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[QUOTE=Mike Mahar] Lance, I've made a tool for scoring the top before flush cutting the top. I'll put up a picture as soon as my wife tells me where the camera's USB cable is hidden. It is simple enough to make. Take a block of wood. Put in a 3/4" wide X 3/4" in deep notch in the side of the block.
Superglue an exacto blade so that it overhands the notch.

To use the tool run the block along the side of the guitar with the blade scoring the top. The top overhand slide into the notch.
[/QUOTE]

Mike, I'm going to make one when I get home! I'll shamelessly pinch anyones ideas if they are good!

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Bob, for any real work I use AutoCAD, but for simple stuff I just use PowerPoint, then save the slide as a jpg. That's what I did here.

Pretty hot guitar John Mayes, How'd you do that?

[QUOTE=Dickey] Pretty hot guitar John Mayes, How'd you do that?[/
QUOTE]

How'd I do what? Hide all my screw-ups?

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John Mayes
http://www.mayesluthier.com

You make mistakes John!!!!????

So on bobs image, do you go the opposite direction on the other side of the guitar? since the bit would be spinning the other way on that side??

Just curious...

-Paul-

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-Paul-

Patriot Guitars

[QUOTE=Dickey] Pretty hot guitar John...[/QUOTE]

I enthusiastically second the motion!
That is really pretty.
Nice work.

Steve

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

Whats so pretty about it ! Oh ya! Huh!Huh! Huh!
Everything!

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Support the OLF! Bookmark our STEWMAC link Today!
Lance@LuthiersForum.com

[QUOTE=LanceK] Whats so pretty about it ! Oh ya! Huh!Huh! Huh!

Everything!

[/QUOTE]

BEAVIS! It's my dawg yo!...haha.. I loved that show... (Ok I'm showing my
youth)

I make way too many mistakes! I can usually find a small thing or two
just not perfect on very guitar I make. But I'm getting closer (and further
away) everyday!

_________________
John Mayes
http://www.mayesluthier.com

When routing down hill think of moving the router in the same direction as you would move a chisel if you were chiseling the edge off.

imagine the guitar sitting on one edge, the other, upper edge being the one to be routed. the router should move in a down hill direction, as though it were sliding down the hills thus formed by each bout.
.

by the way john, where did you get your madagascar. i need to get a set for a new client.crazymanmichael38422.6678587963

Well, Here's the photo I promised. It's simple enough to build. Much harder to take a good photo of it.

If I were making it again, I would use a symetrical exacto blade so that I could run the tool in either direction. As it is now, I have to run it "up hill" and take extreemly light cuts. I all I had was the blade that was on it, I would put more of an angle on it so that the blade hits the top with more skew.


I used this on a redwood top and it got no splintering at all. I made the tool because I did get quite a bit of splintering when I bandsawed to top to 1/2" larger than final size. I was lucky in that the splinters all happened to stop by the time they got to where the binding is supposed to be; but it was close.
Mike Mahar38423.4288078704

I wired my router with a reverse switch and I use a bit that can
be reversed also. This way I'm never cutting into the grain.

The reversing switch with reversible bit (left-handed?) sounds like a foolproof way to eliminate tearout.
My setup is a little unconventional using a 3-wing slot cutter of approx. 2" diameter. The pilots are aluminum rings with bearings installed. One ring rides on top of the body while the other against the side to establish width of cut.
I don't have the reversing capability but don't seem to have a problem cutting spruce. Not sure how it would work with redwood.
Nelson

Nelson, could we get a picture of this setup, thank you very much. BD

I thought you'd never ask, Bruce!
The 1/2" shank is hidden behind the upper pilot. The second photo shows one of the aluminum pilot discs with bearing installed. I made up two sets of discs, one to cut the binding rabbet and then the second set for the purflin rabbet. I run these in a full size router mounted in an articulated arm with the body mounted on a turntable.
Nelson

I reduced the file size but looks like I should have reduced the image size also.
Nelson

Thanks Nelson, Okay, now to figure out what may be applicable. No doubt you had this machined? Thank you, Bruce

Nelson: "I run these in a full size router mounted in an articulated arm with the body mounted on a turntable. "

Okay, Nelson, this begs two more pics: The router mounted in an articulated arm and the turntable-mounted body. TIA

I love your work, just fantastic, worth the surf-over. bd
Dickey38423.9850231481

Bruce--I don't have the binding router set up right now but seems like I should have some pix around here somewhere.
I tend to forget that not every builder has a metal lathe and mill to make tooling but, yes, the aluminum rings are bored concentric with the OD.
The turntable setup is comprised of a large lathe that I built several years back for turning wooden bowls up to 32" diameter. This was prior to discovering instrument building. The lathe is primarily for mounting large faceplates on a heavy spindle driven by a DC variable speed/reversing motor. It has a pivot built into the base so that it can tilt onto it's back so that the spindle/faceplate becomes horizontal. This makes a good setup for mounting a 26" diameter sanding disc which works good for sanding the archtop bodies glue joint prior to joining the front and back plates. It also makes a nice turntable for other jobs including machining the binding/purflin rabbets mentioned above.
Another feature of the lathe is a 3" diameter tooling post mounted parallel to the spindle but outside the swing radius. This post accepts the articulated arm assembly mentioned above that holds the router. The combination of this arm with the turntable allows rotating the guitar body (manually) while following the profile with the piloted 3-wing cutter assembly.
Nelson

Thanks Nelson. Sounds like a lot of engineering on a
personal level has given you success. One thing that
I wonder about is the size of the cutter. Does that
help with tearout? The tiny cutters used sometimes for binding may exacerbate the ripping rather than shearing action of the cutter? Speed of rotation is another
question.

Bruce--Yes, I do think the larger cutter diameter gives a better shearing action. You may notice also that the winged cutter has a sharp rake angle on the teeth.
I cut in only one direction, clockwise around the body. One cut for binding and one cut for purflin.
Nelson