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Hello --

I'm nearing completetion on guitar 3 and I've got an intonation question. I have a Stewmac intonator and my nut is mostly filed (enough to hold the strings) -- Do I have to set the string height at the nut BEFORE I set the intonation at the saddle? I thought it didn't matter, but now I'm wondering... Also, do many of you just measure out the distance to the saddle, route the slot, rough the saddle, THEN do the intonation? Does it always work out? Many thanks. Ben

Cool. Thanks, Hesh. So do you use the "guitar string on the saddle" method to fine tune your intonation? Does anyone use the Stewmac Intonator? Any thoughts? Thanks.

Ben

the intonator is used to locate the saddle slot location, including its angle. but once the slot is located and cut, further adjustments to the intonation are done by adjustment of the string break location on the saddle. a 1/8" saddle makes this easier. one method of doing this is to form the saddle's top radius at its finished height, leaving the top surface flat. then using a short length of treble e sting on top of the saddle under each string in turn, mark the string break points and form the top surface of the saddle accordingly.

I use the theoretical scale length+.100" at the center of the neck to the face of a 1/8" saddle. With the normal saddle angle this gets me close. I then set my action, then use the method that Michael describes to fine tune.

Al

I use the S.M. intonator every time...without exception. I have to because I never pre-cut my saddle slots on my bridges. Also, If I am retro-fitting/installing BFTS on the guitar I have filled the old bridge slot and need to know where to re-slot. Before the Stew Mac invention you had to make a "false saddle" and move it around to find the "best" spot(s).
After I cut the slot for the saddle, I put a level uncut saddle in the bridge and check the intonation with my strobe. I then file the saddle top to get the intonation where I need it. I check to see exactly where the string is coming off the saddle by slipping a piece of paper ( usually the string wrapper)under the string and between the saddle. You can get a good feel for how much filing you need to do that way. Often the string looks like it's coming off at a certain spot but is forward or aft...so the paper trick helps ( got that from Greg Back). I use a thicker saddle so I don't usually have to build a shelf on (there is a pic of my "shelf" somewhere in the archives) Frank Ford has a formula for figuring how much movement is needed per cent based on scale length( see his site...it's great!). I can eyeball it and get it pretty close but it often takes a few trys to get it perfect ( if there is such a thing). As far as the nut goes... you definitely want to have it as close as possible to it's final height. It does affect how sharp those first three frets (or so) play (especially the first three)when the strings are depressed.Dave-SKG38950.4127662037

_________________
Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"