Woah, thanks for the replys guys, this was fast. I thank you all for helping and offering your advice with this.
Michael, I now understand what you mean about the fillets. I just assumed it would work similar to loops in polygon models (how wrong was I?) I think your first method is what I am looking for. Do you think it's possible for me to "fake" the second lines fillet by using a loft? or would it be possible for me to fillet in certains areas where the surface doesn't go flat?
The second method also looks interesting, and I think I will put it to use on other objects needed for the full guitar. Thanks again.
Burrman, I actually like the result. The outer edges are nice and smooth, it's just the inner sections by the neck that bother me. Would you mind showing how you did it? I can't seem to get anything out of blend.
John,
Yeah, your actually right in that with the blend method and a default value of "1" for a G1 the part where the body meets the top of the neck gets all pinched up, so the result you see here or in my previous post is not what you would acheive, I got a smooth transition with a ".5" G1 but its a drammatically different level of smoothness for the edges.
Possibly redrawing the top curve to be much smaller can produce a different result with blend but I have to say I took Michaels model through to a solid and it actually looks like a guitar! I'll poke around a bit more and If I get anything substantial with blend I'll post back. Have fun!
> Michael, I now understand what you mean about the
> fillets. I just assumed it would work similar to loops in
> polygon models (how wrong was I?)
:) Yup, it is pretty different. Fillets actually do quite a large number of calculations, including making offset surfaces (surfaces that are a constant distance away from the existing ones), and calculating the curves of intersection between 2 surfaces. Then comes some other stuff like creating fillet surfaces that follow those intersection curves, and then doing some additional extensions and intersections between the fillet surfaces and finally filling in corner pieces where different fillet pieces might meet.
Since there are a lot more complex calculations involved, there are also a lot more things that can go wrong than just pushing points around in edge loops... But the upshot is that the final result is a very accurate piece that has a cross-section of an exact circle.
You tend to get the best results if you have pretty "clean" geometry.
> I think your first method is what I am looking for. Do you think
> it's possible for me to "fake" the second lines fillet by using a
> loft?
It would probably be difficult to get good results by doing that. You could put in a "fake" piece with a loft definitely, but it will probably look pretty fake as well because is difficult to produce a smooth result with that method. The loft that you generate will not be ensured to be smooth with the adjacent surfaces. That's another big difference between working with NURBS and working with sub-d polygons - with your NURBS constructions just building 2 different surfaces adjacent to one another with any particular tool does not guarantee that they are smooth to one another. But there are a couple of particular tools like Fillet and Blend that you can use that are set up to build a result that is smooth to adjacent pieces.
The other way that you generally ensure smoothness is to build your model in larger sheets instead of in small pieces or strips when possible. You can pretty easily guarantee smoothness of a single surface construction, like one loft will be smooth inside its own generated result as long as your input curves are also smooth.
So it can help if you build what should be a smooth section as a larger surface sheet instead of trying to do it in diced up bits.
When I saw your result that had 2 surfaces that were both flat, it made me think of building one single larger surface sheet (with that loft method) there instead of that.
But just a note - it is also possible to go too far in the other direction and try to build too much out of a single surface as well. Each "larger sheet" should be a kind of logical component of the model, it can also cause problems trying to build a model made up of many different shapes out of only one single surface as well..
> or would it be possible for me to fillet in certains areas where
> the surface doesn't go flat?
That's probably possible but you would likely need to dice up the model into different pieces to make that happen.
>>Burr, so that's what you sound like :) cool tute dude. Camtasia??
I found that a person never sounds like what I had imagined! I wonder what I used to sound like to you??? He he!
(Since I used other space I could add the audio without worry of size. For me it helps with the understanding of whats happening on screen and the thought process of the creator!)
Yes that was Camtasia. I have another one called captivate which is a pretty powerful tool but not as down and dirty as camtasia. It needs more massaging after the fact. So for a quick record and post its camtasia. Actually If I didnt already have the camtasia loaded I would just use Jing.
Hi Matthew, that one looks great! A lot of details in there, even the little twisted parts at the very ends of the strings wrapped around the pegs, cool!
Hey, I thought after doing the "test" guitar I could move on, and whilst I did get a better understanding in Moi from you guys, I am about to attempt this and struggling to see how I can create it. I've tried several methods in this thread, but I'm getting bad results. Mostly these "arch" shapes, along with the filleting of it.
I've included my shapes, along with a reference. It's seriously driving me crazy, as I personally have this guitar and want to recreate it in 3d.
Hi John, MoI's filleter is not really going to be able to handle those spots where you've got surfaces that are partially tangent to one another but then further along come to a crease.
For MoI's filleter to work those surfaces are going to need to meet at more of an angle to one another throughout their entire common edge.
Here is one of those spots that I'm talking about:
In this version, I have adjusted the top shape inward slightly to avoid that situation and make a more continuous crease along the shared edges between the surfaces:
This version can now be filleted throughout (using v2 beta Sep-21 version):
Result 3dm model is attached as 002_filleted_3dm.zip .
If you don't want to shrink the upper profile down at all, then that shape is just not going to be possible to fillet in MoI (at least not for some time to come anyway). You could try some other NURBS programs that have more advanced filleting than MoI such as SolidWorks, or you could also try switching to a more "low level" surfacing approach where you work on constructing surfaces more individually rather than using the solid modeling tools. That would be like building in some of the fillet surfaces by doing things like sweeping them, rather than using the solid modeling tools. But that tends to take a lot more time.
Once again Michael, I am amazed. With a few tweaks on the fillet sizes it would be exactly what I was trying to achieve.
What I don't understand though is how come it's possible to fillet the whole thing at once, but not by doing the different edges around the body? I need two different fillet widths, it doesnt seem like it's possible =\
Part of the problem with seperating your fillet's is say you do the top one first
Then how do you consider this next?
Here is an example I made by lofting just the bottom and top curves, then I could fillet the top and bottom seperate. It produced a kind of variable, but again changed your original shape a bit.
> What I don't understand though is how come it's possible
> to fillet the whole thing at once, but not by doing the different
> edges around the body?
When you try to fillet in different passes, the initial fillet ends up creating some sharp corners, which creates difficult topology for the next fillet after that to try and deal with.
Burr has a good example and illustration of this above.
It tends to be ok to do multiple fillet passes if you have all smooth edges but sharp edges can create more difficult situations.
> I need two different fillet widths, it doesnt seem like it's possible =\
No, not currently in MoI, at least not easily. I do have it on my "todo" list to enable setting different batches of fillet radii within one single go of the Fillet command though.
That would probably be what you would need to solve this case.
guitar.jpg
