Epoxy Man Strikes Again

[Delwin D Fandrich]

----- Original Message -----
From: "Ron Nossaman" <RNossaman@cox.net>
To: "Pianotech" <pianotech@ptg.org>
Sent: March 08, 2003 11:22 AM
Subject: Re: Epoxy Man Strikes Again


>
> >My first bridge that I will be gluing on has rib spacing varying from
> >about six inches to three inches apart. My understanding is that you
> >suggest that one screw/button placed every three to six inches (mid way
> >between each rib) along the bridge will provide sufficient clamping for a
> >Tightbond joint?
>
> Yes, it always has.

Ditto.


>
> >Might the fearful feel better if a larger block of wood is used
> >temporarily instead of a button?
>
> You can if you like, but it won't measurably improve the joint. Truly, it
> works just like we said, and produces a joint that far exceeds the minimum
> physical requirements for that joint.

I've considered this but only because the buttons sometimes break. You'll
get quite an adequate joint with just the buttons.


>
> >With your process do you see good glue squeeze-out mid-way between screws
> >(as in on the top side of the board at rib locations)?
>
> Yep. You know the bridge isn't going to deflect much in that 6" span, and
> that 8mm spruce panel isn't going to let the resistance offered by a small
> pool of Titebond bend it enough to spoil the joint either. Not by a long
> shot.

Yup.


>
> >Maybe part of my problem is I am imagining this floppy panel - but I
> >suppose it won't be so floppy after ribs are attached.
>
> Yes, the ribs make it stiffer in the direction in which it was floppy, and
> in the other direction, it never was floppy enough to be a problem. Wave
> that panel around some after you get the ribs on. Pound on it. Push on it.
> Try to bend it (careful of the edges, and don't dent it up). Marvel at how
> something that relatively light can be that stiff. That thing becomes it's
> own clamping caul.

Yup.

Del