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Look up the one Grumpy posted a couple years back. That's the one I'll build when I get around to it.

How about the jig that Todd drew? I don't think it's his design but he drew it.

It works great IMO, just have to touch up with a sanding block when done.

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Hi Filippo, This is the one I use. The only modification I have done since is to put some extra strips along the side of the fretboard blank and screws at the end (not through the fretboard, just as stoppers) to hold it nice and secure. It saves me heaps of time. I also now use a 10mm router bit.

viewtopic.php?f=10117&t=39700

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Martin Taylor
http://martintaylorguitars.com.au

I've used that jig since Todd showed it on the MIMF 7 or 8 years ago. If you only do a straight radius it works great. Use a box core bit with the rounded corners, 1/2 " shank and climb cuts. That pretty much eliminates chip out. I love mine. Still using it Todd?

Martin's jig is very cool.

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

so with these router jigs is it best to work from the outside of the FB, to the center crown? or just hog out the center down the line, and worry about the edges last? or edges first, center last? i like the concept but i generally hate routers and i am certainly not exactly a mass producer...

On my jig I start in the middle and work my way out. I do passes in one direction only (towards myself) as I found it hard to control otherwise. I find that once I am done with the first passes I can go back and forth to get any bits I have missed. Also, slower is better, you get less marks to finish with sanding. I do use the stewmac 12" radius sanding beam while the fretboard is still in the jig as it is fairly stable and i can get one done from square blank to finished fretboard (sanded down to 1200 grit) in about 15 minutes. I am usually using Australian Mulga wood or Australian Gidgee for my fretboards and they are both really hard (and can be a little brittle) so the slower passes reduce chip outs.

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Martin Taylor
http://martintaylorguitars.com.au

Do you have an edge sander that's long enough? If, so, I have a simple jig for you.

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http://www.chassonguitars.com

I've got Tracy's jig for the drum sander. It works well, but you're limited to the templates he's got. I suspect they'd be kind of tough to make well on your own. I think he'll make anything you want, but that's harder and slower than whipping it out yourself.

As soon as I figure out where I can put an edge sander, I'm doing it the grizzly way. That just makes sense. Fast, flat, adjustable...

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Mike Lindstrom

Kent, I have access to a long edge sander and would love to see that jig.

Cheers,

Shane

I work from the outside in & climb cut which reduces the chance of blowing out a chunk.


I learned about it here, on the OLF, and IIRC you made a replying comment about how you just use sanding blocks.

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Thanks for re-posting your jig Martin, I think I will build one.
I built a paddle-board jig a while back and don't like it.
Question: doesn't the protrusion of the bit below the radius line of the jig reduce the effective radius?
If it protrudes 1/2" wouldn't the effective radius be 11 1/2"?

Great tip on the core box bit in the associated thread - I gonna get me one of those as well....

Rob

Just get more 80 grit sand paper

Check the specs on the drawing & you'll see that the radius of the surfaces that ride against each other are larger than the target radius.

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I start in the middle too. barely graze the fretboard and work out. I always do climb cuts, especially important at the edge of the fretboard so you don't chip out around the slots. I pulled out a whole hunk of fretboard once on the edge with a conventional bit going the wrong way. The box core bit seems to make things a lot safer.

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

This is correct for the Martin Taylor jig. I had exactly the same thought. The radius is reduced by the amount that the router bit protrudes.

Shane, here's what I do.

This contraption first gets bolted to the table. Notice the aluminum rails that almost touch the belt. The radius guides track against those. The two levels of slots just give you two different areas of the belt to work on.



The fingerboard mounts here with double stick tape. You can make different guides for different radii. Cylindrical or compound works. I made them depth adjustable. The locking bolts on each end slide into the slots on the fence to support the work and keep it parallel to the table while allowing it to pivot. After the depth is adjusted, just sand and pivot until the guides touch the rails.



I also added a micro adjust on the fence. A nice feature.




Here's the whole thing (before I added the micro-adjust) Hope this helps.

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http://www.chassonguitars.com

Hi Rob,

Yes, that's another adjustment I have made. The bit protrudes approx. 1/4" below the radius so it does create an 11 3/4" radius. I have found that the sanding process takes care of that pretty quickly.

Martin

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Martin Taylor
http://martintaylorguitars.com.au

This is a little pedantic, but here goes anyway:

Martin, your jig clearly works well, and is producing nicely curved boards, but they're not truly radiused, straight off the jig. I don't know what the curve is (not that it actually matters) but to get a true radius you need a shipwright's compass (long compass in some parts of the world) arrangement. So instead of the bottom of the router carriage being curved, it comprises two straight lines, apex of the "triangle" at the bit position. That arrangement, with the straight bearing surfaces, definitely produces circular arcs, so, by default, a curved bearing surface must produce some other curve.

The difference between a circular arc and what you have will be quite small and if you're finishing up using radiused sanding blocks you'll end up with a true radius anyway. If you invert the curvature (or straights) on the base of the router jig you can make your own "radius" sanding blocks.

Anyone making one of these jigs (I have a similar one that does compound radius fretboards) can make the construction easier (and have true radii) by using straights instead of a curve on the base. For those in doubt, Google shipwright's compass or long compass for the geometry (also in the book).

As I said, not that it matters, but just so you know...

There's an interesting discussion on the forum here about compound radius boards and how I and others go about making them.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

I found this ingenious fretboard radiusing jig on YouTube. Seems very easy to make standard radius and compound radius fretboards by simply changing the ends. I also like that you aren't wielding a router around, instead, here you use the router table. I've made this jig, but I haven't radiused a fretboard with it yet - I've been so busy on other parts of the 3 guitars I'm currently building. Hope this gives you another idea

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Rob Flindall
Flindall Guitars
http://www.flindallguitars.com
https://www.facebook.com/FlindallGuitars

Thanks for the confirmation Anthony and Todd, just wanted to make sure I was thinking correctly, that for the Martin Taylor jig the radius on the jig has to be increased by the bit protrusion, vs the 12" radius noted on the plan.
Agreed Todd, will draw a full scale to get it just right.

Rob

dang, that guy takes his PPE seriously

Kent, that is a great jig! I have the same edge sander and will be making your jig for sure. I also really dig the neck shaft jig on your site. I like simplicity.

Sent from my DROID RAZR using Tapatalk 2

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jw ( o)===:::

I have a jig that I made a few years ago that is very similar to the one from Luthier Suppliers for the thickness sander. It works very well for me, but it`s dedicated to only one setup (16" to 25").
I figured that someone would come up with a better version of what I started with, and by golly, it happened.
No need to fear it, and if you study it a bit, you`ll understand how the principle works and should be able to change the radii at each end to suit your needs.
Also, light passes aid in getting it near perfect before a light hand sanding (or even scraping), inlays included, providing you inlay deep enough.

Coe Franklin

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

That is awesome! I am working on a pho powered cyborg radius cutter. Has anyone tried using a 1/2" down cut spiral bit?

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Pat

i have the Luthier Cool Tools plan and just haven't gotten around to building it. I do like that jig you posted from luthiers supply. Seems actually easier then the other jig....Mike

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Another day, another dollar.