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I was asking Fred about his fan fret and he suggested another thread for this. Couldn't agree more. I'm not terribly interested in the why, but more in the how. Are there templates for slotting? Rules of thumb for bridge placement? Is intonation tricky?

Mike

I've only done one multi scale, but it was much simpler than I thought it would be. I just laid out one scale on the treble side of the board, and another on the bass side and connected the marks. I slid them up and down, making a few different layouts until I got one that looked cool. Mine was a 27-29 baritone with the perpendicular fret around 5-6. People who really play, liked it. I found it tough down on the first few frets where I live. If I had shifted it to keep the lower frets easier to play it would have required a much more drastic change to keep the braces under the wings of the bridge.

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Mike Lindstrom

Yep, it's really pretty easy, although there are plenty of fine points to discuss.

I slot the board by hand. Mark the fret positions along the lines of the low E and high E strings (not the edge of the board), and clamp a squared up wood block to the board to use as a saw guide, connecting the dots. Include marks for a zero fret and cut all the way through the board there, to cancel out any slight offset of the saw relative to the marks. You can slot after tapering the board this way, which can reduce waste in some cases

The neck width affects the "intensity" of the fan for a given scale difference. So if you want to do large scale differentials (like Mike's 27-29" baritone) a wider nut and bridge spacing can make it more comfortable. And note that if you put the perpendicular fret at 12, the nut will be more intensely angled than the bridge, because of the taper. I'd recommend around 7th to 9th fret perpendicular, and to avoid huge scale differentials.

To position the bridge, I use the compensation numbers from the StewMac fret calculator (low E from the longer scale, high E from the shorter scale) with a ruler laid along the string paths.

The bridge angle affects tone to some extent, because it causes you to pluck the low strings proportionally closer to the center and high strings proportionally closer to the bridge than normal, all things equal. Bruce Sexauer does very subtle fan frets, sometimes with the bridge as the perpendicular "fret" for this reason. Here's a thread with lots of discussion, where he explained the rationale http://www.acousticguitarforum.com/forums/showthread.php?t=325150

The angled frets also affect string bending. "Pull" bends work better at the lower fret positions, and "push" bends in the upper positions. So keep that in mind when considering how much string-to-edge space you want.

Bracing, IMO, should be as close to normal as you can get it while still getting good bridge-X overlap. Try to keep the X intersection at the center line, rather than offsetting it to the treble side too much. Twist the bridge to cancel out some of the angle. Treble wing tilted downward, bass wing tilted upward. The standard steel string bridge is already twisted in a sense, with the angled saddle slot

I also like to do asymmetrical body shapes to follow the bridge angle better. "Pinch" the treble side and "expand" the bass side, so the treble side X leg isn't so much longer. Here's a harp guitar, but regular should be somewhat similar (especially if you move the bridge up to 14 fret position so it doesn't need to be so wide to reach the X legs). Note, however, that dragging the bass side waist downward with the asymmetrical shape was a mistake... the waist should remain perpendicular to the center line for maximum comfort.

Very cool Dennis; you are the "harp guitar man". Mike, thanks for asking the question; as I said in Fred's thread, I find the look of the fan frets appealing. Hope there are more replies with pictures.

I use fretfind (search the web) for laying out the frets .. I put the numbers in as if to make a lefty, then the frets are printed out backwards, and I glue that to the rear of the fingerboard blank, already tapered. Then using a sled with a hairline, I slot on the tablesaw. As mentioned above, using the 7th or 9th fret as the reference fret as I call it seems to work best for most layouts. Or depending what you are trying to do, you can make other points the reference, as I do on my harps. I wanted the bridge to angle more for aesthetics, so I made the nut straight, using a 1/2 inch delta ... pix on my website .... as for bracings, you can make the tilt of the X lessen by making bridges with more slant to the saddle slot, thus less slant to the bridge when you put it on.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I cheated on the 2 I have built, I purchased a 27 25 scale CNC cut FB from Bryan Galloup and the 26/25 for the Cocobolo guitar from Andy Birko. I had plans to cut the second one myself but got into a discussion with Andy when he was preparing the layout program for fan frets and decided to give him a chance to try it out. He did a great job and Paul Murphy and I had a fun visit to Andy's shop. Andy's program generates a drawing of the layout from nut to saddle and it came in handy as a reference when laying out my drawing for the guitar. I actually always cut my fingerboards but after getting this one done it is almost not worth the bother setting up to cut one in house as I will probably not make very many fan frets.

The only thing different from a normal build is the angles of the bridge/bridge plate and nut. The 1" spread requires very little rotation of the X brace but the 2" spread required much more modification of the bracing. The whole thing probably only adds a few hours to the build but once the layout is established a second one will go quite a bit quicker.

Andy watching my FB getting cut.



Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Oh, and one more thing I just remembered is how to deal with the angled nut.

The way I do it is to start with the headstock extra thick, but otherwise cut to my usual ~15 degrees, scarf joint cut and glued square just like normal. Then go at it with a block plane on the treble side, removing material until the nut line is angled correctly, and the whole surface is flat. Effectively "rolling" the headstock plane to the right. Then flip it over and chisel it down to thickness from the back.

Dennis, amazing picture. Thanks. With all the complexity of Harp Guitars, off-center center lines etc, amazing that you would consider a fan fret for one. What scales are you using? And is yours a 12 or 14 fret? The 12 is the most original, but I don't like it. I've got a body sitting in my shop that I am considering changing to a 14 fret if I can find enough bridge plate.

Yeah, it's 12 fret (where the harp arm meets the neck), with low profile heel so you can play bar chords at the 12th fret easily. Neck scale is 24.75" to 25.5", and then the 7 harp strings increase to 36" from there.

12 fret all the way for me. The elegance of being the center of the string, putting the bridge in what feels like a better place, reducing overall instrument length and neck-heaviness, which allows reducing the box weight and therefore overall heaviness without compromising balance... and with the cutaway and low profile heel, you get about the same reach as most 14 fret cutaways with big fat heels. I do like 14 fret non-cutaways though, for having both visual symmetry and decent reach... but no fan frets on those