Setting bridge radius

[Forrest]

I'm trying to setup a bridge that originally had 2 shims on it, but when I got it back from the guy who worked on my guitar (6 years ago) it was disassembled. So I'm not sure where the shims were or if they were even positioned correctly.

I have a few quick questions:

I've read the Jackson compound radius necks are 12" to 16". Is this always the case? I'm using metal stew-mac radius gauges to measure and it actually looks closer to 14" at the 24th fret, on the guitar I'm currently working on (1991 USA Soloist.)

When setting the bridge radius on a compound radius neck, you want to match the largest radius, right?

With no shims under the saddles, the understring measurement, using the gauge, leaves a gap between the D,G, and B strings. This is due to string diameter differences, of course. Should I be shimming ADGB or just DGB?

I've read that the stock radius on an OFR is 10". What about the Schallers? Are they the same? Did either bridge come from the USA shop with shims? What about the Japanese factory? (I've encountered bridges without shims, but I'm not sure if they've been worked on previously.)

Thanks in advance.

[K.Dee]

Shim the E,A and high E so you can lower the action more and to minimize the gap of the centre strings.

[Forrest]

Shim the E,A and high E so you can lower the action more and to minimize the gap of the centre strings.

That's a very good point, I was looking at it backwards. Shimming the middle would make the problem worse. Are you sure I should shim the A, though? The only reason it is touching the gap and the B isn't, is because of the winding.

I'm somewhat frustrated that this stuff either isn't covered in either of these Dan Erlewine books, or it's not in the Floyd Rose section. I've only skimmed the other bridge writeups, but I can't find discussion on it. Nothing said about accounting for compound radius fretboards, either. The instructions that came with the gauges were a joke.

So, thanks very much for the help.

[DonP]

Are you using the under-string gauges? Those are more accurate because of string thickness. You want to measure the radius of the underside of the strings and match that to the top side of the fretboard and frets.

[MakeAJazzNoiseHere]

The typical Floyd nuts are 10" radius (R2, R3, R4, etc.) and the stock Floyd bridge radius is 10" with the metal shim under the A/D/G/B saddles, which is included from the factory in a boxed tremolo. When you remove it it's more like a 15" radius. I have never unboxed a Schaller so, I don't know on those.

I have never found any shims in any of my Jacksons or Charvels with Floyds. So basically a brand new USA Jackson or Custom Shop Charvel comes with a 10" nut and a roughly 15" bridge radius and they play pretty nice like that.

You can shim the bridge a little flatter using a slightly thicker shim under the E's, a shim under the B/A, and none under the D/G saddles. On a 12 - 16" radius shoot for around 18" radius at the bridge.