[pianotech] Notching Machine Maiden Voyage

[Paul McCloud]

Jim:
That is nice!  You gotta be pattin' yourself on the back for that one.  Hey, I'll do it for you!  Beautiful work.  
Paul McCloud
San Diego

----- Original Message -----
From: "Jim Ialeggio" <jim at grandpianosolutions.com>
To: pianotech at ptg.org
Sent: Monday, February 18, 2013 7:33:18 PM
Subject: [pianotech] Notching Machine Maiden Voyage

I've been working on this bridge notching machine on and off for a 
while. Finally got all the bits and bugs worked out. It's cutting 
notches cleanly, relatively safely and efficiently.

To make the notch, the bridge is mounted cap side down on a powered 
sliding table. The sliding table runs on linear motion bearings, powered 
by a 12v linear actuator (automobile power window actuator). It's set up 
with a self latching solid state relay and 2 micro switches. This means 
the cut cycle is automatic and hands free, and controlled through the 
potentially dangerous climb cut. Motion is slow steady and slop free.

The notching machine is temporarily mounted on the table saw when in 
use, but its only on the table saw to run the cutterhead off the table 
saw arbor.  2" diam cutterhead spins@ 7000rpm.

Set the cut up by aligning the drilled bridge pin holes with a kerf that 
the cutterhead has cut in a sacrificial backer.  A mirror mounted on the 
non-sliding base near the cutterhead gives clear sight of when the 
bridge is lined up correctly with the backer board.

The sliding table/integral clamp and clamped bridge are the only things 
that slide during the cut. The cutterhead remains stationary, skewed 1 
deg from square to table travel.

The weird shaped  secondary clamping board's purpose is to be able to 
clamp the bridge at 2 points, instead of just one point. This, 
particularly in this design, is essential, because the bridge will have 
a tendency to rotate during the cut unless restrained at a second point. 
In use the whole setup was pretty easy to use, even on a maiden 
voyage... even though I'm still learning what it likes to do and what it 
doesn't like to do.

It was originally inspired by a desire to use a epoxy laminated bridge 
cap, Nossaman style with veneer & epoxy. On this job though, I had to, 
at least temporarily, abandon the epoxy lam cap because I was not 
comfortable with the adhesion I was getting between veneer laminations. 
This cap is 3 laminations w/titebond.

Jim Ialeggio






-- 
Jim Ialeggio	
jim at grandpianosolutions.com
978 425-9026
Shirley Center, MA