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Can a touch probe be used to reverse engineer/program an existing neck?

Theoretically if the tip is long enough to clear the heel, yes you could scan a neck. That said, I don't think that's the best way to import a neck. To scan a neck in that way, you need both software that can perform the scan (there are some macros for Mach 3 that will work) and different software to manipulate the point cloud generated during the scan. If I recall, Rhino can import a point cloud and use that to create surfaces.

My order of preference would be:

1) Build from scratch using 3D modeling software (what I did)

2) Laser scan - this is something you can sub out. Send the neck to a scanner and they'll get it done for you much more easily than you could do on your own.

3) Touch probe scan.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Hi Andy,

What would a laser scanner service be called, so that I could try to find one?

Don't forget profiles. It's pretty easy to take profiles with a profile gauge...or Bondo, wax paper, a saw, and a flat-bed scanner. I liked the second method, you can scan the profiles and use the image from the scanner in Rhino as a background image to make the files. Put a ruler on the scanner to make sure you scale the image right. You can get the headstock geometry directly by holding it on the scanner.

As Andy says: the probe still works, but there are hassles unless you've got a really nice probe and spend a lot of time on setup. It's far from turn-key. Rhino does work very well with scan data of various types, both point clouds and meshes. I've used point clouds in Rhino to reverse engineer necks, bridges, people's legs...

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

I sense a lot of reading coming up...

If you're getting into CNC that is a true statement regardless of if you get a touch probe or not!

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I believe it. The plan is to have someone else do the intelligent design part and me just be able to put wood in machines and pull parts out.

I'm sure it's gonna be that simple:)

Yea, that's the rub isn't it?

If you have a very small number of parts you'll be making, that might work but...it also may be more expensive, especially depending on how you value your time.

In full disclosure - I do sell CNC'd necks, bridges, fretboards inlay etc.. That said, some of my best customers have their own CNC machines.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I know, wish I could make it that easy on myself, but, the profit you need to make is the money I need to save.

Not to say your prices are unreasonable cause I don't think they are, but...

20.5 necks would be the same price as a machine, which is only 4 months output for us. Plus, I need autonomy over my time...

Would that I could.

meddlingfool, have a look at this

http://www.david-3d.com/en/

Back in college i successfully built a laserscanner using this software. Scanned in one of my Les Paul necks as a buddy wanted to copy the feel...it worked perfectly.

Theres also ways to use an Xbox Kinect, but, I'm not a fan of the detail. For quick scans of bodies it isnt bad.

Well, that is pretty cool!

I used to use a scanning service in Dallas. Trying to find the name? The part needed to be either sprayed with a light gray paint or they put some type of power on it. The cost was around $150 depending on the complexity of the part. Always had great service and outstanding results from the files made. These were for clamshell molds for pouring aluminum parts.So it can be cost effective if you find the right servicing agent. I have tried the Davids scanner and it is at best very hokey. I would trust a good probe and point cloud instead.
MK

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I'm outside looking in, just farther from the window than most.

I find a neck to be something that will need to be customized to some extent after coming off the CNC. So keep that in mind. You can do some of it in your toolpathing but other things like headstock shape should be oversized in a lot of cases. I like to get the tenon exact though which helps a lot. It is a process and taking control of it yourself is a good idea. If you are really organized, you CAN just push the button and have the neck done, but then it is only good for that one model. Creating one for each is really time consuming. I have two necks, one with a long tenon and one with a shorter. Both have 5 degree angle at the neck join but not all my guitars require that. So I do need to change that in some cases. but I have a jig for a pin router that makes quick work of that. And I do like to use a file and chisels at times. My peghead face veneer is exact and after gluing to a paddle or oversized headstock, I can trim the mahogany to it. It works fine. Plus the holes for tuners are in exact placement. Again a method is helpful.

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Ken