[pianotech] Pitch change, etc.

[Terry Farrell]

Hi Will,

That Ron guy who responded to your post has a great POWER notcher -  
easy for him to say it's not hard to hand-notch! That being said, it  
may just be my poor notching skills, but I did make up a cap of  
quarter-sawn 0.5 mm laminations early on in my cap building efforts  
and found it quite difficult to notch. Yes, I could do it, but it sure  
didn't look very good. Again, maybe it's my lack of notching skill,  
maybe the quarter-sawn is more difficult to chisel smoothly than flat- 
sawn - I don't know. No reason for you to not give it a try though.

What I have been doing is building laminating caps with quarter-sawn  
1.5 mm laminations. I'll usually have about six laminations in a cap.  
These I find easier to hand notch as you are usually only going  
through two bonding surfaces or so.

Do they perform as well as the thinner laminations (stability,  
clarity, etc.)? I don't know for sure as I have not ever tested side- 
by-side. They do however seem to work quite well. I also set each  
bridge pin in epoxy (put epoxy in hole and on pin).

I apply unthickened epoxy to the notches, but not to the bridge top  
(leave it nakey).

I haven't been using any filler on my caps. I used some one time and  
it made the epoxy white - I like the looks of the clear. When I bond  
the laminations together, I wrap the assembly in plastic to retain the  
oozing epoxy - works quite well.

Some things to think about anyway. Let us know what route you end up  
going and how it works out. BTW, I know a guy down in Florida who  
actually builds the type of cap I have described here and sells them  
to the trade!

Terry Farrell

PS: You live in Massachusetts and can't find good hard  
maple?!?!?!?!?!?!?!

On Apr 6, 2010, at 5:50 PM, William Truitt wrote:

> I find the idea of the epoxy laminated caps very interesting, in part
> because of the difficulty in consistently getting good hard rock maple
> bridge stock.  I can't speak to the tuning stability, but it would  
> seem
> likely that the epoxy saturation would form a vapor barrier  
> throughout the
> wood, thereby negating the effects of humidity on the cap and any  
> movement
> of the wood associated with that.
>
> I had wanted to roll my own epoxy laminated bridge caps for my last  
> rebuild,
> but was unable to find a supplier for the veneers required to make  
> up the
> pieces.  I did chase one idiot supplier for 6 weeks, but could not  
> get him
> to send me the veneers before I gave up on him.
>
> Any recommendations for a supplier, anyone?  I'm starting a B in a  
> month or
> so that will get a new board and caps.
>
> Will Truitt