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I bought the plans for this jig from Luthiers Cool Tools. I chose to build this jig because of its small footprint and robust design and construction. The plans are clear, concise and understandable. A bill of materials is provided as well as sources for the hardware and components. I bought most of the hardware from local sources. Bearings and UHMW polypropylene were purchased from McMaster Carr and the router bit was purchased from Rockler. Included in the plans are radius templates for inserts that will produce 12”, 14”, 16”, 18”, 20”, 22”, 24” radii. The jig is capable of producing compound radii on fretboards. It is constructed from ?” Baltic birch ply for the frame and hardwood for carrier board, guide blocks and bearing mounts. The router rides in a track bordered by aluminum angle stock.



This shows the jig mounted in a bench vise ready for action.



I made a simple square router base lined with UHDMW polypropylene to allow the router to slide securely and freely within the track. I found that the round base was too easily tipped and bound as it traveled. The router bit is a 3/4" core box bit from Rockler.



This shows the FB half done. It took about 20 passes to get this far. I indexed the carrier board about 1/16" for each pass.



This is the completed board. Just a light sanding with 100 grit was all that was needed to smooth out the machine marks. I used the 1/4" setup block to adjust the bit height before starting the operation.

The jig was quite simple to build. It's very important to dimension the carrier board perfectly. It must be straight and dead flat. I chose to use 7/8" hard maple for this and had my Amish buddy joint and thickness sand it until it was just right. The results were that the first board was dimensionally uniform on from end to end.

I tested this out on a maple board initially before risking a BRW FB. So with a sample size of 1 so far, I'm happy with the results.

Thanks for looking...now fire away with questions, suggestions, comments...but please, no tomatoes!

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JJ
Napa, CA
http://www.DonohueGuitars.com

Real Slick JJ,
What hardware connects the inserts to the carrier board?
Could we get a look at under the carrier?
How do you secure the FB onto the carrier?

Thanks,
Wade

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Wade
Nashua, NH
http://www.wadefx.com

Just to make sure I'm understanding it correctly ... the router rides on a flat guide, and the fingerboard carrier is hand-held, sitting on the radiused guides on each end and then moved back and forth across the width of the fingerboard. Right?

For the sake of the next question, picture the jig in front of you with the fingerboard oriented left-right. To use it, you'd push both fingerboard sled handles away from you and toward you. What inaccuracy is introduced if the left and right handles are not perfectly in sync - that is, if one handle is further forward or back than the other?

Thanks for your help in understanding this baby!

lookin' good! I'm planning on building craog holden's jig, but if this one works well, for a much smaller footprint (my shop is tiny; 15'x7', ish), it's certainly worth considering. Craigs will have to wait until I trade up in shop size :)

Far as I can tell, its a box with radiussed inserts that slot in, with ball bearing runners (two each) running along the radii. Are the covering 'slats' at the two ends to hold down the carrier board while routing (longitudinal direction)? I've drawn up similar plans before, but its the locking down that always stopped me from building one like this. Have you tried it with a compound radius board (lets say an extreme-ish 12-20" progression, which I want to try for my electrics)? how do the bearings deal with the longitudinal diplacement involved in a compound radius? Is there much/any? Does it take fingerboard thickness (even down the edges, not down the center) into account?

Final question, comment: why a cove bit? I would think a 1/2-3/4" flat bit wold be faster and cleaner; my current rig uses a 1/4" flat bit, works well.

Good lookin jig JJ, it takes up a little less space than mine. Good call on that square pad. That was the only reservation I had about your original design.
I use a 1/2" dovetail bit in mine because it was the only carbide bit I had that had a flat bottom. It takes me about 6 to 8 passes to do a whole fretboard. It does not come out precisely smooth but a couple passes with my Stewmac leveler bar and some 220 grit finishes it off after the fingerboard is attached to the neck. John How39057.5338657407

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Tickle your guitar daily, and it'll tickle you back.

JJ JIG MASTER!

WOW very cool and slick jig JJ, WELL DONE BRO!

Here's a shot of the underside of the carrier:



The 6" carriage bolts are connected to the carrier and pass through the base thtough 2.5" slots. They are held in tension by compression springs and wing nuts and 3/16" thick x 1.25" UHMW washers ride on the bottom of the base.

Wade...The FB is secured to the carrier by 4 pieces of 1" double sticky tape. The radiused inserts slide into a slot on the sides and are just held in place by the slots.

Pete...The carrier is indexed laterally while the router travels longitudinally. By tensioning the carrier bolts securely from below and being guided laterally via the guide blocks, the carrier actually indexes fairly evenly. It's always possible to take more passes than I did but it seemed to work well during my first trial.

Mattia... haven't tried a compound radius yet. The rounded bit works better for a radius than a flat bit, so I was told. I have, however, used a flat 1/2" bit to thickness a board...you just have to substitute 0 radius blocks for the bearings to ride upon. The flat bottomed bit works fine for that.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Very slick jig. Thanks for the pics and info!

It sounds like you do a pass with the router, then move the FB and carrier 1/16 or so , then do another pass with the router. Is this correct?
Being cheap, and liking to keep things simple, I was wondering if the bearings were really necessary. Do you see any problem with just resting the carrier on the radius blocks?

Thanks
John

Here's another shot that might further clarify what's going on:

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JJ
Napa, CA
http://www.DonohueGuitars.com

That looks great JJ! Hmmm... could there be another jig in my near future!?

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

I like it a lot JJ.It would be perfect for my small shop also. Thanks for posting this.

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Anderson Guitars
Clearwater,Fl. 33755

Chris...perhaps I didn't describe this clearly. The carrier is indexed 1/16" and then you take your hands off it. You then put your hands on the router and move it lengthwise. It's not necessary to have hands on both components at the same time.

The Holden device is superb and you would never go wrong having one. I chose to build this one rather than buy the Holden. I also liked the smaller footprint of this one due to my limited space.

I've now done the 2nd fretboard...this one was pre-tapered and it worked as well as the first which was straight. I doubled the number of passes this time and just had to kiss it to sand off the milling marks.

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JJ
Napa, CA
http://www.DonohueGuitars.com

That clears it up a lot!

I like it.
It is good.

Thanks JJ!

Wade

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Wade
Nashua, NH
http://www.wadefx.com

JJ -- great jig! Being extremely space limited myself, I sure appreciate how small a footprint this one needs.

Hesh...Im not that brave...that's why I did trials with a maple board first. I've done 3 BRW boards now and they all turned out well.

Terry...I believe a rounded bit would help to prevent chipout...not as much wood getting whacked with each pass...but you have to take a lot more passes. More importantly, I'd radius straight boards instead of the tapered boards. I tried both and prefer the straight.

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JJ
Napa, CA
http://www.DonohueGuitars.com

John...I believe this could be made to work without the bearings...but not as smoothly. I got the 4 bearings at McMaster-Carr for around $3-$4 each...not really that costly. My recommendation...splurge on the bearings.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Thanks JJ. I have been looking for a good simple jig to do compound radii. This looks like the ticket! I emailed Rick Micheletti (he builds great looking guitars by the way, haven't heard them but I suspect they are great in that regard also) and he will be shipping a set of plans here as well! YIPPEEE!

Shane

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Canada

Thanks for the word on the bearings, JJ.
McMaster Carr is a great place if you live in the US. They used to ship to Canada but now refuse to do so- another example of the 'Free Trade' agreement in action, I suppose.
I haven't found any place comparable in Canada with good prices and selection.
Thanks for the great pictures.
John

Eh? McMaster still ships internationally according to their website, using DHL. Also, just go to a skate/sports shop and get a set of rollerblade bearings if you don't want to fuss with shipping. I've still got several in a bag somewhere...

JJ: so he spring tension is the only thing holding the carrier board in place while routing? No slippage? Stays put?

[QUOTE=Mattia Valente] Eh? McMaster still ships internationally according to their website, using DHL. [/QUOTE]
Last July I tried to place an order (I'd ordered before from McM-Carr)

I got this email:
Dear John,

Thank you for your order. Unfortunately, due to the ever-increasing complexity of U.S. Export regulations, McMaster-Carr can no longer process orders for private individuals outside of the United States . We sincerely regret any inconvenience this causes you.

Please be assured that your credit card has not been charged.

Jaredy Sprogis

McMaster-Carr Supply Company

****
I'll check the skateboard places....
John

Not sure where you are located John, but if there is a Princess Auto near you, check them out .. they have tons of bearings cheap ... good place to get all kinds of junk, small buffing whells an compound, pillow blocks in all sizes bolts springs, rod ... you name it. Almost as much fun as Active Surplus on Queen in Toronto, one of my old faves ...

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

Mattia...The guide blocks on each side and above the carrier also contribute to the stability of the board. They are containtd in 1/2" channels on the sides and are designed to float up and down as the carrier board indexes. I actually clamp them in place when I do the operation.

I believe it serves 2 purposes:

1) The clamp provides a positive stop so I don't run the router off the track
2) It better stabilizes the board.

Bottom line...on 5 boards so far, I had no problem in keeping the carrier board positioned where I wanted it.

John...If you want to order from McMaster Carr, just use XXX Guitars, Inc. as the customer name. That might get around the "private individual" restriction. It's worth a try.

JJ Donohue39058.39375

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JJ
Napa, CA
http://www.DonohueGuitars.com