MIMF

Hello,
Anybody know if there is usually a back-set neck angle for the neck like on guitars? I am building with a Spanish heel and getting ready to cut the side slots.
Thanks.

I just reverse engineer this from my desired saddle height above the top.

Assume I want 10 mm bridge height and 3 mm of saddle, total 13 mm. My fretboard is 3 mm thick. I want 3 mm string height at the 12th fret.

If the neck had no angle this would place the saddle top at 9 mm (3 mm saddle plus 2 x my 3 mm 12 th fret height). I want 4 mm more, so the neck has to be angled back to give me 4 mm less at the nut (think of the neck as a seesaw/teeter-totter pivoted at the 12 th fret).

To achieve this with a Spanish heel I place a 4 mm spacer under the nut position (drill bits make good spacers) and then shape the neck past the body join to lie flat on my building board. Mark the slots vertically from the board, job done!

Thanks,
I get all of it but the "building board" part. I built a classical with spanish heel and solera (which I hated using) but don't remember very well.

Is your top flat? If so, use a flat board as if it were a solera.

With Spanish heel you have to attach the neck to the top before you fit the sides (unless you have a complicated mould I guess - would need pics to understand that).