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Mon Jul 10, 2006 6:14 pm

OK...so have done a few panels now and am getting close to the last few ( have also done both heater channels :D ).

But......now that I have put so much time into my project have begun worrying about the pinhoels that I have left in my butt welds. I have found it near impossible with out burn through to get the entire weld solid across. Here is a shot of one of my welds:

Reading in a few generic body work books they say not to leave any holes just to stitch weld right across. I know that everyone has there own opinion on this but am I OK to leave some holes between the two panels? If so what kind of filler would be best for such an application.

This is my first car project and I have never taken a welding course so am pretty new to it all. I just bought a welder and begun with the floor pans and went from there ( thought that would be the least seen area).

I know there are a ton of body work experst out there so don't laugh at my newbie work.....just lookin for some advice or suggestions.

Thanks.

Mon Jul 10, 2006 6:32 pm

I would use all-metal filler, then coat that with finishing glaze like metal glaze by evercoat.

go to www.uschem.com and click on their products, then do a search for all-metal to read the tech sheets. This stuff is supposedly very moisture resistant since its aluminum based.

Mon Jul 10, 2006 6:32 pm

I'm not a welding expert at all, but I use a "brass spoon" if I can get it behind the panel:
Basically get some brass water pipe, hammer it flat and hold it in place it on the back of the hole with a clamp or by hand.
You then weld the hole closed, using a short burst.

Mon Jul 10, 2006 6:37 pm

For the pin holes,Id seal 'em up.water/moisture can seep through and ruin your fillerwork and paint.ITs hard to seal every microscopic hole.Ive havent used Allmetal but Ive heard its good stuff.Kind of like fiberglass gel with aluminum powder in it,sands nice.I used fiberglass resin.appplied it on both sides and took it down.THEN,put my filler on top of that.
Think Id rather fully weld than stitch.

Mon Jul 10, 2006 7:37 pm

Thanks for the advice guys. I was planning on using a seam sealer on the back anyway but might give the copper backing plate a shot first.
I did some looking on Eastwood's site and they have a 'metal 2 metal' I think it's called that sounds like the allmetal filler you mentioned. Was worried about trying to sand it but if it sands OK then I might give it a shot too.
Much appreciated guys. Sometimes just need a bit of reassurance before taking that next step. After all once I drop the cash on paint don't want anythign going wrong for a long time to come.

Cheers from Canada :-s !

Dan

Mon Jul 10, 2006 8:47 pm

krazkayaker wrote: OK...so have done a few panels now and am getting close to the last few ( have also done both heater channels :D ).

But......now that I have put so much time into my project have begun worrying about the pinhoels that I have left in my butt welds. I have found it near impossible with out burn through to get the entire weld solid across. Here is a shot of one of my welds:

Reading in a few generic body work books they say not to leave any holes just to stitch weld right across. I know that everyone has there own opinion on this but am I OK to leave some holes between the two panels? If so what kind of filler would be best for such an application.

This is my first car project and I have never taken a welding course so am pretty new to it all. I just bought a welder and begun with the floor pans and went from there ( thought that would be the least seen area).

I know there are a ton of body work experst out there so don't laugh at my newbie work.....just lookin for some advice or suggestions.

Thanks.

Please don't take this wrong but your welding skills could use some practice, as well as fabrication skills. Flanging the repair panel so you can lap weld would be easier then butt weld's.
Secondly Mig welders and pitts / pin holes are synonymous. I prefer a gas torch not a victor but an aircraft / sheetmetal torch like this.

Tue Jul 11, 2006 5:17 am

You may want to consider lap-welding rather than butt-welding. I use a MIG but I lap welded just about everything on my car. It it very easy to smooth everything out in the end by either tapping in the seam, using Allmetal to bridge the seam, or most likely a combination of both.

Tue Jul 11, 2006 6:41 am

I lap welded my quarters. I thought I was cheating. I guess not.

When you lap weld as i did, what should the filler thickness not exceed? At the present time my filler is the thickness of the metal (20 ga) or 1/20th of an inch.

Tue Jul 11, 2006 6:42 am

About the lap welding, they do sell flanging tools - both pneumatic and manual - that put a nice neat flange on one side. What I particularly like about flanging/lapping is that you can drive a metal screw (those used to attach metal studs) through both to temporarily hold it all in place before welding. You later mig that screw hold hole closed.

The one I have (the one on the bottom) has a punch on the tool as well so you conveniently make holes where you need them. Eastwood, harborfreight etc all sell them - look for "flanger" or "flanging tool"

Manual:

Manual:

Pneumatic:

Tue Jul 11, 2006 9:10 am

Thanks for the honesty...no offence taken ....i realize that I have a way to go in my welding skills. If I were to do this all over again I would drop a little more coni into a better welder too. Mine is a Lincoln but the bottom end gas one. It doesn't have a dial for the heat settings only two switches for Hi and loew , main and fine adjustments so tought to get just right.

I thought about lap welding those panels but it seemd that most folks were against it due to the rust potential between the two panels. Thoughts on that one?

I am installing a ragtop section this week and plan on lapping that one and using plug welds due to it being in a reallly noticable area. Will use a galvanising weld thru primer there first though. Anyone else done one?

Wed Jul 12, 2006 12:38 am

It looks like you butt welded the two panels together using tack welds back and forth, which you are supposed to do to avoid warping the metal.
I've always put a trouble light behind the welds, which easily lets me see the pin holes. Then, I would make a quick, tiny weld over the hole with the mig welder. Then, if I can get to the inside of the panel, such as with wheel wells, I do some stitch welding to fill in the other side and strenghten it.
After grinding the welds (make sure that you go back and forth so there is not to much heat buildup), I would clean it and spread a thin layer of fiberglass reenforced filler along the welds, then sand it. It is strong and waterproof. Regular filler and/or finishing putty then goes over it. I spread it over the welds on the inside of wheel wells that I had welded on two buses to protect them from moisture.
Regarding flanged panels, two of my four left side outer rocker bus panels came that way and the welding was easier. I don't like flanges, though. Old VW buses have a lot of overlapping sheet metal, which is why they are prone to rusting out. Anyway, you have to make sure that the flange on the inside is tack welded in spots to avoid vibration, and to seal it up really well to try and avoid having it rust out.

Wed Jul 12, 2006 8:08 am

Butt welds are a superior technique to flanged welds. Just zap the pin holes with the welder. Your welds have shrunk the metal, so stretch them back out with a hammer and dolly if possible. Here is an article that might help:

http://metalshapers.org/101/jkelly/index.html

John www.ghiaspecialties.com

Wed Jul 12, 2006 1:12 pm

Could you braze the holes shut with something that melts at a lower temp than the sheet metal? Some sort of body solder? It seems like that would be a better option than any non-metal or adhesive fillers/sealants...

- David

Wed Jul 12, 2006 4:36 pm

This quarter repair was done using lap method, but I really think the solution is to grind the repair down, reshape, turn up the heat some, and use many more welds, closer together.....

Wed Jul 12, 2006 7:03 pm

My wife's uncle is a bodyman and suggested I use solder. If the metal is very chean you can flux the area and use solder. Not all solder sticks to steal well but mine worked. I've seen body solder in an Eastwood catalog that may work better. Another tip is to have a damp sponge handy to cool the area after spot welding or soldering to keep the metal from warping. I heated up the area carefully with a propane torch. After a while you'll get the feel for it. Whats nice is that the solder sands down easy and looks great.

Dave

Wed Jul 12, 2006 8:30 pm

krazkayaker wrote: But......now that I have put so much time into my project have begun worrying about the pinhoels that I have left in my butt welds. I have found it near impossible with out burn through to get the entire weld solid across. Here is a shot of one of my welds:

Reading in a few generic body work books they say not to leave any holes just to stitch weld right across. I know that everyone has there own opinion on this but am I OK to leave some holes between the two panels? If so what kind of filler would be best for such an application.

This is my first car project and I have never taken a welding course so am pretty new to it all. I just bought a welder and begun with the floor pans and went from there ( thought that would be the least seen area).

Lemme guess -- you were trying to weld a long, smooth bead across the whole thing? That technique works great on thick metal but with thin 18-gauge VW metal (not to mention 20- and 22-gauge aftermarket panels), you'll keep warping and blowing through.

Best thing to do is to keep the heat down, the gas up, and weld LOTS of little stitches like this guy: http://www.metwiz.com/june06/page2.html

Also, your local community college/tech school should have a MIG/TIG welding class -- money well spent. I personally had a blast at mine! :)

Wed Jul 12, 2006 9:06 pm

As a rule, I always turn the heat up when tack welding. Better penetration and less chance of burn thru with tacks...than trying to get a bead on sheet. Sheet also warps massively when stitching.

Sun Aug 20, 2006 6:17 am

Thanks for the advice all. I will try to combine all that insight and get back at it.
John....great article...thanks for putting the time in to get that out there for us. (PS. are you the same guy who sells the metal shrinking disks! I bought one and it's great by the way!)
It' funny how the lap vs butt weld debate comes up so often. I know some say it is the only way and yet a pro body guy I talked to last week says that they were taught in school to lap and that is how he does all his repairs.
Enjoy the rest of the summer and keep the advice coming! I know there will be others with the same questions and appreciate the help.
Dan

Sun Aug 20, 2006 7:37 am

Hi Dan,

Yeah, thanks that's me. There is a big difference between what body shops teach their workers and what a true restoration shop will do. It is not unusual for do-it-yourselfers to do better quality work (in some ways) than a body shop. Lap welding is easier and faster, not better.

John www.ghiaspecialties.com

Wed Aug 23, 2006 2:39 pm

John Kelly wrote: There is a big difference between what body shops teach their workers and what a true restoration shop will do. It is not unusual for do-it-yourselfers to do better quality work (in some ways) than a body shop. Lap welding is easier and faster, not better.

on average, a good modern body/collision shop produces fast work with quality acceptable to the everyday person in a time frame pre-determined by insurance companies. there is no comparison to a restoration house.