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TR2/3/3A Floor pans.

sp53

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Floor pans. I am putting floor pans in the passenger side of pre60K and was looking for tips. The part I am struggling with now is the area next to the drive line tunnel. I have cut the welds on the vertical part of the pan where it meets the tunnel, but the drive tunnel is evidently spot weld also to the flat part of floor pan itself where the right angle turns back under. What have other done here? I have got the floor pan free from the outrigger and at the front under the dash, but I do not want damage the driveline tunnel.
 
I cleaned the top surface area well with a wire brush mounted on an drill so I could see the spot welds. Then I drilled the spot welds out
Charley
 
We think alike charley that is basically what I was doing. I will clean the area better and get some better light on it.
 
I drilled a mess of spot welds out when restoring my TR, and the best tool I found for that purpose was a 3/16", or sometimes a 1/4" stub 135 degree cobalt split point drill. The split point keeps it centered and the stub allows greater control. Cobalt 'cause it works better then high speed on the welds.
 
I drilled a mess of spot welds out when restoring my TR, and the best tool I found for that purpose was a 3/16", or sometimes a 1/4" stub 135 degree cobalt split point drill. The split point keeps it centered and the stub allows greater control. Cobalt 'cause it works better then high speed on the welds.

I'm also changing a floor out. I didn't know about that drill bit. I'm going to get one.:encouragement:
 
Let me know where you find one in Canada Karl please.

I can tell you that the Princess Auto Spot Weld drill bits don't work at all....

Cheers
Tush
 
I had bought a spot weld cutter, but it's not necessary on these cars, and makes a gigantic hole. If you drill out with just a regular metal drill bit, then you can actually use the holes you end up with and fill them easily with the MIG when you put in your new panel. Expect to go through a ton of these, I probably wasted 15-20 of the cheap ones, and you can get more life out of them by giving it a shot every few seconds with WD40. Heat is your enemy when drilling and the wd40 will cool it.

If you have full replacement panels that don't need cutting, a cheap pinch spot welder from Harbor Freight is a worthwhile investment. I definitely got my money's worth out of mine.
 
I'm also changing a floor out. I didn't know about that drill bit. I'm going to get one.:encouragement:

Well, get more then one. I went through about a half a dozen when I restored my car. They aren't that expensive. That included two floor pans, outer rockers and boot pan. That's where the cobalt works better then the high speed, they don't wear out as fast. Also keep the speed of the drill down. I never had to use any lube by going slowly.


McMaster has the 3/16" short cobalts for less the $3.00 apiece. The 1/4" for about a buck more. Get some of both sizes. I found most of the spot welds small enough to use the 3/16" drill, but some I needed the 1/4". I suppose you could get away with the the 1/4". I also didn't drill all the way through both panels. Just enough to release the panel I was removing. That's where the 135 degree point helps out. Sometimes you might need a bit of chisel persuasion to knock it all the way off if you have a stubborn one.

https://www.mcmaster.com/#standard-drill-bits/=wmw0dm

I also tried a "spot weld remover bit", and although it would release the outer panel, you were left with a round section of panel (the welded part) still stuck to the inner panel. That requires grinding it off to level it down. Too much work.
 
Unfortunately, mcmaster doesn't deliver to Canada....

We will see if Karl comes up with something locally.

Cheers
Tush
 
I used a titanium coated DeWalt bit and still have it--useable.
Charley
 
I drilled a whole lotta spot welds. But, my primary weld breaker was a 1" wood chisel. Once between the metal sheets it splits the welds promptly. Of course I started with one 4 " long and it ended up 1" long after all the sharpenings. It has to stay sharp to work, so you end up at the grinding wheel every 5 minutes or so.
 
Ditto on drill bits rather than spot weld cutters. I can't count how many bits I used for all my rust repair. I think the rust tends to dull the bits rapidly too. You should be able to run some sandpaper or a die grinder over the panel and you'll see little depressions where each spot weld it located. After drilling (and I didn't drill all the way through), I would use a panel splitter to split the two panels. It worked great, after drilling the welds and weakening the bond. It really was a handy tool.

https://www.amazon.com/Steck-Manufacturing-20015-Buster-Chisel/dp/B000JFJMJ6

pat
 
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