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Bit Confused
09-03-2020, 01:23 PM
Want to get a TDL-1TP (custom order) kit and put a bigsby B70 on it, I know how to put one on a flat-top guitar, so you don't need to help me there. I was just wondering what angle shim I would need to make the string break angle not a problem.

Simon Barden
09-03-2020, 08:24 PM
You need to work back from the ideal bridge height. With the neck adjusted to be flat, and the bridge adjusted to be in roughly the right height for the Bigsby, a straight-edge placed along the neck should hit the bridge about 2mm below the top of the saddles.

You are less worried about shim 'angle' as the 'height' of the shim, as you'll only need a shim under the body end of the neck pocket 8-10mm wide at most. You won't need a very large shim, as there's roughly a 1:5 scaling on shim height to extra height at the bridge location. So a 1mm thick shim should raise the string height by about 4-5mm. I normally use a piece of hardwood veneer for a shim, though hard plastic (like an old credit card) is also fine.

You won't need a huge string break angle from the bridge to the string retainer bar on the Bigsby. Enough downward force to keep the strings in place, but not so much that there's too much friction over the saddles which will cause tuning issues. The strings should never be touching the rear of the bridge if at all possible.

If in doubt, try it out and then take and post a photo for comment.

To save wasting strings when taking bolt-on necks off and on a again, I loosen the strings off, then use a capo up by the nut to keep them in place, then unscrew the neck, add (or remove) a shim (or adjust the truss rod if it's a heel-end one), screw the neck back on, remove the capo and re-tighten the strings. Still a bit of a PITA but fairly easy to do.

Bit Confused
10-03-2020, 02:37 PM
As I said, haven't bought the kit, just planning what I'm going to do (It's my first kit and I've been planning how it's going to work for months now)