Fretboard Radius

[verhoevenc]

How accurate exactly does the fretboard's radius need to be? Cause I'm sanding out an ebony board right now and it's proving to be alot more difficult to get a perfect 12" radius than I thought it would be? Even with a stewmac sanding block (the long one).

Also, I tapered the fretboard before sanding it... should i sand a little more at one end than the other to make up for this? Cause if i just sand until all flatness in the middle is gone i'm gunna end up with lower sides at higher frets...

Chris

[scottyd]

i've wondered this too, ive seen where some builders dont even use a block David King for one uses a big belt sander free hand. I use a block but theres been times where i would add relief freehand too...

[Setch]

Is the board glued to the neck yet?

If not, tape it to a flat worksurface, and clamp a straightedged piece of board on either side - run your radius block between these and it won't be able to move side to side, and produce a perfect radius.

Like so:

Don't sand more at the treble end, or you'll end up with a fretboard which is tapered in depth as well as width, which will mess with any neck angle calculations you've made. Almost all fretboards have slightly thinner egdes as you go towards the high frets, but it's such a small difference nobody notices.

You want the radius to be as perfect as possible, and using the rails to support the block there is no reason for it not to be perfect. Do take care to make you strokes in one direction only (not back'n'forwards)- otherwise you'll remove more from the centre of the board than either end.

[johnsilver]

+1 to what Setch said.

Here is a jig I made that works the same as Setch's in principle. I made up some 3/4" MDF with two parallel boards screwed to a base board. The two parallel boards are the right distance apart to fit my Stewmac radius block so it doesn't wander and maintains a straight line. I double stick tape the fretboard on the center line I've already established on the jig, and then sand away.

[verhoevenc]

Oh well, looks like I'm gunna have to freehand these two boards.... cause they're already tapered, on the necks, necks are shaped, etc.

Chris

[Guitarfrenzy]

I use a long radius block I made that's 18" long simply because I found it gives much better results than using those short blocks. There is a tendancy to sand a dip in the middle of the fretboard if your not careful with the short radius blocks. The long radius block contacts the whole fingerboard at all times when sanding, and eliminates any dips. I still want to buy the aluminum one that Stew Mac carries now, but so far the hardwood radius block I made works great and very highly accurate.

I wish I had a big belt sander like Grizzly's Fretboard Radius Sander System. You can do compound radius boards also, but it's not cheap, so you better be in full production before you buy something like this for just getting a fingerboard radiused.

[fryovanni]

I use the method as Setch. You should have thinner sides as the neck gets wider(at least if you have a true radius- it gets thinner as you move away from center).

Peace,Rich

[Mattia]

What those wise folks said; you can still clamp up your guitar and rig some guides to keep the sanding block aligned, but really, you want to do as much shaping as possible before gluing it down to the neck. After that it'll need a little bit of truing up, probably, but hardly anyway.

Oh, and thinner edges at higher frets is the norm, unless you do a compound radius board.