I thought that you might like to see this clamp/jig that I made up for gluing the reinforcement strip down the centre of the back. It’s made from some U section steel with nuts captive within it. The clamp is clamped down at either end of the reinforcement strip and the machine screws can then be tightened up to apply pressure along its length. Hope you find it useful!
You’ll notice that I have the grain running along the length of the back rather than at 90 degrees, hence the books call it cross banding and I, a reenforcement strip. However, I prefer to do it this way. Why? Well- when the moisture content of wood changes, the wood will shrink or expand across the grain and not along its length. Also, the majority of moisture is lost from the end grain and really cross banding is nearly all grain! So, hopefully you can see that the back reinforcement strip with the grain running length-ways should be much more stable and lees likely to distort the back with changes of humidity.
I’ve had this piece of figured ash in the workshop for quite a number of years and the other day I picked up on a thread on the Mandolin Cafe forum (one of the more intelligent forums!) about building electric mandolins and ker-ching! Not knowing too much about e-mandos I posed a few questions and got back some very good responses, so watch this space..................
Labels: Handmade guitars, Luthier