Page 1 of 3 123 LastLast
Results 1 to 10 of 23
  1. #1

    Roll bend problem

    I have to model a roll pin that has a zig zag split line. I can make the part but when I try to reduce the bend radius it fails.
    Click image for larger version. 

Name:	Capture.JPG 
Views:	9 
Size:	56.3 KB 
ID:	6735
    Here is the part with a 3 mm bend radius which is about as small as it will regen. I need to make it 2.375 mm. At some point under 3 mm I believe Pro/E thinks it starts self intersecting although it really doesn't because the notch and the tab are the same size. It can really close down to 2.25 mm radius. Any ideas on how to get this to work?
    PTC quality philosophy: We've upped our quality standards. Up yours.

  2. #2
    So I tried redefining my bend from a roll bend to an angle bend. This works better but not there yet. Since you can only bend up to 360 degrees, there is some of the tab left unbent. Maybe I can do it with 2 bends.
    Click image for larger version. 

Name:	Capture.JPG 
Views:	3 
Size:	42.8 KB 
ID:	6736
    PTC quality philosophy: We've upped our quality standards. Up yours.

  3. #3
    Have you tried a torroidal bend? I've used it to make tires and it works really well. This sounds like a part accuracy issue to me. It shouldn't matter what size it is if the accuracy is set to the proper size.
    Last edited by CPiotrowski; 11-19-2015 at 07:05 PM.

  4. #4
    So two bends is the answer, at least the best I've found. It looks OK to me.
    Click image for larger version. 

Name:	Capture.JPG 
Views:	4 
Size:	35.3 KB 
ID:	6737
    PTC quality philosophy: We've upped our quality standards. Up yours.

  5. #5
    Quote Originally Posted by CPiotrowski View Post
    Have you tried a torroidal bend? I've used it to make tires and it works really well. This sounds like a part accuracy issue to me. It shouldn't matter what size it is if the accuracy is set to the proper size.
    I did not try a torroidal bend, I've almost never used that feature, the interface seems to be one of the most cryptic imaginable. Does it take bend factors into account the way sheetmetal does? It's not an accuracy issue, no small surfaces. Pro/E has some build in limits on certain things like no more than 360 degrees in a bend, etc.

    You have piqued my interest, torroidal bend here we come. The two bend approach has it's drawbacks such as the need to write relations to keep the bend radii the same.
    PTC quality philosophy: We've upped our quality standards. Up yours.

  6. #6
    It bends based on a selected trajectory and the overall length of the sheet being bent. It can be difficult to figure out initially but once you get the hang of the feature it is very powerful. What would take hours to do with sweeps or solid modeling when referring to making a tire, torroidal bend can do in a fraction of the time and more accurately.

  7. #7
    So I made a toroidal bend but I don't understand what it did. The bent part is much bigger than the unbent part. My sheetmetal part has a radius of 2.375, the toroidal bend came out with a diameter of 8.98. I put the sketch CSYS where I expected the axis to be (help is most unhelpful about this) but the axis is nowhere near there.
    Click image for larger version. 

Name:	Capture.JPG 
Views:	3 
Size:	81.5 KB 
ID:	6738
    PTC quality philosophy: We've upped our quality standards. Up yours.

  8. #8
    Well. I got the radius figured out, non-intuitive as hell, typical PTC. However, you can't have any geometry that goes beyond 360 degrees so it won't work.
    PTC quality philosophy: We've upped our quality standards. Up yours.

  9. #9
    You shouldn't have to go past 360 degrees. If you were to remove the tab that sticks off of the rectangle when flat and then roll it...it doesn't have to go past 360 degrees. When you sketch the roll pin...you add the tab to the end of the rectange (past what is designated as the start or finish) on one side and add the cutout on the other. When you wrap it 360 degrees you should see exactly what you want. And you're right...its not intuitive at all and takes some practice to get it down.

  10. #10
    Well see if you can get any overlapping geometry with a toroidal bend, I could not get it to. I tried with the start and finish not including the tab but as soon as I increased the angle to where the tab got close to the start it failed. Somewhere around 330 degrees in my part. The two bend sheet metal approach is working. Thanks for your help.
    PTC quality philosophy: We've upped our quality standards. Up yours.

Page 1 of 3 123 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •