topic Re: How to match an extruded form to a sketch curve in Fusion Design, Validate & Document Forum

How to match an extruded form to a sketch curve

sweiner29 — Sat, 07 Oct 2023 06:30:35 GMT

Hi. I'm stuck modeling a chess knight. In the attached picture, I'm trying to match the bottom edge chain to the base (a circle sketch), which I am hoping will blend the base nicely into the existing form. However, I keep receiving an error about selecting multiple edge chains, and can't figure out why that is. I am open to alternative modeling methods, but if I can get this operation to work, I think it will give me exactly what I need. Thanks.

Re: How to match an extruded form to a sketch curve

TrippyLighting — Sat, 07 Oct 2023 08:48:51 GMT

Would you have an image of the final form you are trying to model?

the form you have modeled so far violates most of the good T-Spline/Form modeling practices already, so you are better off starting from scratch.

Here are my few T-Spline Guidelines with a few links at the end:

1. Model 80% in box view mode. The shape should somewhat resemble the desired, smooth end result. Make small adjustments in smooth-view mode. Check back in box view mode to make sure the model still has integrity. Faces should not intersect in box view mode!

2. Do not add detail until you are 100% satisfied with the overall shape and proportions of the shape. The more detail you add the more geometry you have to manipulate, usually resulting in a lot more work than necessary.

3. Avoid triangles at all cost until you are at least at an intermediate level with T-Spline modeling. Triangles are best avoided altogether.

4. Limit the use of N-gons (polygons with more than 4 edges/vertices) to the bare minimum. No N-gons with more than 5 edges vertices.

5. Start with as little geometry as you can get away with. Add more as needed. If you find that you need to stretch polygons too much to get a desired smooth shape, then you need more edge loops/polygons.

namenotimportant

Arrimus 3D

Gichi Endo

Re: How to match an extruded form to a sketch curve

sweiner29 — Sat, 07 Oct 2023 16:39:37 GMT

Hi. Thanks for your response. I undid the fill hole operation which seems to violate some best practices. As far as I can tell (with the exception of box mode) this cookie cutter shape follows these guidelines. I want the edges at the bottom to match to the circle sketch. I've included the reference image for you as well.

Re: How to match an extruded form to a sketch curve

davebYYPCU — Sun, 08 Oct 2023 21:13:27 GMT

Trim an airgap from the base of the top section, try Bridge in form tools, or Loft.

Might help....

Re: How to match an extruded form to a sketch curve

sweiner29 — Sun, 08 Oct 2023 21:19:00 GMT

Will give it a shot tonight. Thanks.

Re: How to match an extruded form to a sketch curve

TrippyLighting — Mon, 09 Oct 2023 01:31:04 GMT

Here is how I'd approach this.

The video will take a while to convert on YouTube:

https://youtu.be/4OvqjH8zJS4

Re: How to match an extruded form to a sketch curve

sweiner29 — Mon, 09 Oct 2023 02:46:38 GMT

@TrippyLightinglooks fantastic. Thanks for putting together that video. It will probably take me a bit to decompose it all, but I like the loft option. In the video you mentioned that you normally like to use Blender for this. I've heard similar from others. I've considered it, but was hesitant because the overall workflow was unclear to me. Do you think the time for me to research and adopt a Blender -> Fusion workflow would be worth the time investment?

Re: How to match an extruded form to a sketch curve

TrippyLighting — Mon, 09 Oct 2023 11:24:06 GMT

@sweiner29 wrote:

... In the video you mentioned that you normally like to use Blender for this. I've heard similar from others...

I have started working with Blender starting around 2003 or so. So over 20 years. In my experience - I hear such recommendations a lot on the Fusion 360 Facebook group - the vast majority of folks that recommend to use Blender have heard that Blender is "better" and might have watched a tutorial or two. But they have never modeled a thing in Blender that is similar to the geometry that they recommend Blender is better for!

Blender indeed has many more modeling tools than Fusion 360, but for a Beginner T-Spline modeling in Fusion 360 is more intuitive. So I'd stick with it for a while. Some tools in Fusion 360's T-Spline modeling are better than in Blender. Circular Symmetry I find is one of them. You cannot match a T-Spline edge loop to a curve etc.

However, I always recommend for folks to broaden their modeling skill set. As such, Blender can make a very powerful companion to Fusion 360.