misfiring jack

[Richard Brekne]

Why dont you check what the down and upweights are, and perhaps temporarilly add
weight to the back of some of the worst offending keys to see if this helps ??



"H. Pengelly" wrote:

> Dear list, I recently tuned a Homer upright spinet that had a few
> miss-hitting keys. Upon closer inspection I noticed that the jack wasn't
> slipping back under the hammer butt. The key bushings are fine and the lost
> motion is set properly and the problem persists. Incidentally the action is
> miniature and the keys from the balance pin bushing are cut at a slope to
> clear under the wippens. It appears to me that the back of the keys are too
> light and sit up too high thus preventing the jack to return. If you press
> lightly down on the back of the key then the jack goes back. There are no
> weights in the keys and they are quite front heavy. When the soft pedal is
> depressed the problem is worse. The front of the keys dip as if the bridle
> tapes were too tight but they aren't. The weight of the action seems too
> light  to stop the keys from rising up at the back. In my 16 years of tuning
> this is a first for me,I know I've been lucky, and it has me perplexed. I
> could probably fix it by adding weights to the keys but it originally worked
> ok so what are your thoughts? Much appreciated
> John Pengelly

--
Richard Brekne
RPT, N.P.T.F.
Bergen, Norway