[louieatienza]

I've been doing much of my acoustic guitar work by hand. Unfortunately the realities of carpal tunnel from a couple decades of woodworking, construction, computer work, and playing guitar and keyboards are taking their toll. Been working on my CAD skills, and hopefully I'll be able to automate the more mundane tasks of cutting and roughing, and save the details, tap-tuning and final neck shaping for hand work which I still enjoy...

The sides will have to be bent by hand, but I'll preshape them to match the back radius: (anyone know how to "unfold" these?)
Attachment 313016

The back lining is fairly complex as it curves in three dimensions:
Attachment 313018

The top lining is flat. I do not dome my tops per se, but I will put just a slight radius on the bracing to add a touch of tension, which will effect a very small doming effect by the bridge:
Attachment 313022

The top attached.
Attachment 313024

The neck is attached via bolts to facilitate easier removing and adjustment. Also unlike the traditional way, the neck billet extends as far down the fretboard as possible, which allows for a contiguous support for the fretboard (no more "rising tongue" issues). It should also help with sustain in the higher notes (making a cutaway version as well.)
Attachment 313026

Finally a headstock plate. I'm not a big logo/inlay guy, so this will be a decorative burl or veneer.
Attachment 313028

I have all the raw materials, just a matter of when I'll have the time to cut them all out. Neck blank and neck block will be the most challenging parts to cut.

Next up is to import my bracing designs from my old 2D CAD system and bring them to life in 3D.

[louieatienza]

The neck heel area is a somewhat complicated joint, but allows future adjustment without having to unglue the joint.

[louieatienza]

And the equally complex neck block:

[louieatienza]

A view of the back (with different wood) showing the back curvature and taper:

[louieatienza]

And another pic to show how the transverse brace couples with the L-shaped neck block to keep the neck straight relative to the guitar body:


Not an innovation of mine, rather that of the great Ervin Somogyi.

[louieatienza]

Finished my bridge design in CAD, revised slightly from my hand-made version:
Attachment 313174
Attachment 313176
Hard to tell the curved surfaces...

And finally the cutaway version:
Attachment 313178

These are both multi-scale (fanned fret) guitars. Great for dropped tunings, and more even tensioning from string to string, tighter bass and sweeter trebles.

I also went with a "softer" headstock design.

[fretman_2]

Wow!!

[louieatienza]

Wow!!

Thanks! Though the real Wow!! for me was learning how to design in this particular 3D CAD and drawing the parts all in a span of 14 days! The electric guitar was the first one and a little more difficult to do, but after that the acoustic went a lot easier. I was working mostly with surface based modeling but it was limiting in how it could be edited/manipulated. Very tough to get a watertight model in my current CAD/CAM system.

[louieatienza]

Wow!!

The CAD system I'm using for these parts is SpaceClaim2016. The cost is maybe a little less than some of the other big-name systems, but it is so easy for such a feature-packed CAD. I drew all these parts with zero training; in fact I didn't even read the manual or watch a tutorial (though there are many online to see.) I highly recommend it if it's within one's budget.

[Kosh]

I've been using Fusion 360 for similar, but as yet I haven't tried too hard to model the entire guitar like. I'm happy with modeling parts that I can then CNC to match the bending forms (think block for beveled armrest and scoop cutaway.

My primary use case is inlays and carving the entire guitar neck, which is amazingly hard to find examples of in CAD (for acoustics with a heel, that is). Everyone and his brother has CNC'd a telecaster....

The key for me is lofting (like loft between the heelcap and the neck profile along a curved path. That worked pretty well, Similar for the neck to headstock transition. Will try to put some pictures up for you.

There is also a concept if F360 of "sculpting" which gives a blob of t-splines that you can mold in the CAD space like a piece of clay. I gave this go awhile back and was able to create a fairly decent heel in about 20 minutes, and that was my first go at it. Best yet, you can convert sections for that. So you can loft the curvature on the back of the neck, and the sculpt the end of it into a heel.

[Kosh]

Here are some pictures of my models:

1) Fully lofted neck (with cantilevered fretboard)
2) test using sculpt to make the heel
3) new guitar bridge!
4) One of my nuts - my wife has the other one. (couldn't resist).

Attachment 313956

Attachment 313958

Attachment 313960

Attachment 313962

[InMesh]

Kosh good humor and nice work might I say I have on and off looked at what Taylor have done in so far as fitting the neck to body and I believe they are machining the edge of the heel with a ball nose cutter and their cavity on the body with the same ,so when it is bolted up and shimmed it fits really snug .Food for thought I guess.

[louieatienza]

Kosh good humor and nice work might I say I have on and off looked at what Taylor have done in so far as fitting the neck to body and I believe they are machining the edge of the heel with a ball nose cutter and their cavity on the body with the same ,so when it is bolted up and shimmed it fits really snug .Food for thought I guess.

Actually they are using 5 axis foe the neck pocket. But even they do not have ultimate control, otherwise they wouldn't need shims.

Kosh those models look pretty good... I've done a few ways, but I find the easiest is making a wire frame then skinning it and stitching up the surfaces to solid...

[Kosh]

Actually they are using 5 axis foe the neck pocket. But even they do not have ultimate control, otherwise they wouldn't need shims.

Kosh those models look pretty good... I've done a few ways, but I find the easiest is making a wire frame then skinning it and stitching up the surfaces to solid...

Well, to be fair the shims are so they can be adjusted later as the guitar ages.

I opted for the adjustable set screws on that front .

[louieatienza]

Well, to be fair the shims are so they can be adjusted later as the guitar ages.

I opted for the adjustable set screws on that front .

That's what Taylor says... But they use shims when the guitar is brand new. Not a knock in that sense (I actually own a Taylor 100 series and have owned a T5) though they actually have a machine that analyzes the neck pocket geometry to the bridge using lasers, and can determine the proper shim. So why not get the neck pocket right in the first place using the technology, and leave the shim for the future adjustment? I do have other issues with them, like taking control of the ebony market (ever wonder why Martin and Gibson are moving to phenolics?) and using plywood sides, even on their high-end guitars? Also they don't glue their bridges fully, which leaves an easy surface to buff, but I've read many problems of bridge lifting. By design, but still, it irks me.

[louieatienza]

Here's a view of the neck (seen in my CAM system.) I 've been moving into a more modern, flatter heel, that blends with the cutaway. I used to use a 2" carpenter's chisel, a couple rasps, and sandpaper with different blocks, to shape a neck. I still will do that, but I use the CNC to hog as much off as possible so that I can concentrate on the details.

[louieatienza]

Here on an actual guitar... More rounded heel on this.

Attachment 313966

[InMesh]

I would agree that Taylor have bought up most instrument wood supplies to lock others out ,here in Australia we have some nice choices and he knows we have figured black wood same species as Koa .

[warrenb]

Actually they are using 5 axis foe the neck pocket. But even they do not have ultimate control, otherwise they wouldn't need shims.

Kosh those models look pretty good... I've done a few ways, but I find the easiest is making a wire frame then skinning it and stitching up the surfaces to solid...

Taylor Guitars uses no 5 axis machinery. All 3 axis with jigs and fixtures.

[louieatienza]

Taylor Guitars uses no 5 axis machinery. All 3 axis with jigs and fixtures.

I'm pretty sure they do. I believe I even read an article in Wood & Steel where Bob Taylor actually discusses this.