Fretboard Radius

[cork sniffer]

Does anybody know what the radius on a PitBull ES-12G is?
Has anybody reduced (smaller circle) the radius on a guitar after the neck has been set?

[Simon Barden]

I think all the PB guitar necks have a 12" radius.

It's certainly possible to reduce the radius, but it's a frets-out/nut off job and really needs to be done before the neck is set, otherwise you're at risk of damaging the top around the neck. Though with masking and being careful, it is possible to do.

You can get pre-made radiused wooden sanding blocks, and then its just a question of lightly gluing sandpaper into the block, rubbing down and going through the grades.

The smaller the radius you go for, the more of the wood at the side of the neck you will take off, so you may find that you sand the edge off some of the dot side markers.

You'll need to get new fret wire, and either buy it pre-bent or bend it yourself to suit the new radius. You may need to cut the fret slots a bit deeper as well (with the correct width saw), as the depth at the sides will have been reduced. Once the frets have been inserted, you then need to cut the fret-ends off, file them at an angle, then do a fret levelling, reprofiling and polishing exercise.

A re-fret job isn't to be taken lightly, and you really need quite a few specialised (and fairly expensive) tools to do it well.

[cork sniffer]

I think all the PB guitar necks have a 12" radius.

Hmmm, the person I'd be changing this 12"? radius for is in love with a 7.25" radius guitar.
That suggests to me a dramatic reduction of edge material.

Edit, I'll do a paper scale drawing of each radius overlaid and see how they compare.

[Simon Barden]

That's a big radius change, though in reality its probably only around 1mm of each side of the fingerboard (though you'd undoubtedly end up taking a bit more off the height overall when sanding).

It's easier to play chords on a 12-string neck with the smaller radius, and as they probably won't be string bending on a 12-string, the action can still be kept fairly low.

[cork sniffer]

Simon, thanks for your comments.
A job to sleep on, not going to jump in without due caution.

[king casey]

I got to thinking (it must be nearly bedtime)... double basses tend to have a severe fretboard radius.
Charles Mingus could certainly put some speed into his.
So why not the electric basses?

cheers, Mark.

[Simon Barden]

Probably because of the playing position. Playing a vertical neck, your fingers can curve around the fingerboard a lot more (and they naturally want to) compared to playing a horizontal neck where your hand is already stretching hard just because of the position it's in.

A Double Bass fingerboard radius is generally a complex shape, but apparently is of approximately 95mm/3.75" radius. I think you'd do yourself some serious tendon injuries trying to stretch around that on a horizontal neck.

Horses for courses.

[king casey]

Probably because of the playing position.

Not saying it has to be the same...

The early Fender guitar had them...would have thought the basses would too.

cheers, Mark.

[Simon Barden]

The first Fender bases had a 7.25" radius just like the guitars did. But I have no idea why they changed. Maybe they used the same radiusing machinery in the factory for bass and guitar necks? The 7.25" guitar radius had issues with low action and string bending, so they moved to the 9.5" radius instead which was an improvement. Obviously not really an issue with bass necks.

But unless they trialled it and people preferred the flatter radius on basses as well, it's probably all down to something pragmatic.

Or maybe Leo cutting costs again as they could use a slightly thinner fingerboard top for the necks with the shallower radius and get more blanks out of the same piece of wood?

[Simon Barden]

Just found out that (on the guitars at least), they first went to a 12" radius in '83 then to the tighter 9.5" in '86. This was the period when there was a MBO from CBS in 85, so this was at the end of the CBS era.