Compound radius and bridge compatibility

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dren68
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Compound radius and bridge compatibility

Post by dren68 » Sat Jan 12, 2019 6:11 pm

I'm about to start a new project with a TOM bridge, and I was thinking about getting a neck with a 9.5" - 12" compound radius. Would a TOM with a 12" radius work with this? Do you just go with the last measurement in the radius to find a compatible bridge? I'm a little unsure.

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timtam
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Re: Compound radius and bridge compatibility

Post by timtam » Sat Jan 12, 2019 6:55 pm

A compound radius fretboard is effectively a section of a cone. So the radius that the strings will follow doesn't stop flattening at the last fret .. it is still getting flatter at the bridge saddles (like the surface of a cone further from the top).

You can calculate what the bridge radius should be for any known bridge position (scale length) using formulas 1 and 2 here ...
https://www.stewmac.com/How-To/Online_R ... ained.html

More (simpler) hints here for the less mathematically-inclined ;) ...
https://hazeguitars.com/blog/compound-radius-setup

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andy_tchp
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Re: Compound radius and bridge compatibility

Post by andy_tchp » Sat Jan 12, 2019 8:49 pm

A TOM can be cut to any radius you wish in a few minutes with suitable files. (Nut files are good.)
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dren68
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Re: Compound radius and bridge compatibility

Post by dren68 » Sun Jan 13, 2019 6:16 am

timtam wrote:
Sat Jan 12, 2019 6:55 pm
A compound radius fretboard is effectively a section of a cone. So the radius that the strings will follow doesn't stop flattening at the last fret .. it is still getting flatter at the bridge saddles (like the surface of a cone further from the top).

You can calculate what the bridge radius should be for any known bridge position (scale length) using formulas 1 and 2 here ...
https://www.stewmac.com/How-To/Online_R ... ained.html

More (simpler) hints here for the less mathematically-inclined ;) ...
https://hazeguitars.com/blog/compound-radius-setup
Cool, thanks for the info and links. I had no idea it was so complicated. Math is hard. :derp:

andy_tchp wrote:
Sat Jan 12, 2019 8:49 pm
A TOM can be cut to any radius you wish in a few minutes with suitable files. (Nut files are good.)
Oh yeah, I totally forgot about that for a minute. I guess I was just wondering if I could use a stock TOM with a 12" radius, but it sounds like the answer is no. Gotoh makes a TOM with adjustable saddles, so that would be an option.

Now I just have to decide whether or not I want to go with a compound or flat radius. I like the idea of a compound radius. I just wish there was a way to try it out before spending the money on a neck that I may or may not like.

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Re: Compound radius and bridge compatibility

Post by wproffitt » Mon Jan 14, 2019 8:16 am

[quote=dren68 post_id=1539823 time=1547388961 user_id=6553

Now I just have to decide whether or not I want to go with a compound or flat radius. I like the idea of a compound radius. I just wish there was a way to try it out before spending the money on a neck that I may or may not like.
[/quote]

For me, the compound radius thing (in my case, 7.25-9.5) has been great. Barre chords are even easier down low on the neck and so is lead type stuff past the 7th fret zone. I forgot about the fact that the radius keeps changing as you approach the bridge and, like an idiot, ordered one pre-radiused for 9.5. The effect is that getting the whole bridge down to my desired level of action means there’s som buzzing. You are wise to be asking questions about all of this BEFORE you buy a bridge! :shifty:

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wproffitt
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Re: Compound radius and bridge compatibility

Post by wproffitt » Mon Jan 14, 2019 8:16 am

wproffitt wrote:
Mon Jan 14, 2019 8:16 am
[quote=dren68 post_id=1539823 time=1547388961 user_id=6553

Now I just have to decide whether or not I want to go with a compound or flat radius. I like the idea of a compound radius. I just wish there was a way to try it out before spending the money on a neck that I may or may not like.
For me, the compound radius thing (in my case, 7.25-9.5) has been great. Barre chords are even easier down low on the neck and so is lead type stuff past the 7th fret zone. I forgot about the fact that the radius keeps changing as you approach the bridge and, like an idiot, ordered one pre-radiused for 9.5. The effect is that getting the whole bridge down to my desired level of action means there’s som buzzing. You are wise to be asking questions about all of this BEFORE you buy a bridge! :)
[/quote]

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rank
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Re: Compound radius and bridge compatibility

Post by rank » Tue Jan 15, 2019 3:56 am

timtam wrote:
Sat Jan 12, 2019 6:55 pm
A compound radius fretboard is effectively a section of a cone. So the radius that the strings will follow doesn't stop flattening at the last fret .. it is still getting flatter at the bridge saddles (like the surface of a cone further from the top).

You can calculate what the bridge radius should be for any known bridge position (scale length) using formulas 1 and 2 here ...
https://www.stewmac.com/How-To/Online_R ... ained.html

More (simpler) hints here for the less mathematically-inclined ;) ...
https://hazeguitars.com/blog/compound-radius-setup
Thanks for the useful info.
We are merely moving shadows-PS. 39:4-7

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