OYE! Need help on 3D neck transition

[wbegg]

OK,

I hope someone can help me. I've spent way too much time trying to model the transition for a Strat neck from the neck radius to the headstock contour. I've included a pic of the troubled area. I am using Mastercam 9, which to me is a bit less user intuitive than it should be ( for the price).

Any Ideas? I got the heel contour, not to hard, just a 2 rail sweep.

[bostosh]

Is there definition of the curves you wish to use for this transition?
Arcs, parabola, cubic, Rho curves, etc. these can get exotic.

[Kencor1]

Its been a few years since I did this but if I remember I used 2 separate 2 rail sweeps one for the left side and one for the right side.

[luthier]

You need to draw an arc along the centerline, from the end of the contours on the backside of the peghead, to under the nut area and beyond a bit. One end of this new curve meets the straight centerline from the heel end. At the start of this curve you need an arc perpendicular to it ( cross section of neck at this point) , and at the other end of the curve you need an arc ( another cross section, but it will be a slightly different width because of the fretboard taper. Split the fretboard lines at these places, Use curve-network and pick the 2 arcs, 2 fretboard edge segments, and centerline curve you drew. If it doesn't surface nicely, rebuild the two fretboard line segments so that they have the same number of points in them, and try it again. You'll need an arc the same way down by the heel to make a rounded neck using the same technigue. Over at TDPRI.com ( you are a member there I think right?)....there is a DXF of a tele neck by EHawley. That will help you visualize what you need.

The transition for the peghead contour is harder. Basically I did the same technique ( copy and elevate, )but split the perimeter of the peghead at the points where there is no longer a contour. I connected a straight line at these points vertically at the splits. This gave me 2 straight lines and 2 curved lines for network surfacing on each side of the neck. Same process, rebuild the longer, curved lines so they have the same number of points. Then surface using the network-surface command. I found that by increasing the number of points, I got smoother results.

[Johnny501]

Originally Posted by wbegg OK, I hope someone can help me. I've spent way too much time trying to model the transition for a Strat neck from the neck radius to the headstock contour. I've included a pic of the troubled area. I am using Mastercam 9, which to me is a bit less user intuitive than it should be ( for the price). Any Ideas? I got the heel contour, not to hard, just a 2 rail sweep.

Wbegg,

These transitions aren't trivial. I'm using a dedicated 3D solid CAD modeler, and it still takes a "little doin".
I'm developing a guitar for a buddy of mine, and he's using an off-the-shelf Tele neck. I couldn't find an off-the-shelf CAD model, so I decided to make my own.

Here's some jpegs that illustrate some of the major steps of the process. My intent isn't to show you all the details of all the steps, but to at least show you that it takes a bit of planning and "scaffolding".

I've never used MasterCam, but my hunch is that it might be easier creating the geometry in something like SolidWorks or Pro/E, and then exporting to your CAM program.



















This design can still use a few tweaks, but it's good enough for the assembly model (where I'm focusing more on the body work).

The basic strategy is to lay out a "bunch" of 2D drive-curves that define the major surfaces. (In SolidWorks, you want to use "boundary surfaces"). Then trim these surfaces, and then stitch them all together so that you can make it solid.

It's not rocket science, but again, it's not trivial either.

Good luck.
Hope this helps.

Johnny501
KOZM Guitars