January 17, 2009

As mentioned, my dilemma and setbacks with the warped walnut back prompted a posting on frets.net seeking advice on how to work through or remove the warp.  A responder suggested I place the back pieces on a concrete floor with a plywood cover, then weighed down with about 50 lbs. and let sit for a week.  I did such, and it pretty much worked as advertised.  Although the warp did not entirely disappear, it reduced considerably, and I was able to resume with joining, backstrip reinforcement, and bracing without the disaster previously encountered.

090117flattenamp.jpg

This is a good example of what to do with that old Peavy amp that you’re not using anymore.  It’s heavy, and balances nicely on a 5 gal paint can on the plywood cover of the back plate (sticking out in the foreground).

090117flattenback.jpg

I scraped off the leftover backstrip reinforcement scarf, and rejointed the back plates with my custom shooting block.

090117shootingboard.jpg

Decided this time to put the back plates face down in the joining jig to assure the backstrip and plates aligned flush down against the jig bars.

090117rejoinback.jpg

I’ve got to reexamine my threading pattern for this jig.  I think I need to add another “loop” at each bar to avoid driving the cross to the far end.

After curing sufficiently, I removed from jig and was pleased with the results.  Sanded smooth along the backstrip and installed the reinforcement strip.

090117reinforcement.jpg

The following shows the 15′ radius applied to the back braces, which are ready to install once the backstrip reinforcement has time to dry.

090117backbraceangle.jpg