geoff-bristol wrote: ↑
Tue Sep 19, 2017 10:11 pm
... So even with a 2mm neck rise that equates to an angle of about 1/3rd of a degree... at the heel cut. Just about markable with a sharp pencil !
I'm not sure i would be able to measure if the sides at the heel were out of square by 1/3rd of a deg ?
This is exactly right, and why a lot of experienced makers don't think it's worth fussing over.
If you're using thick laminated sides, or have heavy laminated linings already glued to the sides, you might feel a little tension when you bend the neck down by that tiny amount. Using the Spanish method, however, with sides <= 2mm thick, and with kerfed linings (which are still flexible of course once glued to the sides) you should feel no tension whatsoever as you secure the sides into a heel block that has the slots cut at 90 deg.
Like others have mentioned, building tension into the guitar I also think is deleterious, but cutting the heel slots at 90 deg and bending the neck down by 2mm is not necessarily introducing any tension.
Extra tidbit - I wouldn't glue the neck to the top flat before bending down the 2mm of rake. Fit the shelf to the top in the 2mm rake position so the top doesn't get any bend in it. This helps a lot when fitting the fingerboard.