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Discussion Starter #1
I got my patch panels in for my '49 Chevy Truck cab. I am patching the cab corners and the outer crowl area. I am getting mixed opinions on how to weld them into place. My plan is to use those small interlock clamps that create a .040" gap in the seam to weld up. then grind the weld down smooth. This to me seems the best way to avoid minimum body filler.

One person tells me I cant do it like that you have to over lap the seams. This way sounds like when you grind down the weld you will grind it away plus will have to use more body filler to feather the seam out.

Then there's the butt weld. but again seems you will grind away you weld were it wont hold.

Iam using a Millermatic 135 Mig welder with co2 as my shielding gas. So which method should I use? Is there anther way?

Thanks ! :D
 

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what can be done is you can overlap the patch panel a little bit and use a crimping tool to bend the metal underneith back so that the two pieces are flush
 

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I just used your gap method on my '53 king cab and it worked great. Was my first attempt at MIG on sheet metal and it came out like a pro did it! Actually, I didn't use the gap clamps, just used deep reach vice-grips and eyeballed a gap for a butt weld. Keys to a good job are get the metal very clean, the gap accurate to about 1/32" then just spot weld. NEVER run a bead that generates a visible blue zone bigger than 1/16". Spot an inch apart, then 1/2" then 1/4" and so on 'til the gap is totally filled. I used 3 two pound reels of 0.025" wire and welded about 25 linear feet of butt joint on the pickup and have zero warpage,little filler needed.



[ January 31, 2003: Message edited by: [email protected] ]</p>
 

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Discussion Starter #4
Hey man thats cool looking!!! I have the .025 wire. Those crimping tools are a pain to use around corners. I know my idea would work just needed the reassurance I guess.

:D
 

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I bought one of those vice grip crimping tools from Eastwood. All it did when I tried it on the truck was spring the jaws on the pliers, very little effect on the heavy sheet metal. That is when I decided to go the butt weld route, which I am now very happy with. My guess is that the crimping pliers work great on late model cars with 100 gauge metal foil bodies but forget it on 50's cars with real metal in the body pannels.
 

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Discussion Starter #6
Yep I had the same problem I thought about getting one of the air crimping tools. But with the butt welds with a gap when your done you shouldnt even be able to tell it was patched.
 

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Maverick, The way you described is a great way. I've flanged them in the past and where the panels lap I had holes punched in the outer layer to make plug welds to the lower panel. In between the plug welds were small beads to help hold also. I know this sounds like alot but by skipping around there is less heat at one time to the metal. Yes the plugs will hold if properly done. i've tried this on chop tops and it seemed to work great. :)
 

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Might I make a sugestion maverick?I have many years of welding behind me{far too many!}Go to your welding suplier and get some 75%argon25%Co2 for shielding gas.It costs a little more but it makes a much slicker weld with a LOT less spatter.
 

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Discussion Starter #9
Thanks for the advice Alred. I know it is better but my supplier only has the real tall tanks they wont refill my short co2 tank. Iam dont have a very good shop area for that size of a tank. Plus I own a restaurant and have the co2 tanks readly available for my soda machine. It works pretty good for me.

:D
 

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Buttwelding is the way to go.When you overlap and weld sheetmetal you are setting your self up for rust in the future.Plus the welded area is impossible to shape with hammer and dolly.we use .023 easy grind for wire it grinds easier and the welds are smaller.One thing I have learned the hard way is to grind only the weld bead as much as possible after welding is complete being carefull not to get surrounding metal to thin or it rusts prematurley.
 

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when I patched my front fender I did the overlap method and it came out beautifully although it did take more filler that the bit method it was the best choice for that area (cut a sqare in the metal no way to clamp it and it was still on the car)
 

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There are time to but weld and time to overlap. A good air crimp tool with a hole punch adapter is a great tool. To assist in rust prevention, keep a can of spray weld thru primer handy and always try to seal behind the overlap seam with tar or spray on undercoat material whenever you have access. Willys, I love that truck!!

Trees
 

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Definately do the butt weld. The argon/Co2 mix (sometimes referred to C25) works well. The smaller wire is also easier on sheetmetal. .035" will work, but will put much more heat into the panel. Stick to the .023". Be sure you keep the stitches short and move around to keep the heat from building up. You can also buy a heat absorbing paste to apply on both sides of the weld.(I've never used this) As for grinding, take your time, grind the weld down carefully (across the direction of weld) untill its almost flush to the host metal. You can then use a fiber disc to further blend out the weld. Use the leading edge of a grinding wheel and the flat surface of a soft disc for best results. This should reduce the amount of good metal lost. hope this helps.
 

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I like the overlap method because you have less problem with buring through. If there is any trash in the weld it can blow a hole. If you overlap a bit this is usually less of a problem. What I have done for small panels is cut the piece 1/16 longer and roll down a small edge that just fits under the other piece, but still sets flush.

When butt welding I dont like to leave a gap. If your welder is set properly, it should penetrate deep enough that grinding the weld down will not affect strength. Most of the time I can see weld from the back side of the weld surface even when butting it right together.

I am however just a self taught patch panel man. I just do what works best for me. I would suggest you do the same. Practice on some junk and decide what is easiest for you to get the results you want.

Chris
 

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they have a step tool that aslong as the panel comes to a flat area u can put a step in both panels so the patch is fairly flush and also punch holes into itso most of your wled goes and fills up the hole. but if it is not a flat area there are a cpl different ways to do it cant think of them off the top of my head but if ya email me i should remember them
 

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If you need to use the flange method, there is an air powered tool called a flanger that will put a step into the sheetmetal. I think Campbell Hausfield has one (special order) & it works like an air chisel.(repetitive hits to do the forming.)
 
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