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Hi, this is my first post on here (and on any forum for that matter) so please excuse me if I have posted in the wrong section.

I am an amateur luthier working on my first guitar and I've run in to a problem cutting my own fret slots. In response to my general inability to afford Stew Mac products and my desire for a bit more customization, I have designed a jig for cutting frets accurately. Basically it is a miter box with some digital calipers in the bottom; you slide in the fretboard, set it to zero when the nut is at the saw slot, then push the fretboard through until you reach the next fret. This would allow me to make my own fretboards of any scale. However, despite simply being an extra foot or two of aluminum, I have been unable to find any calipers beyond 12 inches. Does anyone know of a site or store that sells digital calipers in the range of 24 inches or so? I tried taking apart my 8-inch set but the display only went up to 12 inches. Thanks.

I put masking tape on the fretboard and use a steel ruler to mark on the fret slots witha pencil. for regular fretboards I use a try square to get them parallel, and for fanned....... I don't!!

then I clamp a block of scrap wood on the pencil line and hold the saw tight against the scrap block.

never had a problem, never bought a mitre box!

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When I draw out my guitars full size, I usually mark each fret slot. What I do is use a 35" rule. Using the StewMac fret calculator, i start at the nut, find the whole inch position(1", 2", 3", etc.), then measure with calipers until I find the fret position. For example, on a 24.562" scale, fret number 12 is 12.281" from the nut. I measure from the nut 12", then with the calipers measure the remaining .281". You could lay down paper tape per Martin's method, use this method to mark the location on the fretboard, then cut your fret slots. Hope this helps.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Thanks guys, I think for the moment being I'll have to try one of those ideas. One thing I was concerned with when marking the fret slots is both the pencil/marker width and consequently how far removed you are from the actual edge of the caliper blade. When I tried marking it out one after another I ended up a good couple inches off of where I was supposed to be. I think marking the whole-inch marks first should help with that a lot though.

As a side note, I am still interested in seeing my jig created, so if anyone does know of longer digital calipers I would still greatly appreciate it. Just for clarity's sake, I have also attached a picture below demonstrated (very crudely I might say) the general concept of what I am thinking. There may be technical problems that I am not considering, but just from common sense it would seem to me that it would greatly speed up fret cutting and allow interesting scale lengths (not that they're necessary or advantageous, but interesting none the less). Anyway, thanks again guys.

As I understand it, the least accurate way is to measure from fret to fret. The best way is from the nut to each individual fret position. If you use a very sharp pencil, the line would end up being much less than the .023 kerf of the fret saw blade anyway. When I mark the fret positions I mark from the very tip of the caliper blade, where it comes to a point.

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Mike

The only thing nescessary for evil to thrive is for good men to do nothing.

Regular mechanic pencil graphite is 0.7mm (0.02756in), so just bigger than the standard fret saw thickness, but should be ok for marking it.

As Mike said, measuring from fret to fret can be very inaccurate, since every measurement is based on the accuracy of the one before it. So every slight miscalculation or marking is compounded for every subsequent mark. Much better to measure each from the nut. The idea to mark out all whole number inches first is wise.

I actually just found what I was looking for on Amazon (albeit at a higher price than I'd like :\ http://www.amazon.com/Industrial-Digita ... pd_cp_hi_1 ). As for now though, I'm definitely going to try the old-fashioned ruler based approach espoused above. Thanks for all your guy's help.

I haven't seen any large digital calipers, but vernier and dial calipers in larger sizes are quite common on eBay and from suppliers. If you can work in mm it will expand your shopping possibilities - look for calipers up to 600mm.

If you are careful, you can 'work your way up' the fingerboard with smaller calipers, using the slots you have cut as new 'start points' for measurement.

It's a handy idea to make a 'template stick' out of hardwood - cut the slots in it, double-check everything, and then use that as a guide for your fingerboards if you plan on cutting several this way.

Cheers
John

Filippo is correct in his comment about compounding measurement errors. I meant to work up the board in 6" or 8" 'chunks' with the smaller calipers. Checking the gaps over a span of frets will catch errors.

The wfret program by Jon Whitney will print out paper templates for fret spacing. If you glue the paper down, check for stretching.
http://www.mimf.com/library/catalog_programs.htm#exe
The program is 2.7 meg so is over the limit for upload here....

Another strategy is to buy a pre-slotted board and make a template from that...

Cheers
John