January 23

Easing Key Bushings

Repairing, Regulating, and Evaluating Pianos

4  comments

This is a novel way to ease key bushings. The standard way is to iron them or compress them. This way actually shaves them.

A key may bind on the balance rail pin or the felt bushings.

 

I use a standard large set of tweezers. They need to be the right size.

 

To ease the balance rail hole, I just insert the tweezers end into the hole. Be careful; not too much.

 

To ease the felt bushings, I insert the tweezers and move them back and forth.

  

 

I've always done this and never really understood why it worked so well. I thought I was just compressing the felt.

Then one day, I looked at the tweezers.

 

I found powdered felt. I realized the tweezers were shaving the felt! No wonder it worked so well!

About the author 

Mark Cerisano, RPT, B.Sc.(Mech.Eng.)

Instructor and Founder, howtotunepianos.com

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