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wolfewiz
Feb-24-2004, 11:37am
I wish I would have read this message board before I did it but oh well, whats done is done. I glued my endpin with superglue. Call me an idiot if you like, but I'm a rookie and need some advice. What should I do now? Can the endpin expand and break the end block? Has anyone ever seen this happen? Should I just wait and see, or is there something more proactive I can do or have done? Any help is greatly appreciated.

Chris Baird
Feb-24-2004, 12:06pm
The endpin probably won't expand as ebony is very stable but the block may swell. I don't think it will split though. If you are really worried about it cut the endpin off flush then drill it out and re ream it for a new endpin minus the glue.

Feb-24-2004, 12:31pm
Just leave it alone & learn to love your tailpiece no matter how grungy it may become...

sunburst
Feb-24-2004, 12:47pm
Actually, ebony is not very stable. It can expand with moister air conditions, and could possibly split the block. Of coarse, if the pin is plastic, ignore all this.

The block is probably mahogany and is more stable than an ebony pin, but a hole in a piece of wood behaves the same as the wood. In other words, if there is a hole in a piece of wood and the wood swells, the hole gets bigger too (and changes shape). The reason end pins get tighter when the humidity goes up is because the ebony expands more then the hole does due to the higher stability of the block.

Here's a little scientific info to back up the stability difference between mahogany and ebony:

Approximate shrinkage as a percentage of green dimension, from green to oven-dry moisture content
tangential radial

Mahogany (Swietenia spp.) 5.1 3.7
ebony (Diospyros spp.) 11 7

Smaller numbers mean more stable, large numbers mean less stable.
All this really means is that ebony will shrink and swell a little over twice as much as mahogany.

Chris' explanation of how to get the pin out is right on, if you have the appropriate reamer.
If you don't you could try drilling a hole in the pin the right size to accept the tip of a soldering iron. Turn on the soldering iron, put the tip in the hole, and wait for the pin to get hot enough to melt the glue. It would probably be a good idea to mask off the surrounding area with aluminum foil to keep the heat from possibly dammaging the finish.
Grip the pin with a pair of pliers and give it a twist occasionally so you know when it is hot enough to move, and pull it out. Don't wait too long, there are other glue joints near by that you don't want to take apart.

Chris Baird
Feb-24-2004, 2:17pm
Thanks for the correction. I thought ebony was more stable than that.