floating plate threads

[Richard Moody]

Double threads?  and I thought nosebolts.  OOops Maybe I gave out a
patentable idea.  Hope I get my two cents worth.   
Richard Moody  
RR3 Box 83A
Platte South Dakota 57369

----------
> From: Charles E Faulk <cfaulk2@juno.com>
> To: pianotech@ptg.org
> Subject: Re: floating plate threads 
> Date: Wednesday, June 04, 1997 1:14 PM
> 
> List
> 
> Having worked in the Baldwin grand factory for many years, perhaps
I can
> shed a little more light on the floating plate legend. The concept
is
> basically the brainchild of long time R&D engineer, Harold Conklin.
The
> double thread system coupled with the Accu-Just hitch pin was
conceived
> primarily to facilitate manufacturing. No need to plane bridge tops
or
> build up plate boss supports. It's a tremendous time saver. The
plate
> need only be lowered into the case once. Bridges can be made to one
> specific thickness and never altered (since Baldwin bridges are
> vertically laminated with no cap, planing would be difficult). The
fact
> that downbearing can be set with great accuracy is an added bonus. 
> 
> However plates made in this country carry a great deal of
inconsistency
> since the primary supplier (O.S. Kelley) still uses the antiquated
wet
> sand casting method. So even though Baldwin can suspend a plate
above the
> rim using double threads, that doesn't mean that the downbearing
can
> always come out right in relation to the tubular hitch pin. It was
always
> amusing to me to see workers using clamps and padded blocks to warp
a
> plate down before running the plate bolt into the rim. The SD-10
plate
> has amazing flexibility; I've seen them bend it up and down
anywhere from
> 1/4" to 1/2" to get the height correct (sorta like a big iron taco
> shell).
> 
> I still have a lot of respect for Baldwin's engineering marvels.
> Unfortunately when I left the company 10 years ago, they were more
> concerned with cost cutting than innovation. Hopefully that might
be
> changing.
> 
> Regards, 
> 
> Charles Faulk RPT
> Manhattan, Kansas