Radius Gauges for Dummies

[Rich_S]

Another question related to my Schecter PT project.

It has a standard MIM neck, so I needed to set the string radius at the bridge for 9.5". I have a set of freebie plastic radius gauges that came in one of Dan Erlewine's books. I know the understring radius gauge is the "right" tool for setting string radius at the bridge, but the saddles sit pretty low on this guitar (no neck pocket shim) so my understring gauge won't fit between the strings and the body. So, I ended up using the normal 9.5" gauge on top of the strings.

With the strings set in this way, to my eye, they seem flatter than I'm used to on other MIM Teles. However, when I sketched the problem on paper, I came away thinking that using a standard gauge on top of the strings should end up making the actual radius smaller than the gauge's nominal curvature.

So now I'm all confused.

The goal, of course, is to match the bridge radius to that of the fretboard. If I'm forced to use a standard gauge, is the 9.5" one "close enough" or should I use one slightly larger or smaller?

I looked at Stewmac's nice stainless understring radius gauges, and I don't think they'll fit, either, so I'm stuck with measuring on top.

 

[charlie chitlin]

Turn the saddles up, check underneath, then lower them all the same # of turns.
Or just check each string with a ruler at the last fret.

 

[LutherBurger]

I capo the first fret and use a ruler to adjust each string to exactly 2mm above the 17th fret. This way, the strings follow the radius precisely.

Of course, I then tweak individual string heights until they all feel "right" to me.

 

[gwjensen]

Personally, I go by sight and feel. Use a gauge to get you in the ballpark, but don't be afraid to tweak for there until it feels right for you regardless of what the gauge says. JMO.

 

[KokoTele]

I capo the first fret and use a ruler to adjust each string to exactly 2mm above the 17th fret. This way, the strings follow the radius precisely.

Of course, I then tweak individual string heights until they all feel "right" to me.

What he said. I have a set of the radius gauges and rarely use them for setups.

Besides that, since the strings taper together, they really lie on the outside of a cone instead of the outside of a cylinder. When the frets are in good shape, you'll get the best playability when the saddles are a little flatter than the neck radius.

 

[BUILTACASTER]

No capo and 5/64" at 17th fret or where the neck meets the body. I capo the first fret to check neck relief at the 7th before adjusting string height.

 

[MagicTwanger]

Rich_S,
I made my own radius gauges, which you can make that fit under the strings. All that is needed: string, a thumbtack, a pencil, and some cardboard. Set your pencil at the radius length desired from the thumbtack and draw an arc on the cardboard. Cut out your gauge, leaving a small tab in the top/center for manipulating it under the strings.
-MT

 

[bullfrogblues]

Radius gauges are useless as far as I'm concerned. Wasted money. Measure string height like Builtacaster said, or measure at the last fret and you'll have the setup you need without the gauges.

 

[telex76]

Like some others, I have radius gauges and I don't use them for setting string height at bridge.
Set string height measuring to top of fret, if the fret is the right radius then so will be the strings.

 

[ItchyFingers]

I have a bunch of gauges I never use. I just tweak and tweak until it suits.
The only time I even measure relief is when the topic comes up in here. .004" for future reference.
I do use a quality straight edge to make sure the neck and frets are near level before tweaking though.
Edit: I DO use string gauges before a re-fret to determine what radius I am working with.
Edit: To clarify, I use them on the frets or bare board for the above mentioned determination which designates what tools I will need to use. A proper Radiused caul or a flat caul. I generally touch up the bare board with frets removed first.

 

[soulman969]

I just created my own and use them to rough in the settings and then I adjust a bit from there. Typically my setup is a little flatter than the boards radius itself.

 

[Doug 54]

Rich S:

You don't have to or necessarily need to match your 9.5" radius to exactly that on your action:

Remember, at the D & G string area those strings are at the top of the 'arc' of the radius,
and if you bend any, you can get away w/o any fretting out with a 12" or so radius.

.

 

[Rich_S]

I ended up just using my 6" steel ruler, set them all to 1/16" at the 17th with a capo on the first. It seems to play pretty well, at least for now, while it settles in.

 

[steam-powered]

Personally, I go by sight and feel. Use a gauge to get you in the ballpark, but don't be afraid to tweak for there until it feels right for you regardless of what the gauge says. JMO.

I also pay more attention to sight and feel. Looking down the neck: do I see any bow? Looking across the strings, do any clearly sit higher/lower than I would expect? Putting a capo on the first fret and fretting the low e at the last fret, then checking the distance at the 8th fret: is it touching or, conversely, clearly sit too high? Personally, I like a little relief combined with higher action than most folks prefer, so I have to rely on feel more than anything.