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I like to use a curved end graft on my guitars, feeling that it's curves compliment the curves on the rest of the instrument.

I cut the first one by hand and it took the best part of a day to get it just right. I've come up with a jig that makes the whole process take less than 15 minutes. In fact a lot less time than it takes to write this tutorial.



It's a pretty simple jig. I had to add a second bit of timber to the piece of plywood in order to get enough depth, so that the flush cutting bit I use, has something to ride against. The dimensions of yours may vary.

You will also notice that I've marked the center line on the jig. It's just a matter of lining it up with the center of your back and top, then snug up the wing nuts on the threaded rods. Double check that everything is right, and then your ready to route the end graft cavity.



I set the depth of cut to just remove the thickness of the sides. You'll notice that I chalk in the direction that I need to route the top and back for the bindings. Anything that helps minimize mistakes in the rush of getting everything just so. The older I get the more I find I need little things as reminders.



I then use the end graft jig to mark out the piece that I'm going to inlay. I had to play with the design a bit to get this to work without a lot of painstaking fitting.

Although the piece is curved, it is actually also a wedge. There is a bit of leeway where the piece will fit. This makes it very easy to get a good tight fit with minimal work.

I have purfling running along the bottom of my bindings and around the end graft. Here I'm holding the purfing tight against the edge of the jig and running a sharp pencil along it. Cut close to the line and finish up by your prefered method. I use a drum sander in my drill press.



Trial fitting. It was a prefect fit first time up.



All glued in and ready to clamp.



Just light clam pressure. I've tapped the "wedge" in so it doesn't need any clamping in that direction.



Scraped flush and trimmed to the top and back, ready for routing of the bindings.



The finished end graft.

To complete the end graft/binding design I set my binding cutter depth of cut to JUST the depth of the binding (not including purfling) and do a pass over the end of the graft  plus a little on each side. This is important to do fist, as it it easy to get carried away if cutting the full depth and route the end graft off too deep...don't ask how I know.

Then I reset the depth of cut to include the dept of the purflings, and cut the the binding ledges in the  rest of the body, being very careful as I get near the end graft.

I bring the cutter JUST up to the purfling on the side of the end graft.

The miter is then cut with a very sharp chisel, using the polished back of the chisel as a mirror and watching the reflection on the back to tell me when the angle is right. Then make the cut.

For this to work the chisel needs to be really sharp or you'll just mash the purfling.

Hope this is helpful.

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Allen R. McFarlen
Barron River Guitars & Ukuleles
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Cairns, Australia

Allen,

Great tutorial! Very nice pictures. Thanks so much, I will use your technique and fixtures on my next build.

Best regards,
Max Bishop
Brighton, Michigan

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Max Bishop
Brighton, Michigan

Thanks Allen, nice and simple way to do a very nice curved end graft.

Cheers

Kim

Great tutorial, Allen. Thanks for posting.

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now known around here as Pat Foster
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http://www.patfosterguitars.com

That's really great, Allen.  Is the curve, an arc of a circle?  I know the curve would have to be consistent so it would act as a wedge too.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

It's an arc. I used a flexible steel ruler and bent it to get the arc that I thought would work. It took a few tries to get everything to work out, but this design has given my a fair bit of "wiggle factor".

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Allen R. McFarlen
Barron River Guitars & Ukuleles
Facebook
Cairns, Australia

Terrific job...I've wondered how that was done. Thanks for the time it took to put this together. Greatly appreciated!

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Eagles may soar, but weasels don't get sucked into jet engines.

Why not use the jig to also cut the end wedge peice as well? Just seems like it would be much more accurate, not any more work to set up, and should eliminate sanding errors. You'd need to stop at woodcraft and pick up this....

Allen,

I love the curved wedges too! That's why I looked for a good way to make em too. I tried to post the link but here goes again, for the Woocraft inlay kit

Great tutorial Allen.

If you wanted to use that woodcraft inlay kit for cutting the wedge you would have to somehow take into consideration the depth of the purfling lines flanking the wedge. Those lines might vary from one guitar to the next depending on the decoration scheme. How could you make the inlay jig adjustable to allow for that variable?

Thanks Allen- Great job on the tutorial.

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Anderson Guitars
Clearwater,Fl. 33755

[QUOTE=Terry Stowell]Why not use the jig to also cut the end wedge peice as well? Just seems like it would be much more accurate, not any more work to set up, and should eliminate sanding errors. You'd need to stop at woodcraft and pick up this....


[/QUOTE]

I had thought of how this might be done, but don't have the kit that you have. In fact ,although Cairns is a small city, we are basically at the ends of the earth when it comes to getting anything a little out of the ordinary. You should have see the blank stares I got when I asked around town if I could get some 24" sanding disks for my radius dish. Most everything I have to get mail ordered and shipping gets to be a bit much.

Your right though, it would make the job more accurate, but I would have to be using the same binding on each guitar, or have to use a different collar, or shim it with tape etc. Back to trial and error and more fitting. 

But as I said, the whole process has only taken 15 minutes from start to finish once the jig was made. I've used it on 2 guitars. The one I just posted and the current one I'm building.

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Allen R. McFarlen
Barron River Guitars & Ukuleles
Facebook
Cairns, Australia

Last night I could see all the pictures Allen posted. (Thanks Allen. Cool system.) This morning they are gone. Terry's are there, so I know the system is working, per se. Lance, Brock, did something break behind the curtain last night?

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Aoibeann

I think Allens server is down or it has reached its max transfer limit.

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Lance@LuthiersForum.com

UGH, I was looking forward to seeing that one.
-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

Yeah, I use a similar ststem/jig, to account for the purfling it is a trial and error process but really pretty simple, I just used a few rounds of blue tape on the bearing guide to gain a bit of space( 1 round per cut until the proper width is found). Here is what I ended up with, a nice tight fit. Depending on how you design the jig you can alter the shape of the tail piece as well...adjust the width of the fluting from top to bottom by sliding the jig up or down on the guitar body(and inlay).




Greg

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Gwaltney Guitars

Since his pictures arn't showing I've included a few of my jig, notice the 2 padded/radiused cauls that are adjustable, moving the entire jig top to bottom which allows the change in fluting I mentioned earlier. These pads/cauls are also adjustable by way of 4 independent bolts(2 per side)this is important for the purpose of aligning the jig properly on the guitar body, without them the jig just wants to sit wherever it darn well pleases.




Cheers,
Greg

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Gwaltney Guitars

Here's a pic of mine.
I have both male and female jigs to route the cavity and shape the inlay on a table router.

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Hank Mauel

Sorry everyone. I updated my web site last night and toasted all the photo's of this and my cypress guitar.


Thanks for the personal message. Thankfully I had a back up.

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Allen R. McFarlen
Barron River Guitars & Ukuleles
Facebook
Cairns, Australia

Thanks everyone who posted these. Allen, what species are the sides in that first guitar?
-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

[QUOTE=j.Brown]Thanks everyone who posted these. Allen, what species are the sides in that first guitar?

-j.[/QUOTE]

The sides and back are EI Rosewood. The top is some Figured Cypress, and the bindings are Silky Oak.

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Allen R. McFarlen
Barron River Guitars & Ukuleles
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Cairns, Australia