Saturday 11 February 2012

F-board slot cutting

The fixture used on the Moon Bass was built around a flimsy mini-drill that had a flexible shaft and a small circular saw at the end. This possessed much better timing than I normally do when playing as the flexible shaft sheared as I finished cutting the last slot. Phew!

This time I used a proper Dremel, and got hold of their mini circular saw attachment which is a bit more sturdy. I had to get some 18mm MDF sliced up at the local B&Q place as they cut so much straighter than me, and then pieced all the bits together.


Of course, the granite bed and GPS controlled servo system may have worked, but up against steel 19" rack hardware, kitchen drawer slides and a small piece of 40mm thick laminated chipboard, that kind of old-hat technology was never going to get very far ;-)



I had to whittle a matching strange shape so that the Dremel saw could be clamped as there is no specific way of fixing it.



I had previously used a small 1mm drill in a milling machine at work to mark where the slots should be accurately-ish, and all this jig has to do is allow a perpendicular cut to be made. Sounds easy.



The perspex now sports freshly cut slots, and in the right places. It doesn't get better than this. Well, not round here anyway. The fboard was carefully prised away from the extremely sticky double sided tape, and after a quick degunk with acetone, the fboard was glued onto the neck with more epoxy resin.


The bond was held in place by a couple of clamps, and a really nice transformer that Robin found in his garage. This looks to be approx 300VA and measures 125 x 125 x 110mm. It has a split primary and binary weighted secondaries. It sounds *perfect* to replace the feeble 50VA toroidal unit in my 50W valve amplifier as an output tranny. I'm using it here as a bloody great weight, but I can see its potential elsewhere...


Now the glue has dried, the chips are down, the word is out, and the time is right. The edges have been trimmed back and it is starting to look like perspex wasn't such a bad move. I think the final proof of that one will be when the frets get bludgeoned in ;-o

Oh, I rigged up the transformer (bypassing the toroid) and it sounds glorious! I can see the next dilemma coming up on the horizon as there is no way this chunk of iron is ever going to fit in the valve amp's 3U case. I will just have to make a bigger one...