Compound Radius Set up question

[TheWoodShed]

When doing a set up to generally match the radius of the fret board on the bass, on a compound board what radius do you match for the bridge?

[TheWoodShed]

Gotta love posting from my Droid. Please delete. Duplicate post.

[allexcosta]

You follow the geometry of a cone. The formula is here:

STEWMAC.COM : Compound Radius: Explained Free information

For a standard 9.5-16 the bridge will be around 20...

[Bob C]

The flat, cylinder and cone diagrams are very well explained. The radius formula diagrams - not so much.


This article does clearly point out to me the benefits of compound radius for an even setup (when using anything other that a flat fingerboard OR angled strings).

The big question is: Why aren't compound radii more common?

[TheWoodShed]

Originally Posted by allexcosta

You follow the geometry of a cone. The formula is here:

STEWMAC.COM : Compound Radius: Explained Free information

the bridge will be around 20...

What do you mean "For a standard 9.5-16"? Where are those measurements taken? At the nut and 17" point of a 34" scale bass?

[TheWoodShed]

Originally Posted by Bob C

The flat, cylinder and cone diagrams are very well explained. The radius formula diagrams - not so much.


This article does clearly point out to me the benefits of compound radius for an even setup (when using anything other that a flat fingerboard OT angled strings).

The big question is: Why aren't compound radii more common?

Exactly. I am thoroughly confused.

[Bob C]

The WoodShed,

To answer your original question, here's how I set up my action: As a starting point, set all strings the same height at the last fret. Then tweak it by feel from there.

My bass doesn't have a compound radius. But the same principle applies. You can only have your strings set at one curve. That is, unless you are considering the radius of the nut. That's another can of worms, I suppose.

[walterw]

Originally Posted by Bob C

As a starting point, set all strings the same height at the last fret.

here's your answer.

don't bother trying to caculate or measure a "radius" at the bridge; even with a non-compound board, the strings are still starting from a narrow spread at the nut, going to a wide spread at the bridge.

use your little machinist's ruler to set each string to be the same height off of one higher fret (for me it's 3/32" at the 15th). this will let the string path automatically follow the fretboard, compound radius or not.

from there, you can indeed adjust by feel; i like them a little lower, especially on the treble side. i might end up with something like 'just over 2/32" on the treble side', gradually increasing to 'just under 3/32" on the bass side'.

as long as the measurement is the same or is consistently increasing from string to string at a given fret, you'll conform to any radius just fine.