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  #21  
Old 12-26-2017, 12:00 PM
Aluminum Aluminum is offline
 
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Quote:
Originally Posted by wirejock View Post
For the future, consider using a Vixen file to clean up long straight edges like skins. Much faster and safer. Two or three passes takes out the shear marks.
After removing shear marks with a vixen file, consider using this edge deburring tool to break the edges. Much faster than filing/sanding.
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  #22  
Old 12-28-2017, 11:02 AM
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Draker Draker is offline
 
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UPDATE:

In case anyone's curious, I put a little elbow grease and a metal shrinker into the skin and had the below results (bent skin on top, straight one below for comparison):





Much better, but at the end of the day, I will be re-ordering the skin anyway. I'm not happy with the score marks that the shrinker tool leaves, which as Scott pointed out may lead to cracks eventually.

Thanks very much for everyone's advice and best wishes for the new year!
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  #23  
Old 12-28-2017, 12:12 PM
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az_gila az_gila is offline
 
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Quote:
Originally Posted by Draker View Post
...

I'm not happy with the score marks that the shrinker tool leaves, which as Scott pointed out may lead to cracks eventually.

...
Just for kicks, try polishing out all of the score marks with Scochbrite and measure the resulting metal thickness.

The results will be interesting for all of us.
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  #24  
Old 12-28-2017, 01:10 PM
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Sam Buchanan Sam Buchanan is offline
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Quote:
Originally Posted by az_gila View Post
Just for kicks, try polishing out all of the score marks with Scochbrite and measure the resulting metal thickness.

The results will be interesting for all of us.
I agree, I would try polishing out those marks before committing to a new skin. Your repair looks quite good, it will ride on top of the anti-scuff tape of the flap.
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  #25  
Old 12-28-2017, 01:37 PM
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I would have no problem using it but I wouldn't thin the metal by fully polishing out the marks....
There is minimal localized loading of the skin at that point so the likelihood of future cracking is quite remote (just make sure the very edge of the skin is polished well). In fact it might be more likely if you thin the material excessively.

In my opinion a better fix would be to sand flat (just enough to assure there is nothing raised above the normal skin surface with 220 and then use a small amount of filler applied with a razor blade to fill what amount of groves is left. Sand the filler flush. Once a bit of filler primer is applied and block sanded it would probably be undetectable.
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  #26  
Old 12-28-2017, 01:56 PM
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az_gila az_gila is offline
 
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Quote:
Originally Posted by rvbuilder2002 View Post
I would have no problem using it but I wouldn't thin the metal by fully polishing out the marks....
There is minimal localized loading of the skin at that point so the likelihood of future cracking is quite remote (just make sure the very edge of the skin is polished well). In fact it might be more likely if you thin the material excessively.

In my opinion a better fix would be to sand flat (just enough to assure there is nothing raised above the normal skin surface with 220 and then use a small amount of filler applied with a razor blade to fill what amount of groves is left. Sand the filler flush. Once a bit of filler primer is applied and block sanded it would probably be undetectable.
Ken, I agree, but the OP has already ordered a new skin, so removing all of the marks and thinning the skin in the process would give us all data on how much shrinking a skin can do to it's thickness.

It sounds like the skin in the picture has now been declared scrap.
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  #27  
Old 12-28-2017, 02:25 PM
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After some scuffing and polishing, with most of the score marks gone, I'm down to 0.0275" at the thinnest part of the sheet.

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  #28  
Old 12-28-2017, 03:49 PM
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Build on! A bit of glazing compound prior to paint and you are good.
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  #29  
Old 12-28-2017, 05:29 PM
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az_gila az_gila is offline
 
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Quote:
Originally Posted by Draker View Post
After some scuffing and polishing, with most of the score marks gone, I'm down to 0.0275" at the thinnest part of the sheet.

Interesting, since if you take away the 11% thickness (5.5% per side) of the low strength pure aluminum Alclad layer you are left with 0.0285" of the higher strength aluminum.

I presume both sides were sanded/polished approx. the same amount.
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  #30  
Old 12-29-2017, 07:09 AM
pa38112 pa38112 is offline
 
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Nice job with the repair!
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