blow discrepancy:technique?

[Richard Brekne]

Depends on whether you are interested in the actual distance the hammer
actually moves... in which case you want to fiqure the arc distance.. or
whether you are just interested in how far away from the strings the tip
of the hammer is at rest position.. grin... we are getting a bit
nitpicky here for most uses. I like your colleagues suggestion as its
real easy and straight forward.

This measurement btw is not written in stone.. not for any piano nor for
any geometry except on paper. Nor are any of the other measurements that
interelate here. Get it within tolerances.. balance out the action so
that the relationships of dip, jack travel, letoff, checking, etc work
well with your hammer distance and go with it. Add spice according to
taste.

grin

David Renaud wrote:

> I have always measured a straight line from hammer tip to string.
>
> But:
> A colleague insists the best way to determine travel in an upright
> is to push a hammer molding forward to the stings
> with a ruler, mesuring from the back edges of the respective
> hammer moldings.
>
> I find that this method always produces a slightly reduced
> reading. On my action model a 1/16th reduced reading.
> This is apparently due to the hammer always traveling
> from an angled position to a perpendicular position relative to
> to strings. It will always reach slightly forward as it assumes a
> perpendicular position and block premature of its straight
> line measurement. So he could be right.
>
> But:
> The hammer is traveling though an arc. So it is greater
> then any straight line measure anyway. So I still I'm still right.
>
> Never thought much on this before. Was always concerned
> more with relationships working between travel distance
> and key travel for correct aftertouch then travel being 1 7/8.
> The test seems to support this as it gives +/- 1/8 to make it
> work. Never less in a test siduation 1/16+ difference due
> to measuring technique is too much.
>
> So is my hammer to string, straight line technique
> from the front of the hammer wrong?
> Or is is better to approach these measurements from the
> rear measuring molding to molding with the hammer engaged?
>
>                                                      Cheers
>                                                      Dave Renaud

--
Richard Brekne
Associate PTG, N.P.T.F.
Bergen, Norway