I’m working on my 64SS quarter lip area. I cut a patch panel from a parts car to weld into the rusted area. After an extensive searching/reading session my first choice is to use the Tig/hammer welding method. I have a few questions up for discussion... or point me to the thread that has already answered them. What’s the best way (meaning best way for hammer welding) to cut and fit the patch? Should the panels be fit as tight as possible (no gap)? Should the weld be quenched or cooled in any way or let to cool on its own? What type of filler rod to use? I was recommended this stuff for sheet metal http://www.airgas.com/browse/product.aspx?Msg=RecID&recIds=250760&WT.svl=250760 cuz you can use really low amperage. Or should I just use standard ER70?

Second choice would be to just mig butt-weld it... so same questions about cut, fit and gap or no gap. Quench? Also heard if done right mig will put less heat into the metal? In the long run is it worth the timesavings?

I’m working on my 64SS quarter lip area. I cut a patch panel from a parts car to weld into the rusted area. After an extensive searching/reading session my first choice is to use the Tig/hammer welding method. I have a few questions up for discussion... or point me to the thread that has already answered them. What’s the best way (meaning best way for hammer welding) to cut and fit the patch? Should the panels be fit as tight as possible (no gap)? Should the weld be quenched or cooled in any way or let to cool on its own? What type of filler rod to use? I was recommended this stuff for sheet metal http://www.airgas.com/browse/product.aspx?Msg=RecID&recIds=250760&WT.svl=250760 cuz you can use really low amperage. Or should I just use standard ER70?

Second choice would be to just mig butt-weld it... so same questions about cut, fit and gap or no gap. Quench? Also heard if done right mig will put less heat into the metal? In the long run is it worth the timesavings?


First off,
A tight butt weld with NO gap produces the least amount of warpage and also the easiest to weld. Plus a TIG likes tight panel fitment, if need be tack it with a MIG to get that tight fit then TIG.

Second,
NEVER NEVER NEVER cool the metal after welding!!!!
Allow the weld to cool on its own.

Most guys who TIG sheet metal use .023 wire right out of the MIG welder.
No point in using something fancy. One trick is to clamp one end in a clamp then chuck the other end in a drill. This will give the wire a slight twist making it rigid.

A mig introduces less heat into the panel, but the tig leaves almost no weld bead and also easier to metal finish. Time savings depend on how far you plan to make the metal work. Slapping it with mud then mig would be the route. But if you wanted to metal finish the joint with no to very little filler then tig is the route because its easier to accomplish with.

If you plan on hammering the joint then you WILL NEED to grind the weld bead down if you go with the MIG welder. You can not hammer on the weld bead without grinding, unlike a TIG or gas joint.

By the way that welding wire, although some very cool stuff is NOT meant for your purpose. It is not meant for a structual joint like patch panels. Many new car makers use this type of rod on the roof and quarter panel seems just like GM used lead back in the 70's.

When welding a patch panel in I tape a piece of copper tubing that I cut down the middle and flatten out to the back side of the seam that I'm welding and it asorb all the heat so theres no warpage butt welding is the best way IMO.

Thanks for the advice! I want to get good at doing this sort of repair so I’m definitely going to metal finish it and see how strait I can get it without any filler. I'm still a little unsure of the best way to cut to get a precise fit? Was reading bout someone using offset sheet metal shears? Other options would be body saw or grinder with super thin cut off wheel. On more thing, what would be the best way to address where the horizontal line and vertical line meet... just a square corner... or?

Just jump around making little takes until they are all connected so the metal gets to cool off.I believe JW Harris makes some type of mig wire that is a bit softer.I am also a big fan of the copper behind the metal.You can make the parts out of posterboard and transfer them to the metal so you will just have to do some minor tweaking for the final fit.

A rounded off corner will yield less warpage then a 90 degree edge.
The 90 degree corner will concentrate the heat.

The best way to get a tight no gap is get the panels close then file them down til they fit with no gap. A cut off wheel will not make for a no gap joint. Tinsnips is another good tool.

Yes copper behind the joint is a good tool, but it doesn't cure the warpage you will STILL need to address the shrinking afterwords. In case you didn't know but welding causes the metal to shrink to decrease its surface area.
When you weld and get warpage the ONLY and ONLY damage or warpage is the weld seem, that big ole oil can 4" from the weld seem is NOT damage. Fix the damage caused from the shrinking right at the weld seem and that oil can will disappear.
You ONLY work the HAZ area or Heat Affected Zone, this area is the metal that has been turned blue from the heat. The metal in is blue area or HAZ area is the ONLY warped metal so ONLY work this metal, nothing else needs to be worked only the HAZ.

If you are going to use a Tig, the rod they are talking about is called Everdur. This rod is great for panel repair ,low distortion and flows real well. Try this rod you will love it.

I have a question about the hammer welding, with gas welding the heat zone your talking about stays hot long enough to do the hammer and dolly work. But with tig on sheetmetal, and the amps turned down wouldn't the heat zone cool off too fast to work? Or is working the metal at the weld zone not temp. dependant? Guess I need to get that metal working book.

In the old days they gas welded and did the hammer weld while the metal was red-this did two things: it flattened out the weld bead and also provided some stretch during the cool to compensate for the natural shrinkage that occurs. Workers that had the right skills could then metal finish the area with little problem. Working an some of the cars built in the 20's, 30's and 40's you can see some good examples of what this proceedure produced.
Eric's proceedure of hammering the HAZ after cool down is also to introduce some stretch into the area where the shrinkage occured to bring the metal back to it's normal shape and tension. With Mig and Tig the cool down happens too fast to do any hammer welding while hot so you're left with two choices: heat the area up with a torch and hammer weld or just work it cold in the HAZ area.

thanks badbob71, that makes sense.

Finally getting back to my project... And few more questions: What do I do where I don’t have room to hammer the patch from behind? Would it be the same to put the dolly behind and hammer from the outside? One other thing got a dimple right above my cut line that is creating a "oil can" effect. Should I try to address this before I start tacking the panel in? or tack the panel in and the mess with the area when my tacks reach it? As far as the dent can’t get behind it to hammer it out. I have a torch but not to savvy on heat shrinking. How would I go about heat shrinking it?

if dent is not on body line, torch in a circle, outside in and cool with a rag and metal file

ttt

What if it is on the body line?

Here's a 1000 words:

http://i39.photobucket.com/albums/e180/bullage/64/IMG_2179.jpg
http://i39.photobucket.com/albums/e180/bullage/64/IMG_2180.jpg
http://i39.photobucket.com/albums/e180/bullage/64/IMG_2181.jpg
http://i39.photobucket.com/albums/e180/bullage/64/IMG_2182.jpg
http://i39.photobucket.com/albums/e180/bullage/64/IMG_2177.jpg
http://i39.photobucket.com/albums/e180/bullage/64/IMG_2176.jpg
http://i39.photobucket.com/albums/e180/bullage/64/IMG_2175.jpg

Watched a bunch of Eric's videos and made some progress but am still having some "oil can" trouble. The main problem seems to be the body line area in the box. The circle is a small dent and the line is where it is popping out.

I looked at your pictures and honestly why not use a full quarter skin rather then the wheel well patch you are using?
It would save a TON OF WORK. One thing Ive learned is that biting the bullet many times turns out to the best, fastest and easiest method, I helieve this would be one of those times, JMHO.
Think about it, more then likely you would have had your new quarter installed rather then fighting dents just so you can install a patch.

Your quarter will have a big ole shrunken area right above the wheel well when you weld that patch in.

Your quarter is littered with dents all that metal is displaced and causing your problems with the body line popping out.
To remove them you need to use a dolly and hammer, place the dolly underneath or behind the lowspot and hit it with the hammer. This will stretch the metal out making it grow outward or rise up.

You need to correct the dents first BEFORE you weld anything otherwise you are gonna have a bigger mess then you have now.

To test your oilcan to see if its related to shrunken metal or stretched metal is take a small torch or propane torch and heat a small spot of the oilcan. If the dent disappears its because of stretched metal, the dent gets worse you have an oilcan caused by shrunk metal.

Stretced metal oilcans are corrected by heat shrinking with a shrinking disc or torch, but a torch on a large flat panel, well that could turn into a HUGE NIGHTMARE real quick!!!
Shrunken metal oilcans are fixed by using the hammer ON dolly method to stretch the metal back out.

You read my mind about just installing a new quarter patch. If I could see into the future I’d be done by now. As far as for why I started with the patch; I was able to cut the quarter off of a buddy’s 4 dr on its way to the wrecker (so free of charge.) Second my frigerator magnet didn’t catch the skim coat of filler so to my disgust when I stripped the quarter nothing but head aches. So throw the last 10hrs of work out the window and on to plan B.
1. Which is the best manufacture to go with? Aren’t the “skins” a thinner gauge?
2. Even if I go with a skin I’ll have even a longer seam to weld so won’t I still be dealing with the shrinking issues? Or if I cut right next to the bend/top body line like I’ve seen most of them installed will shrinkage be less of an issue?

Thanks again for your help and great videos

You read my mind about just installing a new quarter patch. If I could see into the future I’d be done by now. As far as for why I started with the patch; I was able to cut the quarter off of a buddy’s 4 dr on its way to the wrecker (so free of charge.) Second my frigerator magnet didn’t catch the skim coat of filler so to my disgust when I stripped the quarter nothing but head aches. So throw the last 10hrs of work out the window and on to plan B.
1. Which is the best manufacture to go with? Aren’t the “skins” a thinner gauge?
2. Even if I go with a skin I’ll have even a longer seam to weld so won’t I still be dealing with the shrinking issues? Or if I cut right next to the bend/top body line like I’ve seen most of them installed will shrinkage be less of an issue?

Thanks again for your help and great videos

Take that 10hrs spent as a learning tool.
Sometimes its best to know when to walk away and start over fresh versus fighting your own mistakes or problems that shouldn't be in the equation in the first place.

Yes when you weld that new skin on you will still have warpage. But the difference is your current route of that patch has a HUGE amount of welding to be done in a small confined area. That warpage will be a huge localized oil can right behind an area you don't have great access so you can correct the warpage.

Doing the skin the warpage is not localized, not welded into prior damage, also at a location you can get behind and work the seem so you are able to remove the warpage.

sevt - im a little confused. i thought heating metal causes it to grow, ie stretch. so if i had an oil can caused by shrinkage, heating it would cause it to go away. you stated it the other way??? could you explain?



"To test your oilcan to see if its related to shrunken metal or stretched metal is take a small torch or propane torch and heat a small spot of the oilcan. If the dent disappears its because of stretched metal, the dent gets worse you have an oilcan caused by shrunk metal."

You are right heating metal causes it to expand, but that expanding metal is held in place by surrounding the metal which is cool and stronger. That metal cant expand outward so it grows upward, now the shrinking occurs when the metal cools. Because you now have all these extra metal molecules trapped, when the area cools the metal shrinks down into it self.

Its the heating and cooling cycle that makes metal shrink. This is why welding creates an oilcan. The metal is heated and cooled causing shrinkage to occur at the weld.
Welding shrinks metal it does not stretch it...Eric

So do it something like this http://www.chevelles.com/showroom/uploads/1259/rightskin.jpg?
It looks like a lot more welding/heat? And the area in the front will be hard to get a dolly behind.
Anybody got any good suggestions on which skin to go with??

thats actually 7000 words

So do it something like this http://www.chevelles.com/showroom/uploads/1259/rightskin.jpg?
It looks like a lot more welding/heat? And the area in the front will be hard to get a dolly behind.
Anybody got any good suggestions on which skin to go with??

yes thats how I would do it. Yes more then likely you will have more feet of welding but your welding will not be localized in one spot, also you wont be welding into prior damage.

To gain access to the back after welding to correct the warpage cut a small hole in the outer wheel well so you can get your hand behind the seem. Because the wheel well has a great deal of compound curve your warpage will be darn near nothing when you weld your access hole shut.

I think what most novices don't realize is that if you are going to use a patch panel/skin etc. to fix a rusted area you should try and keep the weld seam as close to a bend/body line in the sheet metal as possible.The sheet metal is very flexable when just flat but when you put a slight crease in it it becomes extremely stiff. The stiffness will stop a lot of warpage when welding provided the heat is restricted as much as possible. Just try taking a small flat piece of sheet metal say 6" x 2" and see how flexible it is when flat. Now put it in a vise along the 6" length. Bend a slight angle, 3 or 4 degrees, the full length of it. Now see how stiff it is. Back in the early 70's we used oxy acetylene torches and brazing rod to put on panels. You had to get the metal red hot to make the bronze rod stick. With a small torch and a low flame you could work along a body line, a bit at a time, and keep the panel from warping very much. You just have to take your time and stay close to a body line. It might mean a bigger patch panel but you won't have to weld across a large flat area. With the MIG welders we have now the welding is easier but the same rules apply. If you put in too much heat it will warp. Don't be in a hurry to get it done.

And the area in the front will be hard to get a dolly behind.
Anybody got any good suggestions on which skin to go with??

Easy cut an access hole in the outer wheel well. This way you can reach the entire weld seem with a dolly.
Welding the hole back shut will yield little warpage due to the high compound curve in the wheel well.

Also by working the seem after welding you can remove the warpage making for a filler free repair if you so desired.