[pianotech] Pinblock expensive experiment

[Duane McGuire]

Thanks for your ingenuity!  You are indeed adjusting my attitude.

Much appreciated!

On Sun, Apr 4, 2010 at 3:18 PM, Terry Farrell <mfarrel2 at tampabay.rr.com>wrote:

> You could simply resaw the capped block in half, flip the bottom over (top
> to bottom), clamp it together and see if that straightens things out. If it
> does look better, just glue it back together (I recommend either epoxy or
> two-part urea-formaldehyde). And even if it doesn't straighten it out
> perfectly, you can try again (only hopefully better this time!) to induce a
> little counter-bend to it that makes it end up straight. Will only cost you
> a little adhesive. And like David Love pointed out, the small loss of
> thickness from the saw kerf, you can make up with shims - or if you want
> that full thickness, simply laminate a layer or maple (or really any
> hardwood) to the bottom of the block to make up the full thickness.
>
> And if you end up screwing it up again, resaw the darn thing again and glue
> it back up!
>
> No problems mate! No reason to buy a new pinblock!!!
>
> Terry Farrell
>
> On Apr 4, 2010, at 1:31 PM, Duane McGuire wrote:
>
> I think that my first grand pinblock replacement has become an expensive
> experiment.
>
> I wanted to do the multi-lam capped with delignit block that Ron Nossaman
> described at Grand Rapids and was documented in the journal.   I resawed the
> delignit and planed a 9mm cap for the block.
>
> Before gluing up I noted that the multi-lam  (Schaff) was not exactly flat,
> but I did not measure its degree of bow (I believe this is the root an
> expensive mistake). I selected a clamping caul with a compensating bow, and
> glued the assembly up, thinking that it would tend to flatten out.
>
> After unclamping and planing the multilam to final thickness per the
> original block,  I find that the bow in the board is just plain awful.
> Total deflection measured at the midpoint of the board is 10 mm!  I'm
> thinking I have some more firewood for next winter.
>
> By the way, the original block measures 39.6 mm, and from my look at the
> suppliers, Bulduc's 1-5/8 is the only material that will match that
> thickness.   At the same time, I do suppose a person could place blocking at
> the ends, and use a somewhat thinner board.  From my starting, I didn't find
> that idea appealing, but I'm looking at this from every direction now.
>
> Right now my thought is that tomorrow I order a Bolduc pinblock and get on
> with it.
>
> But rather than just reacting to my own self-pity, I'd appreciate your
> input, before my wallet gets even thinner.   In the category of self
> recrimination, I expect that I should have measured the bow in that
> multi-lam and shipped it back when I found the degree of deflection that was
> present.
>
> Thoughts?
>
>
> --
> Duane McGuire
> 801-830-5858
> http://blog.duanemcguire.com
>
>
>


-- 
Duane McGuire
801-830-5858
http://blog.duanemcguire.com
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