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For a 16" radius fretboard I read somewhere that the saddle should be 20" radius. How do you do yours?

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A higher purpose for wood.
Rich Smith
Issaquah, WA

I actually a 16" radius for the saddle as well, but then it is angled to allow for lower action as you go from low E to high E

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Andy Z.
http://www.lazydogguitars.com

I do the same as Andy.

But this is an interesting idea and I can see how it would reduce the action for the middle strings.

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Ann Arbor Guitars

What matters is that the bottom of each string is at the right height to produce the desired action. your saddle can look like a saw blade if the bottom of each string is appropreate to the action height.

Michael is right on. That is why I use the 16" but angled. It makes the set up for action a piece of cake!!!
Since I have a 2/64th difference in action at the 12th fret between high and low E,(4 and 6/64ths typically) I just mark the saddle with a 4/64ths difference in height at the point of the high and low E on the saddle blank. I then use my radius curve to connect the dots. This sets up a perfect transition of action from low to high E. If I need to lower the action at all, I take a even amount off the bottom.

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Andy Z.
http://www.lazydogguitars.com

That sounds cool Andy! I believe my Taylor has a 16" radius saddle. I wonder if I could copy its saddle?

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A higher purpose for wood.
Rich Smith
Issaquah, WA

I would trust but verify.... Measure the radius on the Taylor saddle first.

Also, and related, some builders also reduce the height of their bridges about 2/64th" on the high E side transitioning smoothly from the low E side. Since the saddle will be lower on the high E side for the reasons that Andy and Michael pointed out having less bridge height on the high E side makes for a better break angle over the saddle for the high E and B strings.

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Ann Arbor Guitars

Hesh, do you have a good tip on radiusing the bridge? I bought one of the LMI Martin style bridges.

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A higher purpose for wood.
Rich Smith
Issaquah, WA

What I do is take a straight edge off the top of my frets at each string position. make a mark on the mounted saddle. I calulate the desired height of bottom of string above the phantom fret mark on the saddle and make a mark this height above the previous marks. I connect these points with a french curve and draw out this arc (not a pure radius but a fitted arc)

I then file the saddle to with in a 64th of the arc. i then proceede to intonation filing the break point as needed for intonation for each string. I then blend file a continious break over radius to the top of the saddle and double check intonation and adjust as needed.

So you see i don't see the top of the saddle as a radius. I see it as an arc defined by points determined by the desired bottom of the string heght over the phantom fret height plane.

This takes care of the sting height difference from 1st to 6th string right up front rather than creating a radisu then shaving a 2/64 slope to the botton of the saddle to drop the lower side or trying to measure how much to rotate the radius at the 6th sting contact to achive a 2 64th drop.

Rich bro yes there is a toot in the archives for fitting bridges to the dome of your guitar top.

This toot shows how that could be done, one method, and then goes into the idea of routing a slight ledge around the bridge so that the bridge sits on top of the finish a few thousandths in all around the bridge. The second part is of course optional and not required but makes of a neater install: http://luthiersforum.3element.com/forum/forum_posts.asp?TID=13497&KW=Fitting+bridges#forumTop%22

Please note too that sanding the bridge on the guitar top works best at a controlled RH and then when the guitar is finished if you try to recreate the RH, or something close, and let the box and bridge acclimate the bridge will fit like a glove.

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Ann Arbor Guitars

thanks for the tips. I probably won't rout a ledge since I've French polished the top. I have sanded like the link shows, but will do it again. We are having colder than normal weather so the RH is down around 33% so I'll check my sanding when RH returns to normal range around 45%. I like the tips on how to radius the saddle - muchas thanks & Seasons Greetings. We are due for a big storm tomorrow with high winds which likely means power outages for days - Santa can you bring me a power generator??

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A higher purpose for wood.
Rich Smith
Issaquah, WA

Good question. I use the radius gauges from StewMac to make the top of the saddle.

In theory, the saddle should have the radius that the board would have if extended as far as the saddle. If your board is single radius, then use that radius for the saddle. If it is compound, you need to figure what the radius of the cone that the board defines would be at the saddle location. But don't worry about getting the arc to decimal places. With one of my typical boards that goes from 12" at the nut to 16" around the body joint, I use a 20" saddle radius. Then as others have said, you can tilt it down toward the high E.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.