#21
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James, is cutting out the patch and redoing it an option?
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Steve ærugo nunquam dormit |
#22
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Possibly. But I might be wrong about it and find myself in the same place.
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James |
#23
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I might just give it a try. I think the patch is slightly thicker than the metal around it. I Shaped a curve in it side to side, but not top to bottom. If I patched it again, I would radius the corners and try to shape it the same shape as where it is going. Also minimal gaps. This may not be my problem but it’s worth a try.
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James |
#24
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If you do re-do it try getting the metal the same thickness. That is pretty important if you are trying to get it close in metal. That era VW should probably be 20 gauge. (.036 or thereabouts)
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Chris (trying to be the best me I can be) Last edited by Chris_Hamilton; 07-25-2018 at 07:52 PM. |
#25
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I actually have a piece of original metal from another repair, I used to bin that stuff but now I keep it in my tetanus bucket with scraps from practicing different things, Someone actually mentioned the importance of matching metal thickness in a previous post but I had already welded it in. I am hoping that is the problem, but I have been going round and round and seem to be doing the same things always coming back to not being able to get that patch to line up with the shape of the rest of the panel. I get the panel close but can't quite get rid of the oil pan, try everything to get the patch to line up but it won't, shrink a little here and there and the oil can goes away but the crown flattens out with the patch area being the lowest and the flattest.
I am just too obsessive and stubborn to give up. I hate not being able to figure something out. I think I can shrink and stretch well enough for what I am trying to do and can see the shape it should be and where it's not right. If I can figure this out, the next job will be that much easier.
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James |
#26
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Quote:
Some of us obsessive and stubborn guys learn that panel metal is non-trivial, in thickness, hardness .... and alloy. On one level, grab a chunk of whatever and glom it in and whack it around and go for the spackle. On another level, thickness and gaps matter, with rounded corners - or even round patches. Still again, minute attention to weld speed and depostion rates, tacking and hot working can matter. Ultimately, using "factory" metal of the era and fusion welding can make things go very smoothly. I used to work in a resto shop where we would see 10 - 30 cars a year, vintages from 1910 to 1950. We 5 metal men got to prefer certain factory steels - some liked GM, some liked Auburn/Cord, and I preferred Chrysler - and aluminum.
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Kent http://www.tinmantech.com "All it takes is a little practical experience to blow the he!! out of a perfectly good theory." --- Lloyd Rosenquist, charter member AWS, 1919. |
#27
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Quote:
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James |
#28
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Quote:
Keep asking those questions, James. Sometimes we can get the question just perfectly - and other times we have to just peck away at asking .... Keep practicing ... and try new stuff.
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Kent http://www.tinmantech.com "All it takes is a little practical experience to blow the he!! out of a perfectly good theory." --- Lloyd Rosenquist, charter member AWS, 1919. |
#29
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I stretched out the patched area a lot because it was always staying low. I did this on purpose just to see if that was really the problem. It’s now a small tight bulge with lots of tension in it but the rest of the panel is taught and holding its shape. I guess the trick now is to shrink it just enough...then even out the rest of the panel. I have tried spreading it out off dolly but I think it is stretched to much in a small spot to even it out without heat shrinking. Feels like progress...
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James |
#30
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Quote:
Pinpoint shrinks are done with a sharp, hot (oxidizing) flame. Point the torch flame straight down (90deg to panel) and with the inner cone a nickel's thickness away. Count one-two, and pull flame off and hit the metal with the flat-faced hammer. (Hold the hammer and torch with the same hand - the torch won't mind the bouncy ride, if the pressure is right.) Back your work with a 2" thick block of wood, about a 4" X 4" face. This avoids stretching, and adds a romantic aroma to the shop. Remember that the metal keeps shrinking until it is ALL the same ambient temp. I have measured for this, many times. Hammer until the metal is only warm to the touch - then wipe with a wet rag - no hissing allowed, just steam.
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Kent http://www.tinmantech.com "All it takes is a little practical experience to blow the he!! out of a perfectly good theory." --- Lloyd Rosenquist, charter member AWS, 1919. |
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