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I got the machine hooked up, leveled the table and here are my first actual parts.
They are cut with a 60 degree v-bit so the tight corner areas are not lost. The inlay part is reversed and cut from the bottom leaving a backing that is sanded off after the inlay is glued in.
I'm very pleased with the result so far and hopefully it will only get better as I gain more experience with it.

The overlay is mad rosewood and the inlay is yellowheart

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

Lookin' good John! I guess it pays to buy a machine rather than building it!
I just did an MOP signature logo for one of our OLF friends. If he gives his ok, I'll post a couple pictures of it here.

I'm curious as to why you cut these with a 60 degree bit rather than a straight router bit with a pocket? With sanding, you'll lose some of the ability to control the size of the inlay with the angled bit.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Go forth and post, Dude!

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

In theory you will lose the fine detail in the corners by using a round straight bit. The smallest bit I have is a 1/32" bit and I was not able to get a good tight fit of the tips (especially those under 90 degrees as in the tips of the H.
So by using a v-bit, both pieces retain the points well. Your fitting the sides of the inlay and since they are both cut at 60 degrees, they fit very tightly. Yes it could change sizes if I were to sand too much but you can plan for that and get good results with no gaps.

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

Well John, it sure is impressive the way you maintain the sharpness of the text and edges, that's for sure. I will have to explore this method and see how it works for me with some things. Not sure I would want to try it with pearl though...

Here's those pics:

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Well that sure is tight and nice Don. Good looking inlay for JJ's next!! What bit are you using for that, also feed rate and rpm. I broke my little spiral 1/32" carbide upcut as soon as it touched pearl.

John,
That looks great. That is a very cool technique! I have been struggling with sharp corners like that. My cnc mill only has a 7500 rpm spindle, so anything smaller than a 1/32 bit is just about impossible. I have tried going through my programs and putting in the appropriate radius, but everything gets too roundy looking. With the technique you are using is the depth of cut the same for both pieces? How are you handling your cutter comp? Thanks in advance.

Jeremy

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Jeremy Vonk

That looks great John!
What machine do you have?

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Lance@LuthiersForum.com

John,

The 1/64" dia bit is from precisebits.com, and is optimized for cutting pearl. I believe it is a 4-flute endmill in reality. I plunged at a rate of 2.5 ipm, and cut at around 5 ipm. The passes were .0047". I realize that seems slow, but that's what the specs call for to not break the bits. At over $20 each, you don't want to snap them! I think I could have gone a bit faster, or made deeper cuts, but I wanted to be conservative. I did the pocket with a cheap 1/32" dia 4-flute endmills from Enco. I also did deeper cuts with those, so the pockets went a lot quicker than the pearl. The pocket was .003" larger than the pearl, and was a very snug fit. I created offsets for that in the cad software. Worked out pretty well.

My Wofgang Eng. 350TB mini-spindle runs at 20K rpm, and has extremely low runout.

I also bought a .01" bit from PreciseBits, just to see it. Not sure if I'll ever have the courage to use it!

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Thanks Don, I will re-order some bits and try the pearl again. I think I was going considerably faster than that so I'll start with you feed specs and see what happens.
Lance, I got the "shop bot buddy".

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

Hi Jeremy, the depth of the inlay piece is slightly deeper than the pocket but after cutting, I sand it so that it doesn't bottom out in the pocket. This ensures a nice tight fit on the sides, if that makes sense. I'm using Partworks which is a version of "Vetrics" V-carve, made for Shopbot.

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

Those little bits love breaking, and every little bit matters. Precisebits gives you a good start by providing the speeds and feeds. On top of that you want to minimize runout at your spindle, get the machine motion as smooth as possible, and make sure your shell is set up nice and level so there's not too much variance in depth.

If everything's set up right, then one'll last you a really long time. If anything's just a bit off...snap.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services