[pianotech] bridge notching machines - search-able title

Ron Nossaman rnossaman at cox.net
Mon Oct 18 15:39:48 MDT 2010


On 10/18/2010 4:16 PM, jimialeggio wrote:
>
>> The table lifts pneumatically to clamp the bridge to the stationary
>> hold down,
>>
> Given the pushy-ness of the climb cut and the fact that the clamping
> happens only at one point, when you are at the treble or tenor extreme
> of the bridge, the entire rest of the bridge has the potential to behave
> like a naughty lever. No matter how hard I clamp, I find a single point
> clamp still lets things pivot. How do you deal with naughty lever
> syndrome...and have you seen your doctor about it?

Single point clamping anywhere but directly in line with the cutter path 
is a pending disaster. With the hold down directly in line with the 
cutter, and never far away from it, there's no tendency at all to 
rotate. Force and resistance vectors coincide. PSA backed abrasive on 
the table for traction, keeps the cutter from sucking the bridge 
straight into it, and I have an auxiliary "prop", clamped to the base, 
that I move around as necessary to support the weight of the long end 
off of the table.

Ron N


More information about the pianotech mailing list

This PTG archive page provided courtesy of Moy Piano Service, LLC