Cutting spot welds, gotta start somewhere :) Options

[bryanthompson]

I started on my 914 project and decided to do the trunk first. So, i started chipping away bondo from the inside of the bottom of the trunk and found (suprise!) more rust than expected. So, the bottom part of my trunk pan has to be replaced.

Anyway, i bought a spot weld cutter yesterday, but something about it makes me wonder. The tool looks just like this:
(IMG:http://www.ingallseng.com/graphics/Prodcut_Pictures/92900.jpg)
So, should i trim down the spikey thing or let it go through the whole car? I realize i'll be welding it back up so it wouldn't be the worst thing in the world if it made a hole, but what i'm worried about is the bending effect putting that much force will have... like i'll end up with little pimples around the hole left by the spike (not the saw part).
(IMG:style_emoticons/default/smash.gif) (IMG:style_emoticons/default/sawzall-smiley.gif) (IMG:style_emoticons/default/welder.gif) (IMG:style_emoticons/default/monkeydance.gif)

[Slowpoke]

Those tools are handy. I just drill a hole in the panel the size of the spike coming out of it. This gives me better control of the cutting and a small 1/8 hole is easy to mig close on the piece I'm trying to save. But, you do have to be carefull not to cut all the way thru both pieces of metal. Because, you are defeating the purpose of the stop feature (that's why the spike it there, you adjust the stop from the other end of the tool). I also have luck just drilling with a drill bit the spot weld itself. All it takes is patience either way.

[bryanthompson]

Ohh, i see now! I didn't even notice the hole on the other end of the tool was shaped like an allen head. well, shoot, i'm gonna go play now! Thanks man. (IMG:style_emoticons/default/beerchug.gif)

[Bleyseng]

(IMG:style_emoticons/default/agree.gif)

Just go slow and don't push too hard so that the bit does the work by cutting only thru the top layer of the panels. I use a drill set first to then locate the spot weld cutting bit so it doesn't wander all over the place.

Geoff

[kafermeister]

Hmmm. I've got one of those and the spikey part in the middle is spring-loaded. No need to drill a hole. Mine wonders all over the place even with a pilot divot. I think the one you have may be better than mine. Hope yours works better.

Rick

[bryanthompson]

Just go slow and don't push too hard so that the bit does the work by cutting only thru the top layer of the panels.

after some practice, i got it... but I went through a couple times. Will be good practice in fixing holes in sheet metal though.

And, it turns out the center was spring loaded, so I drilled a small hole in the middle of the weld, not all the way through, just tapped the surface. Anyhow, going slow it seemed to work fine. Once i get it all looking decent i'll take pics... looks sortof crappy right now.

[qa1142]

If you work slowly, you can just pop the spot welds with an air chisel. Way faster than drilling every weld, just make sure is you sacrifice metal it is the piece you are replacing. I had rest pf battery tray out in (IMG:style_emoticons/default/sawzall-smiley.gif)