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I'm a small-town tuner working on improving my technical/repair skills, and setting up to some practice restringing in my shop before getting anywhere near doing the procedure on a client's piano. There's a bridge question on this grand that I can't find a clear answer to and would appreciate your expertise. When restringing, is it standard to replace bridge pins even if the bridge does not need repair? This instrument has one or two pins where there's some minor splitting, and I can epoxy and repin that. But the remainder of the bridge is in good shape, except that the pins themselves appear to have rust and corrosion on them. If I replace the old pins, do I need to worry about increasing the size of the pins to ensure a tight fit in the old holes, or is the answer a complete epoxy and re-drill job? All of my references deal with what to do when the bridge is damaged, but are less clear on what to do when the bridge seems solid but the pins are in poor shape. Thank you for your thoughts!

EvanH,

In my experience, it is more important to have good TIGHT pins rather than worry about the surface condition. If they are tight, just some quick minor abrasion (such as with a guitar fret "eraser") will clean them up nicely. If they are not tight (but not too bad) you can use CA or thin epoxy (heat the pin to promote penetration). It is a judgement call IMO.

Peter Grey Piano Doctor

I would repair the splits and try to clean up the existing bridge pins. See how it looks.
It’s not standard to replace the pins when restringing unless there is a problem.
I like to use the exact size or very slightly larger if a match is not available.
I like to swab the holes with thin CA glue before driving in new pins. This will help with a snug fit and migrate into tiny splits that may not be visible.
Epoxy and re-drilling is not an option for me.
Also take a look at access especially where pins are under struts and you may not be able to remove them unless you remove the plate.
If your not careful, replacing pins can cause problems.

what about rotating them if they are grooved

I have pianos under my care that were restrung without a careful reconditioning of the bridges. It is depressing to look upon such wasted opportunity. Careful attention to all string terminations is critical for good piano tone.

If you have access to back issues of the Piano Technicians Journal (available free online for all Piano Technicians Guild members), by all means look at Bill Spurlock's "Bridge Repairs for Better Tone", published first in May 1992, then reprinted in August 2015. There is also a helpful discussion about bridge work in the November 2011 journal.

Spurlock outlines the process of removing the bridge pins, sanding the bridge top, re-carving the notches, re-drilling bridge pin holes if necessary, seating new pins in epoxy, and dealing with splits in the bridge. Not everyone is going to go the epoxy route, but it's still worth reading about. I do, in fact, use the epoxy.

On one occasion I found the bridge pins I removed from a piano were rounded on both ends. In that case, I simply inverted the pins and reused them. Otherwise, I use new pins.

If one is serious about doing comprehensive rebuilding of pianos, having the skills to recap a bridge, and make a new layout for speaking lengths and bridge pin spacing is strongly advised.

Much tone is lost at the bridge because the strings are not held to the pins well. The wood of the bridge gets "punky" if the pins/strings are rusting. I use thin CA for treating healthy bridges when I am restringing, but if the wood is punky; I want new wood around the new pins.

If you are interested in pursuing recapping bridges. I have several videos on my youtube channel showing all the steps.
Here's one.


-chris

Thank you, all! This is tremendously helpful information. Looks like there is a great deal of skill-building ahead of me.

Thank you, all! This is tremendously helpful information. Looks like there is a great deal of skill-building ahead of me.

The wood needs to be carefully selected. You want perfectly quarter-sawn hard maple with "boring" grain. No wildly variant grain widths or wavy stuff.

You also need to keep in mind which direction the wood will plane smoother in. This is called "rising" or "falling" grain. It is generally best to place the new cap stock so you can plane the surface easier from bass to treble.

If that was directed to me then I would like to reply. If not, then just ignore my answer.

I now use quartersawn hickory for my bridge caps, it just simply is superior to even the best quality select Hard Maple. The long grain and high density gives a crystal clear tone. After you hear a hickory cap and go back and listen to a Maple cap, you can hear how the maple, in a subtle way, gets in the way.

That is very good advice on the rising grain, not only for the reason you mentioned, but it also leaves the "going against the grain" for the less important rear notches.

-chris