Suggestions on modeling technique

[Anonymous]

Hey, you experts out there. I have a pretty complex geometry that I want to model and 3D print. I am pretty new at Fusion 360, and I know, you should start easy and level up, but... I'm a little stuck at the following part of the model (marked red):

Red marked is the problematic area

With the bottom part being a surface body and the main grip being a T-spline body I don't know how to get a smoother transition from one to the other. I have tried modelling everything as a T-spline body, but that did not work for especially the tight radius on the backside of the stick.

I would be thankful for every pointer in the right direction, even telling me to start from scratch! But I simply don't find any resources which can help me with that, at least for my skill level, pretty complex geometry.

Attached you find my current state to get a better view of my problem.

Thanks for at least reading this 😄

[davebYYPCU]

Not start again, but build the small lower part onto the t-spline.

Move the t-spline forward in the timeline as far as you can, use the lower edge of the t-spline instead of the sketch profile.  Currently your rails don't connect to that edge.  Edit the rail sketch and then when making the surface loft you can call tangent to the t-spline edge.

Might help......

[Anonymous]

Wow, why did I not come up with that! That tangent loft from the T-spline body is exactly what I needed. That made me even get rid of the rails which I only needed because otherwise, the loft would create a crease at the inner radius.

I'm learning so much from seeing how other people accomplish things, thanks so much!

Now another question, if I may ask: How would you go about thickening/shelling the body? As far as I tried it the only possible solution was the (sadly nonparametric) thicken function within the freeform environment. Neither shelling from a solid body nor thickening from a surface could support me there. These at most worked for like a thickness of 1mm, but not the 4-5mm I want to achieve. The absolute optimum would be a parametric shell for all of the existing body geometry.

The problem seems to be at the thumb-button recesses, but would there be a better modelling approach that I'm overlooking?

Attached again is my model if someone wants to give the thickening a try. I know, my timeline has defects after the point where I created the two surfaces for the grip, but I will fix that at a later point.

The grip I'm trying to somewhat match is the following one, but I want to iterate the shape with 3D printing, to have an ergonomic geometry for me, that's why measurements/accuracy is somewhere back in my design priority.

[davebYYPCU]

First impression was that without the rails, the inside of the Bend was odd, so I fixed the rails.

My guess is you will be stuck with Tspline Thicken.  What I would try,

Modelling window, (no time today - can’t tell if it will work)

copy the (Tsline’s) solid body, don’t move it, hide original, 

scale it down (non uniform,) so height does not change, 

Combine cut it out of the original. (Manual shell)

Failing that, @TrippyLighting might sort out the Tspline star edges, so it can shell.

Might help...

[Anonymous]

First of all: Take all the time you need, every second you spend helping me fix the problem is worth so much. Especially in the time we live in it's sadly not natural to help others anymore.

My problem after working at it for a bit is the following: Every way of creating a surface loft for that bottom part fails with thickening more than 1 mm. With a loft within the form environment, I can form-thicken it. This then results in two bodies that don't want to combine (first yellow failure in the timeline). The result looks visually pleasing, but I think the problem is that these bodies don't match 100% as seen in the below closeup view.

The cause of that little gap? between the surfaces is in my opinion the mismatch of the t-spline control points especially seen in the box-view.  But I don't know if I can manage to match this up without destroying the free-forms. I think I might give it a try...

Having spent less than a week in Fusion 360 I'm now a bit stuck and frustrated, but I don't want to give up. There needs to be a solution, I can't be the first one to model an object like that 😂

[TrippyLighting]

Have you taken a look at your T-Spline in box-view mode?

It's no surprise that this does not shell.

 

[Anonymous]

Yes, I have somewhat taken a look in box-view, that's what I initially used to delete the faces in the thumb-button recess areas and to add quad-faces. That was at least the one thing that made me proud thinking I only used quad-faces, no triangles, or >=5-sided N-Gon faces. (Why do I write thinking: Just took a look at the repair body tool finding way too many star-point errors. Haven't taken a further inspection, that needs to be done)

But after adding the faces there initially and having created a geometry in box-view that somewhat reassembled my goal, I apparently used the smooth-view somewhat way too much and created that mess of geometry in box-view.

After countless tutorials of T-Spline modeling, I think I got the hang of the principle, but neither in my head nor on paper I can accomplish to create a structured running of face-loops on the geometry I want to accomplish. That's the state I'm in currently, and my biggest problem is not finding any tutorials creating even somewhat close to these types of shapes. My set goal is to understand T-Splines and to model a beautifully arranged box-view geometry as seen in (very few) tutorials online.

At least I now know what bad design principles in T-Spline geometries are, I know my model is pretty badly designed there, but I'm failing to create my geometry by using these design principles. I know, others would say start easy as a beginner, but I want to learn, and that's why I'm not giving up on this project!

[TrippyLighting]

Yeah, don't give up. All quad faces is definitely good.

When you feel the need to pull vertices that strongly to get the shape you are looking for, then you need to add more geometry. Edge loops! In Fusion 360 you have t-junctions, so Edge loops don't have to traverse the entire geometry.

If you use that judiciously you can create good models.

Watch Sub-D modeling tutorials for Blender, MoDo, Cinema 4D, Maya, 23DS Max. They have a different and often advanced toolset compared to T-Spines, but you'll pick up a number of techniques here and there.

Practice, practice, practice. After a while, it'll settle in! 

[TrippyLighting]

Attached s a first attempt showing *hopefully) how/where to add geometry.

 

 

[Anonymous]

Thanks for your help! I think I'm getting better at understanding all this. Your example file was worth very much for me. I iterated a few times, starting from the loft every time, to get a better geometry. I'm pretty happy with what I created, but even with it looking good for my eye, I can't get it to thicken. The other difficulty that I'm having is the sharpness at some of those edges, I don't know how to insert edge loops there in my design without totally destroying everything.

The design that I want to accomplish however is more of a flow of the edges like shown below:

(not as a really sharp edge, more like what I have accomplished it with the lowest edge, where I think I have an edge loop assisting)

If you could point me in the right direction it would be much appreciated! Attached again where I'm at now, with the button holders inserted where I want them to be. I want to get this kind of stepped arrangement with the two buttons.

The hours iterating really give me some experience and understanding, thanks for every input!

[Anonymous]

It didn't let me off. After watching some tutorials, I saw the usage of triangle-shaped quads to get a corner into a smooth surface. Here is my best try at the method, I'm again happy with the shape, but I think box-view really could look better. I at least now got exactly the edges that I want to accomplish. What could I do better, to get a clean box-geometry as with your design? I meanwhile can create really clean single recesses after getting hang of your method of doing it.

[Anonymous]

After further refining the box-view geometry, I'm at a point where I can't possibly think of better edge flows. I think I have really learned to understand designing free-forms at least somewhat well.

@TrippyLighting Could there be further edges added to thicken/shell a geometry like that or is it simply a limit that is created with such a curvy surface? How bad of a job is my geometry? Thank's so much, your last post really lead me into the right direction!

[TrippyLighting]

This object is not a simple model. I would try to model this again from scratch, probably more than once. Don't add detail until you are completely satisfied with the overall shape.

The area around the buttons is challenging, but should not be refined before the overall shape of the handle is complete.

[Anonymous]

Thanks, I will definitely try that then. I need to accomplish a really clean geometry, that's what I know now. But I think even if I have the basic shape I think I will struggle to get these recesses right/better.