I’ve created a neck model for the guitar project I’m working on, and technically it is functional, but I’d like to refine and improve a few things. Please see the items below:
I’ve basically built out a wireframe and used NetworkSrf and PlanarSrf to skin it, but the areas where the neck shaft flows into the headstock has some rippling and angular facets. I would like to understand how to blend the geometry in a little better for a smoother transition:
For this curved transition where the top of the fingerboard drops to the face of the headstock, I created 3 lines and lofted them, then used history to tweak. Is there a better way to create this geometry?
Still concerning the transition mentioned in item #2 above - theres a corner that gets turned where all of this meets the headstock face that is supposed to be more rounded, but because of the way i lofted the lines its a hard angle. I thought of maybe adding some additional lines to have Loft gradually merge that in…or is there another strategy such as using a curved surface to cut that corner a little more rounded?
I am also including some renderings from my CAM software for clarity. Note that on one side of the geometry, the CAM software perceives a small “leak” or tear - not sure why, but it doesn’t seem to affect the simulated carve:
And finally, here is my Rhino7 project file - note that i have additional models in there that i cloned to save checkpoints along the way - this may help clarify how i got to my final model:
Thanks! I had thought about working with it as a solid and doing boolean splits, but it seems a little daunting - had not considered splitting surfaces - are you doing booleans or just something like a trim? @martinsiegrist
@markintheozarks that is closer to what i was trying to do, especially the ‘top’ side where the curvature rolls smoothly over (as pictured) - i may try to refine the ‘bottom’ a bit as it it still a little faceted.
Also, in that picture, the sharp point where the headstock turns - is there a way to round that a little more without breaking the geometry?
I think my issue stems from not being very accomplished at laying out curves to get the surface shapes i want - are there some rules of thumb on how to divide these shapes up, place control points, etc?
perhaps you could share how you set the curves up and surfaced to fix my issues? in your 3DM file i don’t see the curves - did you run NetworkSrf on the surface edges? I don’t see a network of 3-4 curves around each…
Can you clarify what is meant by “networking more surfaces together and tightening them up 0.003”? I think it means making more smaller surfaces rather than fewer large surfaces…not sure about setting up the tolerance. Again, i’m not good yet at setting up lines and control points to get the geometry i want.
I’ll play with this some more this evening - feel like I am over my head a bit, mostly due to lack of time to throw at it.
If i can’t get what i need within a week or two i may. have to look into hiring someone to help me get my models togther
Basically there’s gaps between surfaces by around 0.003" or so, that are leading to the cause of naked surfaces that wont join because they’re outside of the distance relative to the file tolerance.
You could increase the file tolerance to try getting them to closed up, but that will just cause more issues down the road.
No, it doesn’t really mean any of that other than yes it would be better imo to reduce the number of surfaces wherever it can make sense.
I had similar thoughts like that maybe 15 yrs ago, but I definitely got the hang of it within a few months or several.
Once you learn a workflow, and gain knowledge of some Rhino recipes, you’ll gain some good power to accomplish lots of things in Rhino. And there’s lots of ways to do anything.
Technically, depending on what you want to do with your model, it’s possible that it will work out just fine the way it already is.
But it’s always good to know how to jump over or around certain hurdles as they come up.
I could possibly put some time into your file later tonight or later this week or maybe weekend.
It looks like maybe about a 2 hr session would do the trick. But there’s many ways to approach it. The hard part is choosing the directions to go about it.
In the meantime, Kyle shared an awesome link that demonstrates some cool surface recipes, I’m sure I’ve seen it, but I’ll probably watch it again
I will def have those videos queued up for this evening!
I know what my requirements are i just have to develop the skills to make it happen - which is doable on a suffiecient timeline lol
part of it is i need my models flexible enough that i could swap to a different neck shape/profile and easily blend it back in so i can produce a variety of shapes but maintain the heel block and headstock, if that makes sense…hence the initial curves joined by lines and then surfaced to make the main shaft shape…
In general, keep your geometry as simple as possible. Attached are two different versions, one uses plugin XNurbs, which is unfortunately not available for Mac yet. neck_carve_sg.3dm (1.2 MB)
Technically, CAM software should be able to handle small leaks these days. It could just be a matter of certain settings. But the leaks can certainly be closed up if necessary.
I have been doing a lot with Fender style bass neck, have watched Sky’s videos over and over - must watch!
What works for me is I have done my models with CAM in mind first. For the headstock face I created a simple rectangle surface with a curved up end at the fretboard. Then a 2D profile of the headstock shape. That’s all I need to machine the headstock face and the profile. One program to do the headstock face, and another to cut the headstock shape. My 3D model doesn’t even have to look like a guitar neck, but has the geometry needed to machine the neck.
I’ve attached a file of the CAD for the neck back to give you an idea of the surfaces, mostly done with EdgeSrf command and 4 curves. Surfacing is easy, getting the curves requires planning. Sky tells it all!
Yes makes sense that’s more or less how i cut the body - lot of 2D pocket and cutouts with the only 3D stuff being the belly carve…don’t have a full 3D model of the whole thing.
Possible foolish question: you have one continuous surface in your model, presumably made with EdgeSrf from 4 edges - does the command take your profile curves into consideration, or did you actually create multiple surfaces then combine them afterward into one? IOW, I would have expected to see multiple surfaces given the complexity of the geomtetry.
OK - i made it thru Sky’s series, and I’ve taken another shot at the neck based on that and what @Carl_Mesrobian sent me. Please review and advise on how to improve.
The issues that I see are 1) it has some leaks - it doesnt look like the surfaces quite touch some of the guide curves and 2) i can’t really tell but i almost feel like theres a peak where the surface halves meet in the middle, particularly flowing into the headstock. I tried some rudimentary matching but it didn’t seem to help
Any other items that don’t pass the “sniff test”? I opened the model in my CAM software and it looks pretty good.
EDIT; i’ve gone back and cleaned up the curves a bit with the help of the graph tool…a little cleaner but still the leaks…may need some pointers on matching surfaces here…
not sure how that happened, but I guess it has to do with the shape of the edge I was Blending to or dragging the handles too much.
The attached is a lot better, with some point editing neck_carve_sg1.3dm (561.7 KB)
You can use the adjacent surface edges, instead of curves, when building the surface next to an existing surface. The mantra “Sculpt and Match” is constantly in my head as I model these. I have started deleting curves once the surface is done, since one can create the curves from the surface just made. As far as leaks, sometimes simply dragging CV’s will fix it.
I still consider myself a beginner with all this, and find that I discover more in Sky’s videos that I glanced over at first, and what I glanced over is more understandable after more experience with making surfaces.
CurvatureGraph is your best friend.
As far as tangency, etc. MatchSrf or manually moving CV’s. Planning for tangency and curvature with the layout lines is the best (for me , at least), and pays off with the surface that comes out of it.
