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Removing dent from tube cage

A friend graciously loaned me his VTA-mod ST70 and I put a thumb in the wrong place and dented its tube cage. As you can see it's not a big dent, and I think I can get it out, but I imagine there are better and worse ways to do it. Heat gun? Gorilla tape?

Larry Fisher
Port Townsend WA
 

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Set it dented side down on a hard surface, and tap the dented area on the inside surface with a rubber hammer.
A few taps in the right place will fix it. Be gentle and check after each tap, since it's near the welded-on side.
If you tap too hard, there will be a vertical crease near the side edge.
 
That will definitely help. Avoid the bent-over bottom edge of the cage, though.
You don't want to flatten that.

Don't over tap, as the cage will then bend outward, due to the thickness of the welded-on side.
Ideally there should be a 1/16" piece of metal under the perf part of the cage (not under the solid side's edge)
when tapping. That, and a piece of wood on the inside perf surface, will make it nice and flat.
 
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Dry ice can work sometimes. Put the ice on the dented area and the cold shrinks the metal back to straight. It usually stays after it comes back to room temp. Remember, the dent is actually stretched metal and the extreme cold shrinks it back to the shortest path between the more rigid ends. It also works on car dents!