Pin torque - project

[Farrell]

You are welcome. I have found that my results vary from the results of that
study, but I suppose that may be related to all the different variables that
one introduces in their own shop. I am using the Schaff 11-ply maple
pinblock (I think the plys are rotary cut, but not sure). I found that a
1/4" drill bit get me right at 150 to 160 inch-pounds pretty consistantly.
The study relfected about 200 inch-pounds for that combination. I guess
folks are right when they say to do a bunch of boring and testing to find
what works.

One interesting item I noted was when I first posted I said that I was
having trouble getting more than about 100 inch-pounds of torque. What was
really wierd was that I was getting the same torque whether I used a 0.272
inch drill bit or ranged down to 0.250 inch. I was pounding the pins into a
test piece on the concrete shop floor with a small sledge hammer - and I
noticed that I was having a bit of trouble getting the pins to ride straight
into the bare block. The next day I decided to place the sample block onto
the table (to simulate its height in the piano) and use the same hammer
(smaller) that I used quite successfully on my last repinning/restringing
job. Suddenly pins went in straight, a 0.262 bit produced a torque of 200
inch-pounds, and the 1/4" bit worked great. So, the bottom line I think is
that even if everything is the same (which it will never be from shop to
shop), if a different person whacks away at the pins, a differing torque
will likely result. And so, like those much wiser than me often say,
experiment and then do what works for you.

Terry Farrell
Piano Tuning & Service
Tampa, Florida
mfarrel2@tampabay.rr.com
----- Original Message -----
From: "Paul" <tunenbww@clear.lakes.com>
To: <pianotech@ptg.org>
Sent: Thursday, October 19, 2000 8:37 AM
Subject: Re: Pin torque - project


> Terry
> Thanks for the repost of the pinblock/drill size data. I've been curious
> about what drill size affects have on a variety of blocks.
>
> Paul Chick
> ----- Original Message -----
> From: Farrell <mfarrel2@tampabay.rr.com>
> To: <pianotech@ptg.org>
> Sent: Thursday, October 05, 2000 6:41 AM
> Subject: Fw: Pin torque - project
>
>
> > Hey Ron N. I think you cited this post from last March recently in reply
> to
> > one of my posts. Here it is again for anyone that wants it!
> >
> > Terry Farrell
> > Piano Tuning & Service
> > Tampa, Florida
> > mfarrel2@tampabay.rr.com
> >
> > ----- Original Message -----
> > From: "Mike McCoy" <mjmc@attglobal.net>
> > To: "Pianotech" <pianotech@ptg.org>
> > Sent: Wednesday, March 08, 2000 2:37 PM
> > Subject: Re: Pin torque - project
> >
> >
> > > Hi all,
> > >
> > >  Our PTG Chapter started a pinblock project in 1996 with 8 different
> > > pieces of pinblock, each piece drilled with 10 different size holes
and
> > > all pinned with number 2 pins, torque readings were then taken on each
> > > pin in 1996 and again in 1999. The following is cut/pasted from a
Lotus
> > > 123 spreadsheet so the columns are off a bit but you can figure it
out.
> > > If anyone wants the 123 file just ask. No one remembers what type of
> > > block number 6 was... oh well.
> > >
> > > Drill Size   Letter Fraction Metric #1 - Sohmer 5 ply Maple
> > >
> > > June 1996 Sept 1999
> > > 0.25 1/4" 6.35 210 185
> > > 0.252 6.4 210 180
> > > 0.2559 6.5 205 175
> > > 0.2571 F 6.53 180 170
> > > 0.2598 6.6 175 160
> > > 0.261 G 6.63 160 150
> > > 0.2638 6.7 150 125
> > > 0.2657 17/64" 6.75 148 130
> > > 0.2677 6.8 148 130
> > > 0.2717 I 6.9 140 120
> > >
> > >
> > > Drill Size Letter Fraction Metric #2 - APSCO Dilignit - 18.5 PPI Beech
> > >
> > > June 1996 Sept 1999
> > > 0.25 1/4" 6.35 275 255
> > > 0.252 6.4 265 225
> > > 0.2559 6.5 280 250
> > > 0.2571 F 6.53 280 250
> > > 0.2598 6.6 280 245
> > > 0.261 G 6.63 280 225
> > > 0.2638 6.7 275 230
> > > 0.2657 17/64" 6.75 265 225
> > > 0.2677 6.8 250 200
> > > 0.2717 I 6.9 220 185
> > >
> > >
> > > Drill Size Letter Fraction Metric #3 Baldwin 49 ply Maple
> > >
> > > June 1996 Sept 1999
> > > 0.25 1/4" 6.35 180 145
> > > 0.252 6.4 190 145
> > > 0.2559 6.5 190 150
> > > 0.2571 F 6.53 205 160
> > > 0.2598 6.6 175 145
> > > 0.261 G 6.63 200 155
> > > 0.2638 6.7 180 145
> > > 0.2657 17/64" 6.75 180 150
> > > 0.2677 6.8 150 140
> > > 0.2717 I 6.9 140 110
> > >
> > >
> > > Drill Size Letter Fraction Metric #4 - Bolduc 5 ply Maple
> > >
> > > June 1996 Sept 1999
> > > 0.25 1/4" 6.35 230 190
> > > 0.252 6.4 230 200
> > > 0.2559 6.5 200 165
> > > 0.2571 F 6.53 220 185
> > > 0.2598 6.6 215 185
> > > 0.261 G 6.63 190 155
> > > 0.2638 6.7 160 115
> > > 0.2657 17/64" 6.75 180 150
> > > 0.2677 6.8 160 145
> > > 0.2717 I 6.9 110 95
> > >
> > >
> > > Drill Size Letter Fraction Metric #5 Schaff Dilignit
> > >
> > > June 1996 Sept 1999
> > > 0.25 1/4" 6.35 230 190
> > > 0.252 6.4 230 200
> > > 0.2559 6.5 225 185
> > > 0.2571 F 6.53 225 185
> > > 0.2598 6.6 215 175
> > > 0.261 G 6.63 200 150
> > > 0.2638 6.7 205 160
> > > 0.2657 17/64" 6.75 200 160
> > > 0.2677 6.8 175 160
> > > 0.2717 I 6.9 150 135
> > >
> > >
> > > Drill Size Letter Fraction Metric #6 ???? 14 PPI Beech
> > >
> > > June 1996 Sept 1999
> > > 0.25 1/4" 6.35 150 125
> > > 0.252 6.4 145 125
> > > 0.2559 6.5 145 120
> > > 0.2571 F 6.53 145 125
> > > 0.2598 6.6 140 120
> > > 0.261 G 6.63 130 120
> > > 0.2638 6.7 110 90
> > > 0.2657 17/64" 6.75 105 95
> > > 0.2677 6.8 80 75
> > > 0.2717 I 6.9 75 65
> > >
> > >
> > > Drill Size Letter Fraction Metric #7 - Falconwood 20.5 PPI Maple
> > >
> > > June 1996 Sept 1999
> > > 0.25 1/4" 6.35 380 340
> > > 0.252 6.4 360 325
> > > 0.2559 6.5 380 320
> > > 0.2571 F 6.53 360 310
> > > 0.2598 6.6 350 300
> > > 0.261 G 6.63 275 235
> > > 0.2638 6.7 380 325
> > > 0.2657 17/64" 6.75 380 330
> > > 0.2677 6.8 350 315
> > > 0.2717 I 6.9 305 250
> > >
> > >
> > > Drill Size Letter Fraction Metric #8 - Schaff 11 Ply Maple
> > >
> > > June 1996 Sept 1999
> > > 0.25 1/4" 6.35 210 185
> > > 0.252 6.4 210 180
> > > 0.2559 6.5 205 175
> > > 0.2571 F 6.53 180 170
> > > 0.2598 6.6 175 160
> > > 0.261 G 6.63 160 150
> > > 0.2638 6.7 150 125
> > > 0.2657 17/64" 6.75 148 130
> > > 0.2677 6.8 148 130
> > > 0.2717 I 6.9 140 120
> > >
> > >
> > >
> > > --
> > > Mike McCoy
> > > So Central Pa Chapter 170, PTG
> > > Middletown, Pa
> > > Mailto:mjmc@attglobal.net
> > >
> >
>