Shim or not to shim a Lockmeister 6 on an 12-16" compound radius neck?

[Guitar Gene]

Hi, the Charvel Pro Mod So-Cal style 1 has a 12-16" compound radius neck.

I have replaced the Floyd Rose 1000 with a Schaller Lockmeister 6. It comes shimmed for a 12" radius and when you remove the shim you get 16". But here is the thing................what do you do when you have a compound radius which is 12-16?

After rebuilding the guitar after modding I discovered I could not set the action as low as I would like due to fret buzz in several places. I have set up A LOT of guitars and this was the first time this happened during a setup for me. I began to wonder if it was because I removed the shim but decided to check the frets.

I discovered about 14 high spots.

I decided to give it a full fret level and polish which I did. This is probably why I could not get the action as low as I wanted BUT it COULD possibly STILL be the fact I removed the shim. You notice things like fret high spots when you attempt to set the action low as opposed to high more often.

So, my question to you all is this:

On a compound radius neck which is 12-16" if you have a trem which can be set to either 12 OR 16" ------------------------------------------ what do you do??

I am about to rebuild the trem and set the intonation, height etc again and I thought just before I do I would ask this question to see what you folks reckon.

My gut feeling is I was correct to removed the shim and go with the 16" radius, my high frets were probably the cause of my not being able to set the action as low as I wanted and it is most likely sorted now since my fret job but I will not know till I rebuild her................. and it COULD still be an issue that the shim is not helping matters.

What do you reckon?

[metalhobo]

the radius increases as you go from a nut to bridge. for a uniform radius the fretboard profile (and thus the frets themselves) are cylindrical. for a compound radius, it becomes conical. the radius increases linearly as you go from nut to bridge. if we assume the radius at the nut is 12" and at the 3/4 point (around the 24th fret) is 16", this would mean at the bridge the radius would be around 17.3".

17.3" is pretty close to 16". in terms of action, the difference in string height (at the bridge) at the apex of the radius is less than 0.003" between the two. I would set the bridge radius to 16" and forget about it.

[Guitar Gene]

the radius increases as you go from a nut to bridge. for a uniform radius the fretboard profile (and thus the frets themselves) are cylindrical. for a compound radius, it becomes conical. the radius increases linearly as you go from nut to bridge. if we assume the radius at the nut is 12" and at the 3/4 point (around the 24th fret) is 16", this would mean at the bridge the radius would be around 17.3".

17.3" is pretty close to 16". in terms of action, the difference in string height (at the bridge) at the apex of the radius is less than 0.003" between the two. I would set the bridge radius to 16" and forget about it.

Hi, thanks , I will rebuild it the way I had it so for 16".

The fret leveling job should have sorted the buzzing out. I will know tomorrow when I re-assemble the trem, re-string and intonate it and do a setup.

There were quite a few high spots on this one!

Thanks...............

[Number Of The Priest]

Here's an older thread about that. https://www.jcfonline.com/forum/equi...-saddle-radius

metalhobo, where did you obtain your saddle radius of 17.3 inches? The above thread mentions the saddle radius should be closer to 20 inches.

[Guitar Gene]

Here's an older thread about that. https://www.jcfonline.com/forum/equi...-saddle-radius

metalhobo, where did you obtain your saddle radius of 17.3 inches? The above thread mentions the saddle radius should be closer to 20 inches.

Thanks.

I will let you know how the guitar turns out.

[metalhobo]

Here's an older thread about that. https://www.jcfonline.com/forum/equi...-saddle-radius

metalhobo, where did you obtain your saddle radius of 17.3 inches? The above thread mentions the saddle radius should be closer to 20 inches.

1. I'm assuming the fretboard profile is conical. I can't imagine j/c does something more "exotic" than this
2. I'm assuming the radius of the profile of the strings themselves are the same as the profile of the fretboard. this is not strictly true, since you should add the distance from the top of the fretboard to the strings to that radius. but this distance is usually a fraction of an inch so I'm ignoring it.
3. from assumptions 1 and 2, we know the radius increases linearly with respect to the distance from the nut. we know the radius goes from 12" at the nut to 16" at the end of the fretboard. this represents a 4" increase for 3/4 of the scale length. 4 inches divided by (3/4)=5.333. 12+5.333=17.333.

because of the approximation I made from the second assumption which underestimates the radius, it's possible that the actual radius at the bridge might be something like 17.5-18".

it's not surprising at all that a 20" gauge would read "correct" on an 18" radius... this is because over the 2.1" bridge width, those curves will seem very close. they too will only differ by a maximum of 0.003" (or 0.08 mm) over that segment. this is on the order of a hair's width.

[Number Of The Priest]

I trust your math, and I trust the math. Thanks for performing that calculation.

Following your formula, the default compound Warmoth 10-16" radius means the saddles should be set for a radius of 20". (I'm mostly adding this paragraph for my own reference since building a Warmoth guitar has been on my mind lately.)

Following your formula, a typical Suhr compound radius of 10-14" means the saddles should be set for a radius of 15.333".

You are right about how negligible those very flat radii seem from each other even when using radius gauges. I have a set that goes from 7.25" to 20" and all the gauges above 15" seem scarily similar when I'm trying to measure various fretboards of known radii on my superstrats.

[ed]

Kinda on topic. I was just disassembling an OFR and taking off the saddles off and there were sparks flying and pretty much smoke coming out of them. Just a PSA dont overtighten the saddles that is how you will strip the threads on cheaper floyds especially and those older schallers/JT-590s.

I am not sure if this was from factory or maybe this guitar got a setup at some point. The setup was ass anyways