fine grit hammer filing

[Dave Nereson]

----- Original Message ----- 
From: "Farrell" <mfarrel2@tampabay.rr.com>
To: "Pianotech" <pianotech@ptg.org>
Sent: Friday, November 12, 2004 3:36 PM
Subject: Re: fine grit hammer filing


>MessageDon, I'd hate to think I know even one little thing that you don't 
>know, but........
>"For badly worn hammers or removing a lot of felt on new hammers I start 
>with 180 or 220 grit strips..."
>I guess you just haven't seen (or have forgotten) BADLY WORN hammers. Some 
>are so bad (we are >router!

>Terry Farrell

    Amen.  Many old uprights I run into have never had the hammers filed in 
their lives and the string grooves in the bass can be 1/4 deep.  Tenor and 
treble hammers can look like someone took a belt sander to the crowns!  Even 
with 40-year-old consoles and spinets, the grooves can be 1/8" deep or more. 
Start with 180?  Not hardly.  More like #36 or #40 grit.  That's right. 
Just a little finer than the stuff used for sanding hardwood floors.  If 
they're not quite so bad, I'll start with 50 grit, and in the high treble, 
if the grooves are down to the wood, I'm forced to use something finer.  And 
no, I'm not removing more felt than necessary -- just enough to get to the 
bottom of the string grooves.
    Even on hammers that just have string indentations rather than actual 
ruts, I've usually started with 50, then done a final pass with 100 or 120. 
If I did the first pass with grits that fine, it would take all weekend to 
file the whole set.
    But now maybe I'll try some of the finer grits ... just seems like using 
a scissors to mow the lawn.
    --David Nereson, RPT