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So you think its still possible to achieve really low action and no buzz on a compound board?

If its done properly..yes

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you have to find out what the starting radius at the nut is, and what the over all end radius at the bridge is suppose to be. Thats how the bridge should be set up. and the radius of the bridge should be setup from the strings bottoms.

Dave

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you have to find out what the starting radius at the nut is, and what the over all end radius at the bridge is suppose to be. Thats how the bridge should be set up. and the radius of the bridge should be setup from the strings bottoms.

Dave

10"-16"

But you lost me. As the frets are going to be naturally lower towards the bridge than they are at the nut, I just don't understand how the action can be consistent all the way down the neck.

Evident on one of my guitars. Action on frets 1-10 is awesome, but 11-22 is to high for my liking.

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you have to find out what the starting radius at the nut is, and what the over all end radius at the bridge is suppose to be. Thats how the bridge should be set up. and the radius of the bridge should be setup from the strings bottoms.

Dave

+1

It seems a lot of folks think that if the fb is compound radiused to 12-16" that the bridge should be a 16" radius. This would only be true if the strings did not continue in a straight line after the end of the fb - I have not yet come across a stringed instrument that has managed to pull that one off! One problem may be finding commercial bridges with radii in excess of 16". I think that this is where fully adjustable bridges come into their own. Making your own bridge is always an option.

If memory serves me correctly there is a formula in Melvyn's book that shows how to work out the radius at any given point on a cone. I had a quick google for a formula but one didn't jump right up so it will have to be left to someone a bit more ambitious this morning than me.

It is obvious, but, a good setup on a cylinder shaped fb guitar will play infinitely better than a crap setup on a cone shaped fb guitar.

As a bit of a side discussion - an undersized bridge should lead to a compound radiused board having a higher required action for the outer strings at the lower frets. We know that the strings will vibrate through a greater elipse towards their centers, making the area of the 17th-19th frets require the highest action on the fretboard. With a good cone shaped fingerboard, your minimum action at these frets (as low as possible without buzzing whilst played in the owner's style of playing) would be distance 'x' above the frets. Because this is measured from a point that is higher than a cylindrical shape.

Because we have fixed the action at the 17th fret (say) and the bridge, by definition, is a fixed point, the only way to keep the string straight is to raise the action lower up the neck. I know we're only talking about .00x" or .0xmm, but this is how we tend to measure these gaps anyway and the whole purpose for putting in the extra work to get a compound radius fb in the first place.

That's enough for one day.

Second cup of coffee's just kicked in, gotta go!

Buter

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So you think its still possible to achieve really low action and no buzz on a compound board?

Definitly. I used compounds on a few JS stlyed wood porn-guitars I built for a local dealership. There was barley enough room to get a business card under the first 2 frets, Held the card there. At the 20th fret the action was about 2.5mm. Its all about the set up & the contidtion of your neck, board & frets.

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Considering the purpose of a compound radius, to a degree, is to get lower action without buzz - yes, you can expect them to work fine.

The guitars you've mentioned were most likely set up poorly.

But you lost me. As the frets are going to be naturally lower towards the bridge than they are at the nut, I just don't understand how the action can be consistent all the way down the neck.

Evident on one of my guitars. Action on frets 1-10 is awesome, but 11-22 is to high for my liking.

I don't know what you mean by the frets being lower toward the bridge. With a compound radius, your frets get flatter toward the bridge - but your bridge should be even flatter still. When you measure the action of each string at the 12th fret (or whichever fret you prefer) you should find that they are consistent, or match the radius of the fret (unless you have the bass side higher), and measured higher up the neck - they should still match the radius of the fret. That's how you know the bridge is adjusted to the proper radius.

Considering your second comment, your action has got to get higher toward the bridge to give the strings room to vibrate, that's the case with any fretboard shape. You can't expect the same action all the way down the board. I don't know if that's what you're talking about or not.

If your neck is adjusted properly, and your frets are level - you should be able to go at least as low without buzz on a compound radius board as a cylindrical one. Lower actually.

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if your board is a 12 - 16 compound Radi, the radi doesn't stop changing at the end of the finger board it continues to the bridge in this case most likely a 20" at the bridge thats what you need to make the bridge raduis at.

All the frets are the same height.

Dave

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if your board is a 12 - 16 compound Radi, the radi doesn't stop changing at the end of the finger board it continues to the bridge in this case most likely a 20" at the bridge thats what you need to make the bridge raduis at.

All the frets are the same height.

Dave

Wait, so a 10-16 board should have a 10" bridge radius? or a 16"? You and Buter seem to have said opposite things..

Sorry if these questions are retarded

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Wait, so a 10-16 board should have a 10" bridge radius? or a 16"? You and Buter seem to have said opposite things..

Sorry if these questions are retarded

Find the math formula to get the exact number, but a 10-16 board, 25.5 scale, is going to put your saddle radius around 18"

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What they both are saying is a 12-16 compound will have a 12" radius at the nut, a 16" radius at the bridge end of the fret board and will need the actual bridge to be radiused at roughly 20".

SR

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if your board is a 12 - 16 compound Radi, the radi doesn't stop changing at the end of the finger board it continues to the bridge in this case most likely a 20" at the bridge thats what you need to make the bridge raduis at.

All the frets are the same height.

Dave

Wait, so a 10-16 board should have a 10" bridge radius? or a 16"? You and Buter seem to have said opposite things..

Sorry if these questions are retarded

I don't think they said opposite things at all, it just seems you aren't reading very carefully. No offense.

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I don't think they said opposite things at all, it just seems you aren't reading very carefully. No offense.

I just saw where I misread.

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Correct me if I'm wrong (never done compound radius), but as I understand it, a 10" - 16" radius, for example, would be 10" at the nut (duh), and 16" at the *bridge.* Not at the last fret. At least that's the way I'd do it.

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For example, when Warmoth lists a 10-16 neck, they're talking about the radii on that fret-board, not anything beyond the fret-board, but I personally think the 10-16 has too much difference between the 2 ends of the neck. I think 10-14 makes more sense on the neck, considering how much wider an average neck gets at the body end from the width at the nut end.

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If Warmoth lists the radius of the last fret, say 10"-16" as an extreme example, what TOM (or any non-adjustable saddle bridge for that matter, like a Floyd, etc...) could you possibly use if you needed to?

Actually, thinking it through, both the scale length and the number of frets would also change the bridge radius in this scenario.

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Floyd needs shims (pretty much no matter what, anyway). As for the TOM, google popped this up as one of the first :

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Floyd needs shims (pretty much no matter what, anyway).

What do you mean?

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To really tweak the radius to being perfect, most of the saddles need shims put under them. I've yet to have my hands on one out of the box that was good enough to leave alone. PITA. Tedious work using under the strings radius gauges, removing saddles, adding shims, restringing, rechecking, most certainly repeating the process of adding shims again, rechecking.

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