composite block warping

[Ron Nossaman]

> Hi Ron and Bob,
>  
> I have seen what Bob is talking about. In fact, that has occurred on a 
> block I am capping right now. I'd really like to see the process used to 
> build those Multilam pinblocks because with SOME of them, when you cut 
> off a thin layer so as to end up with the target thickness pinblock 
> after capping, the sucker can spring into all sorts of curves. The one I 
> am $%&#ing with now sprang into an arc with a radius of nine meters or 
> so. When you laminate the cap on, the cap isn't going to flatten the 
> thing much at all if you do the glue up flat. With that kind of a curve, 
> even if you stand on the thing in the middle, it doesn't go flat - hey, 
> even if /*_I_*/ stand on the thing it doesn't go flat. With that kind of 
> curve, even if I could draw it up to the plate, I would be concerned 
> about cracking the plate or at least bowing the plate.
>  
> Naw, too much curve to let me sleep at night. In these kind of cases, it 
> seems the trick is to somehow calculate how much reverse curve to induce 
> into the structure when bonding the cap to the block to end up with a 
> flat block in a two lamination structure.
>  
> By chance you got a formula for that Ron? Let me give you a hint: My 
> first guess wasn't even close..... (I went overboard and actually 
> reversed the troublesome curve!).
>  
> Terry Farrell

Terry,
Maybe I've just gotten lucky and not gotten a really wild one 
*yet*, though the very next one will probably be it, now that 
it's been brought up. I've had them curve a little bit, but 
nothing that was a problem. More of an annoyance for getting 
the thing to lay down to fit it to the plate. There are plenty 
of folks using the multi-lam blocks "neat" who (I'd hope) 
plane them to required thickness instead of going with the 
nearest 1/8". If they are similarly annoyed, they haven't said.

A formula? No, I've just clamped them flat and pressed on. If 
I were formulatin' though, I'd probably start with half the 
crown height for counter spring.

Bob, Terry, a question. What side of the block are you gluing 
the cap to, the cut side, or the factory side?

Ron N