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ST8 Circular cutout pattern on a circular sweep

Experimenter
Experimenter

Hello everyone,

 

I am new to this forum and I would describe my CAD skills as beginner to intermediate.

I am currently working on a project that will use the shape / curvature of an imported STL as a basis.

After constructing a tube out of it, I would like to pattern a cutout around it (circular). As a next step I would like to pattern this pattern along the long axis of the sweep. However the problems already start with the first pattern command. It gives me the prompt: "System Error encountered during evaluate".

SE Capture.JPG

 

SE2 Capture.JPG

 

I can't come up with what I am doing wrong.

The final solution should look similar to this one:

607483140.jpg

 

I am aware that the diamond as a starting sketch might not be optimal.

However, I wanted to start with a "simple" approach. I am also afraid that I will run into problems when doing the pattern along the long axis, so that the strut will not intersect each other at each new pattern/stack.

I am hoping that someone can help me out here. Or maybe even have a better idea to approach the overall problem.

Thank you in advance.

Julius

 

5 REPLIES

Betreff: ST8 Circular cutout pattern on a circular sweep

Gears Esteemed Contributor Gears Esteemed Contributor
Gears Esteemed Contributor

Hi @Julius and welcome to the SE forum!

 

 

First of all let me ask "Would a real Circular pattern work for You?"

 

The pattern You have used - according to the image - is a Curved Pattern and not a Circular one.

 

Another issue could be -- hard to say without having the real part in front of You - which objects are needed for the cutout feature itself.

I can see a couple of sketches there and would assume, that You have used one o rmore of them too.

So it could be, that they also must be included into the pattern, but I would see this not as the best way to get the result.

 

Another option to improve the result could be a switch to a fast pattern rather than a smart pattern

 

Hope one of the hints will help to get it

 

 



regards
Wolfgang

Betreff: ST8 Circular cutout pattern on a circular sweep

Experimenter
Experimenter

Hi @hawcad,

 

thank you for the help, and sorry for the late response.
I used the other pattern command now. In the end it worked with a smart pattern. The fast option gave me an error.

Capture3.JPG

 

However, trying to use the curved pattern, for a pattern along the long axis gives me the same error as before. I attached the file, so that it easier for people to help me out here.

 

 

By now I also suspect that my approach will not work properly (not just because of the "**bleep**ty" sketch"). But also because it should result in thin struts, connecting to each other. However, given the static sketch and dynamic diameter of the tube and the curvature I will likely run into some problems:

- Not intersecting or "overlapping" parts of the pattern due the curvature.

- On spots with smaller diameter the sketch itself will overlap or the pattern command is impossible to use.

 

I guess I would need a dynamic sketch that stretches the "diamonds" according to the position of the tube (if it is placed on the inner curvature or the outer one). Furthermore it would be more meaningful to have single "stacks" of one circumambulation that are placed normal the centerline of the tube in certain distances. Each of the stacks is not connected until then. There it would be sufficient to connect each of the stacks by 4 struts. Since these connections will have different lengths depending on the curvature, it would be good if this could be automated by marking the connection points.

But: I got absolutely no clue how to do that and I also guess CAD programs are not made for this. Maybe more "powerful" programs such as NX or Catia?

 

Does someone have a better approach, especially with regard to rapid and easy adaptability to new shapes and diameters (customization)? I am thankful for every piece of help! Smiley Happy

 

Best regards

Julius

Betreff: ST8 Circular cutout pattern on a circular sweep

Gears Esteemed Contributor Gears Esteemed Contributor
Gears Esteemed Contributor

HI @Julius

 

 

 

let me give another hint or suggestion for modification.

 

 

As far as I can see, You have started Your diamnond cutouts with a connection to the outer surface.

 

So make this end of the tube longer a shot length, that the diamond can be copletely inside the tube.

I can imagine that then the pattern will be a fast pattern.

 

Afterwards create a cut or use substitue surface to shorten this end again.

 

Using this "trick" You can use fast pattern nearly always and so You will improve and increase the part performance.

 

Give it a try!

 



regards
Wolfgang

Betreff: ST8 Circular cutout pattern on a circular sweep

Experimenter
Experimenter

Hi @hawcad

Actually it is not directly connected to the end of the tube. It was in an earlier stage, and then it did not work at all. I used a 0,01mm long construction line to offset it.
However, now I tried to simplify the whole design to test whether I can get the curved (along the long axis) pattern get working. In this approach I used a costant cross sectional diameter (15,55mm). While doing this I increase the construction line's length to 0,1mm and the the smart option worked as well. Is 0,01 too small and will be neglected? Thanks for the hint.
But I was still unsucessful with the pattern along the long axis. I just cannot get it to work. It gives me the same error over and over again, regardless of which option I try. I also attached the simplified file, in case you have time to look into it.

I was also thinking about diving into the API of SolidEdge to program a kind of a macro that will just let me specify the points where each of the "stacks" should be located and measure the diameter there in order to have an adaptive solution (amount of pattern will be adapted). However, I still do not know how I would connect those stacks at certain points without massive manual work (Refer to this photo to see what I mean)

Rebel-stent.

 

 

My aim is to automate it in order to make it feasible for customization. Nonetheless the problems already started with the pattern. (The API of SolidWorks would be possible as well in case it is easier to educate myself in that due to information material; no offense Smiley Very Happy)

 

 

Betreff: ST8 Circular cutout pattern on a circular sweep

Gears Esteemed Contributor Gears Esteemed Contributor
Gears Esteemed Contributor

Hi @Julius

 

 

 

what I just that moment got as inspiration is, what's about to transfer a part of that job into an assembly.

 

Creat one "ring" body - as You already have done it so far.

Put this one into an assembly and do there the pattern along curve.

Or same idea and simimlar setup, with one body and a pattern of taht body, but this time in one part document - hint; "Multi Body Design"

 

So You can avoid the non manifold body situation in which the feature pattern can come somehow.

 

And besides this, with the ASM approach I think You will improve the performance really a lot, increasing speed and reducing time to process Your design.

 



regards
Wolfgang