#21  
Old 09-10-2019, 08:13 PM
tjs72lemans tjs72lemans is offline
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Weld thru primer. It will stay on when the heat from your welding is done. Regular primer will burn off.

  #22  
Old 09-11-2019, 12:14 AM
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Greg Reid Greg Reid is offline
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The thing about weld through primer is that is supposed to be removed before painting. If you plug weld, it is supposed to be removed from the weld points. Honestly, it doesn't seem to be good for much except that it protects the interior surfaces of an overlap from future corrosion. Seems that way to me anyhow...

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  #23  
Old 09-11-2019, 01:39 PM
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Sounds like I should use epoxy to paint the fender, but mask off the weld joints. Then use weld-thru primer only under the "foot" of the brace that attaches to the bottom edge of the fender. That's an overlap area right next to a weld, that I can't paint later.

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  #24  
Old 09-11-2019, 08:14 PM
tjs72lemans tjs72lemans is offline
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What should I paint the backside of the patch with, before I weld in the inner brace? Something needs to protect the bare steel, but not sure what?

The thing about weld through primer is that is supposed to be removed before painting. If you plug weld, it is supposed to be removed from the weld points. Honestly, it doesn't seem to be good for much except that it protects the interior surfaces of an overlap from future corrosion

That's why I mentioned weld thru primer. It's good for areas that need some bare metal protection that will stay there when your done welding and can't get to it afterwards to paint.

  #25  
Old 09-12-2019, 11:43 AM
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I'd epoxy it. Also you can epoxy any part of the fender and scrape off the primer where you will plug weld the fender to the brace with a scribe or some such tool like that. Weld thru primer is zinc based, and makes nasty fumes.

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  #26  
Old 09-12-2019, 06:56 PM
flat-bill flat-bill is offline
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Rather than weld the bracket on and just ask for more rust you might consider gluing it on with 3M 8115 panel bond adhesive. It has unbelievable strength if used correctly. If you use it to completely seal the area where the 2 pieces are joined that should be not rust. Billk

  #27  
Old 09-12-2019, 08:03 PM
tjs72lemans tjs72lemans is offline
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No reason to epoxy something before hand that will burn off later. That's why they make weld thru primer. Once welding is done, you can finish what you can with epoxy. That's what I do.

  #28  
Old 09-14-2019, 01:12 PM
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Not in a high rot prone area like behind the fender brace. Zinc melt point is way lower than steel and the weld definitely burns through.

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1962 Catalina convertible, Starlight black w maroon interior & white top.
  #29  
Old 09-23-2019, 12:11 PM
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I'm almost ready to strip and prime this fender. Is it OK to sandblast the headlight bucket area to strip the old paint and primer? How do you guys strip off old undercoating?

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  #30  
Old 09-23-2019, 10:10 PM
MUSLCAH MUSLCAH is offline
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Yup....blast away....undercoating with rice cakes....or heat gun and scraper

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