Backcheck Height

[Farrell]

Trying to regulate checking on a YC small grand action. After putting a nice radius on the tails, the backchecks need to move in a tad for 1/2" to 5/8" checking. On the bigger hammers in the lower tenor and bass, the backchecks are tall enough to touch the hammer felt and not permit the hammers a full return to resting position. There is a 3/16" to 5/16" overlap of the hammer tail and backcheck top at full key depression.

Do I need to push these backchecks further down into the key? The answer seems obvious to me - yes - but I have simply never run into this before and am looking for a reality check.

And if I need to press the backchecks lower, how do I do that (never done that either)? I know John Hartman showed his handy little rig for this in a recent PTG Journal article. But I don't have that jig. Maybe now is the time to get one? Use a drill press? Any other suggestions?

Thanks for any input.

Terry Farrell

P.S. Bill Spurlock's Grand Hammer Tail Arcing Jig is awesome!!!  Has this guy gotten some kind of medal yet for his contribution to piano technology???