[Arch]

I just bought a new cnc router and am trying to learn how to draw arctop guitar tops and backs inside and out. I don't know how to start my arch. Can it be lofted all as one surface or do you have to draw a lot of wire frames. I have BobCadCam Version 20, AutoCad 14, Rhino 3.0. Can anyone help.
Thanks
Randy

[gregmary]

Which Guitar did you want to start with? There are probably other luthiers that have plans that could help. Have you checked www.mimf.com? Good luck with your new toy.

Greg

[Arch]

Thanks Greg. I have 3 different models that I build. I own the Benedetto plans but mine are a little different. I just need to know how to draw the top inside and out. I think I already know but, I was hoping someone who had allready drawn one could give me a few pointers that might speed things up a bit. I can't wait to get this thing in.

[DAB_Design]

Arch, if you have any of it drawn, or pictures of what you are after, I'd be willing to help (it'll be a few days before I can really get to it though -- wierd work schedule).

I'd need to see what you are after though, as I don't know a darn thing about guitars.

[gregmary]

Arch,

I have created models for a mandolin and a les paul guitar. I use "sweep blends". I would have to see your plans to know the best way to proceed. Do you have the surfaced mapped? If you understand the surface in the manner similar to a topographical map it is not to hard to map it into a surface. The mandolin I first created the surface map, then use the thickness map to create the inside shape.

Greg

[Sam Banout]

Hello Arch and everyone else,

I am also trying so hard to draw a Les Paul using Rhinoceros, Catia V5, Solidworks softwares.

Just can't figure out how to do it. What is the most convenient and easy software to draw this kind of object?

gregmary, would it be possible please for you to send me your Les Paul drawing so I can see how it's done? it would be very appreciated. you can email me at [email protected]

Here is how I though it could be done:
1- I started by drawing the guitar profile
2- Then I extrude it to the proper thickness
3- then I draw another profile inside the guitar which will be the path curve to use for the sweep to create a solid part that will be substracted from the guitar body to create the archtop.

the problem I am having is when I sweep a spline over the path, I obtain an empty part without thickness which I can't substract from a solid part.

Any help?

Thank you very much

[gregmary]

Unfortunately I can not help with those software packages. I used Pro-Engineer to create my model and I use what they call sweep-blends. You create a series of cross sections and the computer joins them creating a solid. I then import the model into a program that creates g-code and use horizonal finishing to create a tool path at fixed increments in the z direction. What this gives me is a graphical representation of the top that looks much like a topo map. This lets me visualize the 3D nature of the top and I can tweek the 3D model in Pro-E until I am happy with the shape.

I am working on creating a model of a Benedetto style arch top guitar. I have attached a file that shows the technique I am using.

Cheers,

Greg

[osoloco69]

Hows that archtop model giong? If you get the g-code for the top and back of benedetto's I would love to get a copy of it.

[danaos]

any plans here i realy apresiate
[email protected]

[danaos]

there is some with f holes stile

[sdantonio]

Have you had a look at this thread.

http://www.cnczone.com/forums/showth...t=24800&page=3

[Stepper Monkey]

I don't know about some of the other programs, but ArtCams modeling sysytem is almost exclusively designed for this sort of thing.

If someone already has the 2-D shapes defined in a vector format, and a good idea of what they want for curvatures and cross-section, I have no problem modeling the parts for you guys in very short order and just posting the export files. I just can't cut them, that's up to you router guys.

Just let me know what stuff you need modeled!

While you are at it, does anybody have an SG Bass (EB0 and EB3) template or blueprints?

[rlrhett]

I'm happy to share my method, FWIW. Unfortunately, I don't have a machine available so I haven't been able to test out the design. If anyone wants to cut a couple of plates out for me, I'm happy to e-mail my files

First I actually started in Corel Draw because it has a nice shape blend feature. I draw an outline of the guitar and a pear-shaped area under the bridge. Be sure for this blend feature that both shapes have the same number of control points:

[rlrhett]

Next I apply the blend. I pick a number of contours that makes sense for the subsequent lofting:

[rlrhett]

Then I import into Rhino and clean up some of the control points:

[rlrhett]

Then I "lift" by dragging and dropping each contour line to create the arch. I use a curate cycloid arch to create the arch and recurve. There is a utility that will generate the arch as a curve in autocad. I just import it into the front view, scale it, and lift each top contour to touch the cycloid curve. Can't see the curve in this picture, but I was too lazy to recreate it for you:

[rlrhett]

Finally, I usually close the top contour because that causes problems with the loft and then select all the contours and do a Patch command. Voila:

[rlrhett]

After that, you make it 1/4" thick using offset, cut whatever design you want for the sound holes, flip it over to make a back.

I've gone through the trouble of using the Mad Cam to create tool paths, but without access to an actual CNC, there is no way of knowing if I'm even close.

Good luck.

PS. I should note that after the machine is done cutting you will still need to "tune" the top by hand. Usually that would mean using a small finger plane to carve more int the recurve area. It will depend on the actual wood and the tone you want. One cool thing about making archtops is that you can actually string it up before finishing and carve the recurve until you like the sound.

[Alnico]

Then I "lift" by dragging and dropping each contour line to create the arch.

I did a very similar thing in Rhino by using offset curves (decreasing inward from the outermost) and then lifting each one on the Z axis, and then putting a patch over it. Sorta worked. I'm working on another method that might work better.. I'll share it if it does work.

But I gotta say.... a carved top is probably one of the most difficult guitar-related things to model on a computer for eventual CNC output!

[GuitarEng]

Check out my other post for a quick neck surface tutorial as well as a violin surface that I posted on another forum.

I use Rhino quite a bit...for carved tops I've had more luck using network surface and single and double edged sweeps. I patch stuff when I have to, but try to stay away from it as it is not very controllable. Check out the CSec, Match Curve, Match Surface, and Section commands as well...that should help you out.