
the new part is going to shrink more then the old metal of the door due to the fact that the section of late model door handle pocket will be half the thickness. to me it would be more important not to warp the insert for the flush handle.
I thing with metal working it realy does take lot of practice to get good. good metal guys will tell you they are still learning all the time and they learn from others and by just doing it. There is a saying...Be smarter than the metal. BUt metal is not stupid and can be sly and always wants to trick you up.
early customs were called "lead sleds" for a reason. panelwork that leaves a car ready for paint without any smoothing is VERY difficult, and in the opinion of a man who does NOT have the ability - nor the time to learn it unfortunately - to metal finish a car, there's nothing wrong with a bit of filler. i doubt there's a black car out there that doesn't have filler, and if the guy says it doesn't, ask the panel shop that painted it for him how many coats of hi-build primer they used. just to back up rudy's much more learned opinion than mine, i CAN say from personal experience that MIG welds are VERY difficult to work afterwards, and crack. not only that, but it's harder to avoid blowing holes than it is with TIG. i've only just got my Henrob torch and haven't even got the regulators yet, so i can't say anything about oxy just yet... it's not long away though!!
Thanks, And trust me I use filler. But I make a point to have a good foundation and I feel the repair or modification will last a long time. I do Frame and body work for a living, Bondo is my friend
Make a up a stand for Oxy- a bit of sheet metal with a V cut into it and weld it onto a bit of inch square tube, weld this to an old brake drum , next get a nut and screw it on to the tip of the torch about an inch from the end- the tip goes into the V and the nut keeps it there. Cut a bit of metal the same gauge as the panel Clean up both sides of the panel at lest ¼ of an inch of shiny bare metal around the area to be welded. Get comfortable so you can reach the back of the panel with a dolly and the torch (in its stand). The piece to be welded in should be the same size as the hole (but weld). TIP- use a magnet to hold the patch in place. Do a tack no more than 1/8 th of inch and while it is still glowing red, place a dolly behind and TAP with a hammer- no need to bash the shit out of it- just 4 or 5 taps. Now for the hard part- LET IT COOL !!!- don't do another weld until its cool enough to touch with your bare hand. Work your way around a little weld, tap tap tap ., wait, weld, tap tap . Clean it up with a flap disk and prepare for paint.
I agree with roadstar. TIG or gas are the only real ways to do this. I prefer the TIG, it let's you make tiny tiny takcs all over without putting any substantial heat in the area, and it hammers very well. Like several others have said, practice makes perfect, better to screw up some scraps first
ROADSATR / SPARK: I'm trying to learn O/A welding so thanks for the great info! Im curious about the hammering of the weld. At what point after the heat is removed should you begin hammering the weld? Should it cool entirely or should you hammer while it's still glowing? With O/A on a patch panel. Should you do small spots/tacs OR should you try to run a continuous weld? If so, how long of a continuous weld should you run before you stop and let cool? THANKS AGAIN FORTHE GREAT TIPS
Keep in mind it is still shrinking while it is hot. So I prefer to wait till it cools enough to rub my hand over it. Also I will grind the weld some so I don't hammer the weld material instead of the joint. IT tends to leave an edge.
Simply avoid putting too much heat into the panel. A TIG is great for this. I like to Oxy-Acetelyne only on curves, because of the heat. You can stitch weld with a MIG, putting a small bead of weld here and there, rotating around the insert panel so that you don't generate too much heat. That's the way I would go if I were you. And don't use too new door handles. They just don't look right. They're worse than billet, in my opinion. Hide some solenoids, or some other trick. But a traditional rod or custom with Honda (or late American or whatever) door handles just makes me cringe. --Matt
I'm going to go with Matt on this. I have no welding advice because I am an amateur at that, but by all means shave the handles and fill'em. But after that, just do some solenoids and poppers. It'll be cool, I promise.
-Well, except for two things. First, it's not a "traditional" rod/custom, it's a '66 Toronado, and second, it's Alaska, and the car will be more or less a daily driver. Doors can and do freeze shut. Doc.
Yes tap the weld while it is still glowing - stop when it loses colour small welds about 1/8 of an inch as soon as you take the heat off start taping the weld, stop when it loses colour, now wait to the whole thing cools enough for your to run your hand over it (Important), do the next 1/8-tap tap...cool... no long runs will put way too much heat into the panel = lots of warping small weld then taping the weld with adolly behind, let it cool- this takes a while but will give a good result. .
I admire the Tig welders and their restraint and their respect for the metal etc-etc......But it simply can be done just as well with a Mig welder. Besides MANY rodders do not havd a TIG. Cut your opening for handles and then cut your new handles to fit that opening AS CLOSE AS POSSIBLE. That is the big thing-it must FIT. Yes ,heat is a big factor and the "secret" if there is any, is to not warp it to start with . Then all the pecking and shrinking/planishing, wont even be necessary at all. I do a lot of modifications and patch panels myself so here is what I do. I'd suggest all peices be as clean as [possible onBOTH sides to start. Contamination[smoke] from them can negate your Inert gas's effect on your mig welding job. This mixed gas's job is to evacuate the OXYGEN from the weld area-it cant if its overwhelmed by clouds of smoke from paint or undercoating or even a poorly cleaned rusty surface. That being said, a second important point is this: DO NOT weld any beads of any length on sheet metal. Its just too much concentration of heat in one place at one time. I'd suggest rather, that you turn the welder up to a mid or high setting and do just instantaneous /split second ,hot tacks lasting no more than a second . Doing this and moving around a lot by spacing the tacks is the secret. Then use your other hand to guage the overall temps in the panel..If it becomes UNCOMFORTABLE - enough to not be able to leave that spare hand on your work -THATS TOO MUCH HEAT!. Notice that I didnt say HOT? IF ITS BLUE ITS TOO HOT. Theres no need to have to straighten it -if you dont warp it to start with...... another trick that helps in some instances is to have your blow gun ready and blow it cool as it needs it[ if you were afraid it had absorbed too much heat] in a single spot. This welding method will work well as the higher setting will give you a weld that has penetrated enough to accept the final grinding and leave an adequate weld to stay together for years of use and vibration. I have seen several chopped tops that I have done ,using this method of welding- that are still wearing their original body work ,after twenty years,and still look good.
the best advice i can give you is to TAKE YOUR TIME!!!! do not get in a hurry or you will end up spending more time in the long run fixing the problems caused by rushing. if using a mig, stitch weld that sucker in there...go slow...tack at the 12, 3, 6, and 9 o'clock positions...once you get your first tack on there, your patch should be held in place just fine...so take it easy...then go back and tack between your existing welds. till it's all done... as long as you take your time, work slowly, and don't heat that metal up too much, you should be able to get away with only a skim coat of body filler.... i have had very good luck with the flap- disks for knocking down welds...they seem to work more efficiently than the standard "stone" grinding disks.. the less time you spend heating up the welds againby grinding, the less potential for warpage again. just my 2 cents
Personally, I'd prefer the original Toronado handles over something more modern. (What are you planning on substituting, anyway? For frozen doors, what's better to yank on than 1960's GM door handles?) Also, check out John Kelly's link, and ask him any questions, because he knows what he's talking about. --Matt
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