Printable Version of Topic

Posted by: rick 918-S Jun 14 2013, 09:01 PM

This is the method I use to split spot welds. Some guys use the Blair spot weld drills. I have nothing against them but when I had my shop I found that my employees had no concern for the cost of the bits or the way they were using them. They would break the hardened cutters and toss them like a used rubber on prom night or they would over drill and end up weakening the attachment for the new panel.


If used correctly the Blair is a nice tool. The proper use is to use the cutter to score the sacrificial panel then use a air chisel or a hand chisel to split the panel. Nobody uses it that way. At least no one I've ever had the experience of seeing use the tool.

So, I imposed this method in my shop and would spot check the results to be sure my guys were doing it correctly.

This is my way not the only way.

First I trim away as much of the panel as I can and usually try to leave only the spot weld strip.

Run a grinder over the spot weld strip to show the spot welds.





Then I use a 3" grinder and grind the spot welds. My goal is to thin the metal not grind through.



Here is what it looks like after I grind.



I like to use a screw driver that I have sharpened to a chisel end. I work it in and around the spot welds until I get it split.



Here is what is left after I split the spots. Notice the actual spot welds are still showing on the body.





After grinding and prepping the body for the replacement panel.



This is not the fastest way but this is how I prevent damaging the car and weakening the metal I want to re-use on the body.

Posted by: Cairo94507 Jun 15 2013, 06:22 AM

Wow that is a very nice work. Hard to find shops that will go the extra mile these days to preserve the original metal in the best possible condition.

Posted by: TargaToy Jun 15 2013, 06:54 AM

Rick, Thank you! ...as always...

Posted by: Racer Chris Jun 15 2013, 07:02 AM

Very well demonstrated Rick!

Posted by: bulitt Jun 15 2013, 05:44 PM

"Hate" is an awful strong word. I hate spot welds!
So you must be using an actual spotwelder to reattach panels?
I think If I was doing major panel work I would invest in one.

Posted by: ConeDodger Jun 15 2013, 05:53 PM

I actually use the spot weld drill bits. They are about $15-$18 each so Rick is right, abusing them is stupid. It takes a fine touch with the drill to use them properly. Go too deep and you have a hole where you will want metal for the new panel...

Posted by: r_towle Jun 15 2013, 08:33 PM

Blah blah blah

I would have learned more if the was not the Benz...

Posted by: rick 918-S Jun 15 2013, 09:16 PM

No you don't have to use a panel spotter to reinstall the panels. I have one but depending on what I'm working on I will either mig, tig, or spot weld.

How this whole discussion got started is when tomeric914 posted this thread

http://www.914world.com/bbs2/index.php?showtopic=211105

And was posting about using the Blair spot weld drill to remove panels. So this is the thread I stated I would post. Now welding is a whole nuther thread...

Posted by: rick 918-S Jun 15 2013, 09:18 PM

I gotsa finish this thing some day!

Posted by: stateofidleness Jun 16 2013, 11:45 AM

Rick,
Thanks for posting!

I'm toying with the idea of replacing the rear pans on mine after removing the tar coating and finding more rust than I thought... When looking at the underside of the car, it appears the whole floor was one piece?

I've seen the repro pans for sale and was wondering what is the best way to remove the exisiting pans cleanly in preparation for the new pans? How should it be cut properly to separate it from the "front" pans underneath the middle crossmember thing?

Posted by: rick 918-S Jun 16 2013, 03:31 PM

I look at the pan in the car and try to leave what I can of the original one. However you usually end up using the whole repair panel because where the original pan is welded to the longs it's usually rusty enough to merit just changing it. Some day maybe I can do a pan replacement how-to.