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JeffL
12-24-2006, 12:59 PM
Hello, I was put on to this site from a fellow VW owner. He thought someone here might be able to help me.

I want to weld a period sunroof frame into my 56 VW Karmann Ghia.

I have used a spot welder similar to a Lenco unit with separate electrode cables (not the standard "C clamp" spot welder). A friend had one and I used it for many of my VW Kamann Ghia panels.

The Ghia metal thickness is .039 inches and the sunroof frame is almost twice as thick at .071 inches. Total thickness of .11 inches (almost 1/8 inch). I have seen the "C clamp" style units but they don't seem to claim enough metal thickness to spot weld my application.

Does anyone have a recomendation on how to spot weld this correctly? When I roll over the edge of the roof opening there is not much material to use a plug weld. I think I would burn away the outer skin.

http://karmannghias.org/Webasto/framestrip2.jpg

Phil V
12-24-2006, 01:30 PM
If you cranked up the timer dial on the Lenco it should be able to weld metal that thick. try it on a couple test pieces first to make sure but it should work.

JeffL
12-24-2006, 01:43 PM
If you cranked up the timer dial on the Lenco it should be able to weld metal that thick. try it on a couple test pieces first to make sure but it should work.

Since I moved, I don't have access to the Lenco style unit anymore. I'm trying to see if there are other alternatives. Your post suggests, however, that I need the power of a Lenco unit and that the "C clamp" styles won't cut it.

Phil V
12-24-2006, 04:41 PM
There are industrial rated "C" clamp style spot welders that would have more than enough power to spot weld the panels that you want welded but those would not be the normal 110V or light duty 220V welders. Not only that but how would you spot weld that roof panel in with the "C" clamp type welder ?

There are industrial rated bodyshop type spot welders that come with many different shapes and sizes of welding tongs and the actual spot welder/tongs are suspended by a cable to make them more managable. Those kind of bodyshop type spot welders are big bucks, many thousands of dollars.

MARTINSR
12-24-2006, 05:29 PM
The Prospot PR10 that we have where I work would do it no problem (C TYPE) STRSW.

Doing that test as Phil suggests is ALWAYS the best way to go. Do a test and a destruction test to see how it held up.

Do a small test on MIG welding it as well. Try drilling an 1/8" hole thru both panels. Weld up that hole with the MIG hitting the wire down at an angle to the lower layer of metal. You could be surprised how small you can keep a perfect little weld with this technique.

Brian

JeffL
12-29-2006, 10:18 PM
Thanks for the tips.

I spent some time over the holiday at some shops and they recommend trying to rent one of the large separate cable units for this job before spending $1k on a Lenco unit.

If I can't rent one, I will try some more work with my mig welder. Thanks

Phil V
12-30-2006, 12:39 AM
Jeff, what state are you in ? Anywhere near S. Michigan about 40 miles west of Detroit ? If you are close enough I'd let you use my Lenco-Spot to finish up your Ghia roof.

JeffL
12-30-2006, 11:09 PM
Jeff, what state are you in ? Anywhere near S. Michigan about 40 miles west of Detroit ? If you are close enough I'd let you use my Lenco-Spot to finish up your Ghia roof.

Phil, thanks for the offer, that is really nice of you. I'm in Bowling Green, KY so I'm a little far away (of course I just drove 600 miles to PA over the holiday). Your Lenco I'm sure is the right tool!

Here are some more pics of the damage today. 4 hours of measuring, 2 glasses of wine at dinner, and then 15 minutes of cutting. The metal still needs final trimming but it all fits! I have it blocked up to do the final trimming.

http://karmannghias.org/Webasto/Open1.JPG
http://karmannghias.org/Webasto/Open4.JPG

JeffL
01-03-2007, 07:49 PM
Thanks for the input, I decided to use my mig welder and things went fine. I used .030 wire and ran the unit pretty hot to get the penetration into the frame below the sheet metal.

Here is a link to some of the pictures of the installation and a picture.

http://karmannghias.org/Webasto.htm
http://karmannghias.org/Webasto/Webastoroofin3.JPG