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Hey All,

I am trying to put the finishing touches on a PRS McCarty model, and be it that I do not have the actual guitar, I tried to model one from pictures, and scattered info on the net....(Did some very quick low-quality renders)

Anywayz, here is what I got so far in Solidworks (Will start work on the neck next). I am also planing on making the tenon for the neck extend into the second 'bucker, under the maple top...Will probably cut the top out of some cheap pine first, to make sure it comes out OK...

What do you think?

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-CyborgCNC
http://www.cncguitar.com
https://www.facebook.com/CncGuitar

Beautiful model and render. But why extend the tenon that far into the body? Asking out of ignorance so be kind!

Mike

Well, I was doing some searches, and i found a few folks who made the tenon longer, in hopes of improving the contact with the body, hence more resonance, and probably stronger as well. A lot of it I am sure is "black magic" but at the same time, it does make sense. So I figured, why not?

Here is one more, after I found an image of some bookmatched maple, and rendered again with it...no textures ir anything, just quick renders in Solidworks...

_________________
-CyborgCNC
http://www.cncguitar.com
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They look great! I only wish I could do that. LOL!
Mike

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

The PRS neck joint is very strong. We used to smash the prototypes when we were done proving out G-code (these were built from mahogany, poplar, or whatever else we had laying around). The necks will break in front the heel, but I don't think we ever saw a neck actually break out of the neck pocket.

Trev

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http://www.PeakeGuitars.com

Trev are you talking about the neck pocket extending through the bridge pickup or did PRS do it that way?

Mike

Their current neck pocket extends into the neck pickup cavity (it ends before the back end of the pickup cavity). I think this is how he has it modeled right now(?).

Trev

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Yes, that is correct: In looking at many PRS model pictures, it ends right before the back of the neck pickup. HOWEVER, I decided to extend my tenon, under the maple top, and end it before the BRIDGE pickup...Kinda going for that "hybrid" and "almost" neck-trough model, but not quite.

(It is quite easy to change this however, by simply going back into my design tree in Solidworks, and changing a a couple of dimensions....)

_________________
-CyborgCNC
http://www.cncguitar.com
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cy, you have here the perfect situation to do a comparison test. Make two guitars with as identical wood as possible, but use the different neck pockets and see if there is any noticable tonal differences or difference in sustain.

Mike

Actually, if you are designing the neck joint the same way PRS does theirs, then you'd be hard pressed to make it extend all the way to the bridge pickup. It's not just a straight tenon - the fingerboard taper extends all the way to the end of the heel. The neck is hand fit to match up the neck pocket and is pressed in place from above. You'd have to either cut thru the chunk of maple between the pickups - or - you'd have to have that chunk hollowed out so that you can slide the neck back and then press it into place. The neck angle is also setup at the same time the side to side fit is done - right before glue up. It's a great neck joint - much better in my opinion than the tenon joints you see on *some* electrics (what are those other ones called...Gibbons? Glibbies? ).

Trev

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Well, this build is actually the one that inspired me...

http://www.guitaristjeffmiller.com/guitars10.htm

Basically, cutting a long tenon, BEFORE the top goes on, then gluing the whole thing together, once properly fitted. I am going to shoot for some very close tolerances, as the CNC machine should make light work of that...I am also thinking, I will cut the angle into the body pocket, that way, the tenon of the neck will be kept nice and simple, and straight. I can angle the neck, or I can angle the pocket, either should yield the 3 degrees I am after...

Again, Using solidworks to mock all this up, before I do any cutting, sure does help!

But your description makes perfect sense Trev...

_________________
-CyborgCNC
http://www.cncguitar.com
https://www.facebook.com/CncGuitar

cool, good luck!

Trev

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http://www.PeakeGuitars.com

BTW....the miller PRS#2 red is on ebay right now....$2800.

Mike

dang I LOVE Solidworks!!!



She is done....just some finishing touches...now for the cutting and machine paths!

_________________
-CyborgCNC
http://www.cncguitar.com
https://www.facebook.com/CncGuitar

what CAM software are you using?

nevermind. i just went to your site -mcam x2

very nice work!

OK..So I HAD to fret her up, polish the frets, and then Polish the fretboard!!

LOL!!!

_________________
-CyborgCNC
http://www.cncguitar.com
https://www.facebook.com/CncGuitar

Is there a Solid Works demo version? I would love to try it...

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

You know, I thought there was, but I googled it and it didn't come up.

You can get what is basically a free version of AutoCAD from the makers of SolidWorks...! http://www.3ds.com/products/draftsight/

This is a great tool to get started in CAD. SolidWorks is a significant investment ~ typically around $5,000 just to get started. It's nice stuff, but not necessary in my opinion unless you are really doing a lot of CAD work.

Trev

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http://www.PeakeGuitars.com

All you need is a student ID!

If you know someone, you can get an educational FULL BLOWN version of Solidworks for around 100 bucks....it is a 1 year license....which you can re-use the following year...

You must however have a valid student ID.

Trust me, it is worth the investment. I have tried many packages, nothing beats Solidworks (In my humble opinion....).


http://www.solidworks.com/sw/education/ ... d-mcad.htm

_________________
-CyborgCNC
http://www.cncguitar.com
https://www.facebook.com/CncGuitar

Well, did about an hour of cutting the other day...

Then I did a little sanding...dang I LOVE Mastercam!

As you can see, i also cut the inlay, and did a dry fit..No need for any filler! (FB needs to be sanded still, as you can see the tool marks from doing the radius...)

And to think that people actually did this by hand???? LOL!!

_________________
-CyborgCNC
http://www.cncguitar.com
https://www.facebook.com/CncGuitar

Cy did you use a flat bottom end mill for cutting the fret board?

Nice inlay fit there too!

Mike

Yes..I used a flat bottom mill to radius and cut the fret-board out...

I used a .023 fret mill for the frets (fret bottoms are actually cut at the same radius as the FB, which is 10 Deg.).

Thanks!

_________________
-CyborgCNC
http://www.cncguitar.com
https://www.facebook.com/CncGuitar

Most people use a ball mill to radius..and I def'ly noticed the tool marks on your fingerboard. I was wondering how you had it jigged up? Do you have a 4th axis? I've always thought that would be a nice way to radius a fingerboard.

Trev

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http://www.PeakeGuitars.com

Hi,

Yes, a ball mill will yield a better finish, but sometimes I get lazy, and I do not change tools!

Either way, it comes down to how much sanding you are willing to do after the cuts. I usually cut as you have seen, and then, using a radius sanding block, I bring the fretboard to where it should be. Besides, I do the inlays, and they will need to be sanded flush anyway, so this is not a big deal for me.

With a ball nose bit, and a finish/surfacing pass, with small step-over, you could basically bring the fretboard to a very smooth finish, with only finishing/polishing steps required after that. Off course, your machining time will go up, etc.

I do not have a 4th axis, nor do you need one...I usually do a flowline tool path in Mastercam, on my fretboard model, which has been modeled according to the radius I want. It is also quite easy to model a compound radius, with a very smooth transition from the top to the bottom. It is a 3D toolpath offcouse, since it does involve a surface.

For the frets, I do the same, but I use a 3D contour, so that it follow the radius at the top...hence the bottom of the fret slot, is an accurate representation of the surface....It all works out in the end...

_________________
-CyborgCNC
http://www.cncguitar.com
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LOL, I must be strange...I'd rather change a tool than sand more...!

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