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Finished this up yesterday, and took it for a test drive, working real fine. $50 total plus some scraps and screws.
Saw a laminate trimmer in Aldi at $39 and remembered a plan I saved some time ago for a FB radius jig which had been shared on the OLF.
Many thanks to the originator of these, Marty McLary and to Mr Stock, who modified the plans and shared them, from which this poor imitation was derived.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I am going to take a wild guess and suggest that the subject person - if available for comment - would offer an acknowledgement of your thanks, and note that Mr. McClary is the responsible party for the design.

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For the times they are a changin'

- Bob Dylan

I really need to make one of these, can you link the plans Colin?

No longer available on the OLF I think.
PM me with your email address and I'll send, feel bad about just posting them without permission.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Stupid question: why is this jig better than a concave sanding block?

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Ever used one? Try sanding an ebony board to radius with a block and keeping it even, apart from the time and sheer sweat. Plan is to radius with this so as to absolutely minimise the sanding with the block(s)

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I don't think it is a stupid question. But I also think that the answers aren't stupid, either.

Some folks want to arch the fingerboard before it is glued onto the neck. This jig does that.

Some folks would rather arch their fingerboards with the help of power tools instead of hand tools. This jig helps with that.

In the past I have arched the fingerboard before gluing it onto the neck, but I now favor gluing a flat fingerboard onto the neck, and getting the neck attached to the body, before I arch the fingerboard. This jig would not help me with that. But if you like arching earlier in the process, this jig gets you there.

Separate questions: whether this is the sort of jig that has the hand builder of guitars machining up like a larger manufacturer (i.e., for high volume), and whether that is overall more or less productive for the hand builder. I think that really depends on a lot of factors. For me, and my way of building, I have come to believe that a fingerboard arching jig doesn't help my productivity. But others can reasonably come to different conclusions, based on how they build.

I have not used a jig on either of my builds. It looks pretty slick.

Big thank you to Don for explaining pros/cons to a newbie.

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I've used a sanding block but it's slow and boring. Especially on African Blackwood which I can't get the hang of planing either.

Avoiding tedious, hard physical labor is a really good reason for tooling up. What is tedious or hard is subjective, though. I don't mind the hand work that goes into fingerboards, but I HATE driving the bus to profile rims, so I build a motorized dish sander. I abandoned my efforts to build the perfect compound fingerboard radiusing jig, because I realized I can get there quicker with hand tools, and I don't mind the work. To each her/his own.

By a very odd coincidence, I just so happen to have the plans available as well as permission to post them. A note to Mr. McClary would not be out of place re: a nicely designed jig. Here you go:

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For the times they are a changin'

- Bob Dylan

Mr. McClary duly thanked.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I have used that jig for 13-14 years and it works just fine. Chip out on the fret edges can be avoided to a large degree by using climb cuts and using a core box style router bit with rounded edges, flat bottom and a 1/2” shank. You may still get a little minor chipping.

I made two carriages, one for a 16” radius and one for a 12” for archtops.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I've ordered a core box style router bit with rounded edges, flat bottom, thanks for the heads up.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Retired for a while now, building guitars is all about the process. After 8 instruments I find I have built a couple of jigs I didn't need, and usually end up building one more with each guitar. Nothing quite so satisfying as hand planing a nice piece of wood. And it is really fun to get those short little shavings that are broken by the fret slots.

Ed

I'd love to be able to plane my abw boards! Maybe more timbre needs to be spent fettling my old planes.

I'd love to be able to plane my abw boards! Maybe more timbre needs to be spent fettling my old planes.

I just became aware of this thread today. I designed this jig in the late 1980's if I remember correctly. I had changed a bandsaw blade and noticed the table trunnions for tilting the table and a light bulb went off. I came up with the simple design. My first jig worked fine as is and I used it all the time. After forums became a thing, I posted it on Mimf.com. That might have been maybe 20 years ago.

Todd Stock took off with the idea and posted it here. I never intended to post plans because A...plans never existed....and B. as a former teacher, I like people to do things for themselves with some help... . A picture is worth a thousand words, eh?

Well iterations of it turned up in books and online and even for sale. It's kind of funny how people will change one detail and all of a sudden it's their invention.... Anyway it is the best jig I ever designed and considering how much effort goes into radiusing a fretboard, it's a real time saver even if you only do a couple a year.

One important part that other designs don't include is some means to keep the carriage perpendicular to the centerline of the fretboard. Using a jig with just arcs on pvc can skew tool marks into your fretboard. Mine doesn't do that. Thanks again for giving me credit Woodie and Colin. Most do not. .

Always pleasure to be able to give credit where credit is due. Thank you.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

[quote="Terence Kennedy"]I have used that jig for 13-14 years and it works just fine. Chip out on the fret edges can be avoided to a large degree by using climb cuts and using a core box style router bit with rounded edges, flat bottom and a 1/2” shank. You may still get a little minor chipping.



You can avoid chipping by radiusing before you cut the fret slots. I radius, cut fret slots then taper. Works for me.

I made this Jig to radius my fretboards and it works really well, verses the other way of free hand sanding. Used some 3/4” plywood and wood screws. The channel is slightly larger than the radius block.

" I had changed a bandsaw blade and noticed the table trunnions for tilting the table and a light bulb went off."

I love how ideas come together like that!

I glue them on flat otherwise I'd probably build one of these things. For those who glue them on flat though a real good tip for speeding up the process is to just use a hand plane and hog off a lot of the wood before switching to radius blocks. I always follow that with a beam too.

Todd Stock was kind enough to share many good helpful ideas for guitar building. I miss him here.

Trivia question: What's the difference between a jig and a fixture?

Trivia question answer: A jig moves like a dancer moves while doing a jig. The plans herein include moving parts so it's a jig.
A fixture stays fixed and does not move. Yes, worthless information.

A fixture holds the part in place. A jig guides the tool and while holding the part in place. I actually took a college class in jig and fixture design as part of an Industrial Engineering class. That's about all I got out of it, other than thinking about how a tool direction hits the part.