keyframe bedding

[John Hartman]

Bob Hull wrote:

> Thanks for the advice.  Finished the regulation today.  The solution to 
> getting the keyframe to bed was to take off the shim that was on the 
> front of the bass cheek block and to put a thinner one it its place. 
> This gave the right amount of downward pressure.  It did make the una 
> corda pedal a little stiffer, especially if you tighten the cheek block 
> screw too much.
>  
> Bob Hull, RPT

Sounds like you did the right thing. You say there is still a problem 
with shifting the action? Could be that someone else turned the pin or 
it is rough. Check to see if the pin is parallel with the key bed. If it 
points down the action will bind when shifted. Also try this: pull the 
action part way out and test the fit of the block on the pin. Does it 
run smooth. If not you can de-bur and polish it with emery paper.

I use Mclube 444 on the action frame's front and back rail. Apply it 
with a shoe polish swab. I use graphite stick on the glide dowel ends. 
Clean the return spring and lube the keyframe end with 444.

It is not absolutely necessary bit you should be able to get the action 
to shift with the block screws cinched tight.

John Hartman RPT

John Hartman Pianos
[link redacted at request of site owner - Jul 25, 2015]
Rebuilding Steinway and Mason & Hamlin
Grand Pianos Since 1979

Piano Technicians Journal
Journal Illustrator/Contributing Editor
[link redacted at request of site owner - Jul 25, 2015]