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I'm planning to make a new saddle slotting jig (probably based on the pictures I've seen of Todd Stock's). But I got to thinking. If you cut your saddle slot off the guitar, do you do that before the bottom is shaped to match your dome? Do you done it after slotting? Either way, do you find that after final shaping and gluing and such that the bottom of your saddle slot is no longer flat? I guess the bridge is pretty stiff compared to the rest of the top.

Thanks,

Mike

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Mike Lindstrom

The best way with a simple angle jig is to slot and drill while in the rectangle. Make sure you are square , then once slotted and drilled make the bridge.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Mike, I glue flat bridges to 15' arched tops and they do conform to the top. I rout the saddle slot after gluing, then, after stringing, insert a jack under the saddle inside the guitar and re-rout the slot flat.

Me too, except for the 15" arched top part.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

I thickness the blank, route the slot, taper the blank by planing from the back (thickest forward of the saddle slot where it needs strength, thinner behind to reduce weight, and angle the saddle slot back a tiny bit to compensate for the bridge rotating under tension), scrape an arch into the bottom of the blank (easier before cutting out the shape, as it's hard to get a smooth curve right to the tips of the wings later), and then cut out the shape.

Interesting thought about the saddle slot losing its flatness... I never really thought about it, and I'm not sure how to check it either. Maybe chalk on the bottom of the saddle, string it up, and then take it out and look in the saddle slot? But my bridges are more or less rigid across their full width, and arched to match the top closely, so it shouldn't flex too much. I hope. Because routers around finished guitars make me uncomfortable.

I slot mine while still a rectangular flat bottomed blank on my milling machine. I also cut the half-round slot for a Highlander UST, if applicable, at the same time using the same set-up (different cutter) to ensure accurate depth and perfectly centered. The Highlanders are very sensitive to this, but if installed correctly are my preferred UST.
-C

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Freeborn Guitars
and home of BeauGuard©

Thanks for the replies. Now I've got to wondering if a flat bottom in really necessary. Has anyone experimented with a slight concavity to the saddle slot or the saddle itself? Sort of like a sprung joint on a tabletop... I can imagine that having a good solid base on either end is far more desirable than having a wobble point in the middle. Everything you read talks about needing a flat saddle slot with good contact, but lots of instruments support the strings just on either end of the saddle / bridge.

I guess I better get busy finishing this box so I can arch a saddle and see what happens. If only we could get some moisture in the air, or it'd get cold enough that my furnace humidifier could run.

Mike

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Mike Lindstrom

I don't know how your plan will work out Mike, but I suggest you keep the bottom of the slot straight and scoop out the middle part of the saddle. If the results are less than satisfactory, it is easy to make a new saddle, the curved (or stepped?) saddle slot bottom sounds like more work, both to make and undo.

I don't know if you had planned on using one, but as Chas says, UST's are very sensitive to even pressure on the saddle, some more than others, but I don't think any would work with a saddle such as the one you suggest. In fact, one trick to improve contact between the saddle and the element (or bottom of the saddle slot) is to saw kerfs in the saddle, one between each string, from the bottom to just below the edge of the slot. This makes the saddle more flexible, so it will conform better to the geometry below it, and it can help fix uneven string signals, which can plague certain UST's.

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Rian Gitar og Mandolin

Arnt- I had the same thought. I figured scooped would be better than stepped because a scooped joint might flex to make a good joint, while stepped would at best make a three point contact. Like you, I also couldn't think of a good way to make a smooth curve in the bottom of the slot. And of course, when it is a miserable failure, replacing the saddle is a easier and cheaper.

I've never used a pickup, but I have read enough here to know about the problems people have with getting good contact. I never heard about the kerfed saddle though. Cool idea. Does anyone kerf their saddles routinely?

Mike

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Mike Lindstrom