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I'm having trouble filleting the edges of my solid body model. The problem is the tip of the horn which is on the sharp side. I assume it's because the tip has a smaller radius than the fillet. The fillet extends off into space.

Have you tried editing the handles at the horn before applying the fillet? Filleting isn't one of Rhino's strength tbh, do you machine the fillet from the model or is it for rendering/visualization purposes?

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www.morganguitarworks.com
www.morgancustomguitars.com

I'm trying to blend an arm contour into the edge fillet and rim smoothly so that I can machine the arm contour. I'm not having much luck getting the arm contour surface to play nice with the body either.

Maybe the solution is to draw the edges of the fillet, a cross section and sweep two rails around the body?

If you can post a photo, Sheldon, then I can probably point you in the right direction to finish up your blend. I'd need to see it to figure out what's 'missing'.

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Rather than do a fillet on something like an arm contour I treat the body as a solid and draw a curve to use as a wirecut - cutting the contour and the fillet in one go. Of course this only works if it's a flat Fender style contour.

Extrude you body outline both sides of the curve so the model is twice the thickness you want (makes the cut easier) Draw your curves, I start with the one that defines the limit of the contour, then draw another curve perpendicular from the original. Rotate the second curve using 3d rotate to the angle you require. The draw a third curve from the end of and in line with the now angled curve. Align the Cplane with these curves and fillet them to whatever radius you require and make sure they're joined. Without changing the CPlane use a wirecut to trim the body to the correct thickness and get a filleted forearm contour in one go.




(Obviously I'd already applied the fillet in the screenshot above)


You can add fillet handles to define a change in fillet radius and by adjusting the space between them the rate of change.

Start by choosing filletedge then add extra handles, then edit those handles with your desired radii. The two inner handles in the shot below are at a smaller radius than the outer ones and spaced to give a suitable transition - in this example because using a large all around radius would undercut where the neck plate would sit - I know this is the top edge, it was done quickly to demonstrate the technique

http://www.morganguitarworks.com/sheldo ... handle.jpg

And how it looks afterwards, as you can see from the first shot there is no problem with the fillet at the forearm contour break.

http://www.morganguitarworks.com/sheldon/fillet.jpg

I'm sure there are lots of other ways to do it but this always works for me.

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www.morganguitarworks.com
www.morgancustomguitars.com

Sorry to make my first post so needy , but would you mind expounding on this post? Your fillet especially at the transition where the arm contour starts is something I've been fighting with.

Thanks!
-Mike

Here's a photo of the arm contour I'm trying to blend with the fillets. I seem to hit a brick wall with everything I try.

Hi Sheldon,


email me the model on neil (at) morganguitarworks.com and I'll take a look - I have some ideas.

Cheers,

Neil

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www.morganguitarworks.com
www.morgancustomguitars.com

Neil mentioned wire cutting in another thread. That was the ticket to enable filleting the arm contour with the top edge. There's still the problem of the fillet looping on the horn tip but that's minor.

Good to see you solved it before I even had a chance to look at the model

I rarely bother modelling the fillets for the body round over as I do them at the router table these days.

_________________
www.morganguitarworks.com
www.morgancustomguitars.com

Sometimes when I fillet an edge, the edge doesn't trim, sometimes it does. I don't see an option for trimming. What am I missing?