Friday, December 9, 2011

Wish that dent away...

One of the most difficult aspects of a old restoration project is what to do with BIG dents...now I'm not talking about those pesky little dings you get from a rock popping up and ringing your tube, but those large, tube destroying depressions that make you want to cry, take the bike apart, and hang the frame on the wall.

Unfortunately, these are tough to work with, normally requiring you to replace the entire tube.  But for folks who want to keep the frame as original as possible, we need to get creative.  FA small ding can be filled with some silver, filed down, and is ready to go.  Filling these with silver would cost you about 15 bucks in product and a lot of heat...so much so that you might as well replace the tube.  But, if you have a way to pull the dent back out, you have a chance to save the frame.

So here is the project bike...a yo with a nasty dent in the top tube from an automobile vs. bike accident.

And the slide hammer/puller I made...

It's a simple tool that uses a stainless 1/2" rod, #0 chuck, and an 1 1/4" stainless solid bar stock.  A little time on the lathe, welding table, a sprinkle of creativity and we have a dent puller for thin wall bicycle tubing.

We'll start by tacking on a piece of stainless wire...

We'll attach the puller, tighten down the chuck and work the dent from the middle and out each side to bring the edges up.  You can see here where I attached in three places and left just the small tack marks behind.
What's left after using the slide hammer is a small detent we can now fill with silver and feather out to the edges.  Add a little heat and some 45% silver...
Wha-la, another original tube saved...
Cheers,

rody

1 comment:

Edoz said...

I've done that same thing at work. If it's good enough for aircraft parts, it's good enough for bike frames:)