topic Betreff: 2d closed spline to 3d bodie in Fusion Design, Validate & Document Forum

2d closed spline to 3d body

sjoerdw — Wed, 30 Mar 2022 13:31:06 GMT

Hi,

I did make quite a lot of closed 2d splines and wanted these to extrude to 3d bodies, but unfortunately I forgot to tick the 3d sketch box, so all my splines are just 2d "contour lines" and I can't find a way to convert these to 3d sketches, in order to extrude the enclosed surface to a 3d body. So can anyone help me to achieve this?

Betreff: 2d closed spline to 3d bodie

g-andresen — Fri, 25 Mar 2022 18:31:11 GMT

Hi,

please show what you want to achieve and share the file

File > export > save as f3d on local drive > attach it to the next post

günther

Re: 2d closed spline to 3d bodie

jeff_strater — Fri, 25 Mar 2022 18:47:47 GMT

@sjoerdw wrote:

Hi,

I did make quite a lot of closed 2d splines and wanted these to extrude to 3d bodies, but unfortunately I forgot to tick the 3d sketch box, so all my splines are just 2d "contour lines" and I can't find a way to convert these to 3d sketches, in order to extrude the enclosed surface to a 3d body. So can anyone help me to achieve this?

A couple of points:

check to see whether the "Show Profiles" is checked in your sketch panel:
check that the spline is really all on the sketch plane. Click on the splines and right click. If you see "Move to Sketch Plane" then they are not on the plane. That command will put them there. However, I think you have it backwards. If you want 2D splines, make sure that the "3D Sketch" is unchecked.
If you see a blue shaded area, you should be good to go. If not, then you may have a "leak" in your profile. Use the divide and conquer leak detection method to find the gap and close it

Then, you should be able to Extrude. But, as @g-andresen says, the easiest way to help is for you to share the design here.

Re: 2d closed spline to 3d bodie

sjoerdw — Mon, 28 Mar 2022 17:47:39 GMT

Thanks both of you for the reply. Sorry it took me some time to get back to you, but apparently the forum was down for a couple of days. In the meantime I managed to solve my problem in a way, by retracing the splines (and have the 3d sketch option checked) and luckily fusion did snap to the spline points of the traced spline, so it was a fairly easy job. But anyway I will post the design and a screen print on which you can see an example of a 2d spline which I could not extrude to a 3d body. So maybe one of you can still post a solution from which I can learn! Thanks in advance!

Re: 2d closed spline to 3d bodie

jeff_strater — Mon, 28 Mar 2022 21:46:33 GMT

I think I understand your problem. There is one profile that is not showing a profile. The screencast below shows how to fix that. However, a couple of observations:

You have 4 different sketches. Is that intentional? Why do you need all 4?
Your splines have too many fit points. You can probably get by with 1/3 the number of points in your splines and get the same shape. The more points you have, the slower Fusion will be, and the resulting surfaces will be worse.
You have a lot of warnings in your sketch - all the yellow icons indicate a warning of some kind. Those should not be ignored

The problem for that final profile is the existence of two copies of the spline, right on top of each other. This causes the profile recognition code to fail. I was able to fix the model simply by deleting one copy:

Re: 2d closed spline to 3d bodie

sjoerdw — Wed, 30 Mar 2022 10:37:51 GMT

Thanks for the reply. I did post this version of the design on purpose, because it showed a 2d spline. But for this I had to step back on the time line, therefore the warnings. To solve the issue I retraced the 2d splines, so making indeed copies, and then deleting the "offending" 2d splines. But still the question of how to convert a 2d spline to a 3d body remains...

The reason I did create the shapes in several sketches is simply because I needed quickly one shape to 3d print and to test that shape. Also about the level of detail: the shapes needed tightly to fit into a milled "contra shape", so precision was needed. Anyway thanks a lot for the time spend on my issue, much appreciated!

Re: 2d closed spline to 3d bodie

g-andresen — Wed, 30 Mar 2022 13:22:39 GMT

Hi,

@sjoerdw schrieb:
Also about the level of detail: the shapes needed tightly to fit into a milled "contra shape", so precision was needed.

You can achieve this better if you follow the principle "less is more" when creating splines.
As many control points as necessary but as few as possible.

günther

Re: 2d closed spline to 3d bodie

g-andresen — Wed, 30 Mar 2022 16:35:42 GMT

Hi,

1. position the canvas to the origin

2. Sketch only one profile

3. Extrude the profile

4. Create a circular pattern

watch the screencast, take a look at sketch "new profile" and follow the timeline.

günther

Re: 2d closed spline to 3d body

sjoerdw — Wed, 30 Mar 2022 19:44:33 GMT

Thanks for the reply. I know how to apply the circular pattern mode, but in this case almost none of the shapes are exactly the same. It is hardly noticable, I admit, but it is the case.

Re: 2d closed spline to 3d bodie

jeff_strater — Wed, 30 Mar 2022 20:10:12 GMT

I'm confused by this: "But still the question of how to convert a 2d spline to a 3d body remains..." The screencast shows how to do that - Extrude. But, I wonder whether there is more to your question than this. Do you want something different than an extruded result?

Re: 2d closed spline to 3d body

g-andresen — Wed, 30 Mar 2022 21:21:05 GMT

Hi,

I think it will not have escaped your notice that the reference to patterns was only a piece of information in passing.
The main point is how to deal with splines.
I always find that there is a belief that you get the best result with a large number of control points.
In the attached example you can see that this is not the case and that the interaction of the control points in their distances and the direction and length of their tangents is of decisive importance.

günther

Re: 2d closed spline to 3d body

sjoerdw — Thu, 31 Mar 2022 18:52:37 GMT

Sorry for not getting the point of your message. I did have look at your screencast and indeed it shows a good way to make the splines I was after. But as I did write earlier, many of the shapes do differ from one and another, so I needed to draw them all one by one. But all this was not my core issue. I will later post an example of what was exactly my issue.

Re: 2d closed spline to 3d body

sjoerdw — Fri, 01 Apr 2022 17:40:16 GMT

Well, after making a design to show my issue, it turned out it was due to my (still) lack of knowledge of Fusion. When sketching with a spline, all "features" were turned off (see attachment), so I could not extrude the shape to 3d. I thought it was due to not ticking the 3d sketch box, but now I know I had to tick the profile box. And yes some of you mentioned it already. So sorry for the confusion, but all this was still very instructive for me. Thanks for the input!