Welcome to the Onshape forum! Ask questions and join in the discussions about everything Onshape.

First time visiting? Here are some places to start:
  1. Looking for a certain topic? Check out the categories filter or use Search (upper right).
  2. Need support? Ask a question to our Community Support category.
  3. Please submit support tickets for bugs but you can request improvements in the Product Feedback category.
  4. Be respectful, on topic and if you see a problem, Flag it.

If you would like to contact our Community Manager personally, feel free to send a private message or an email.

fixed chain/belt setup (not a loop)

david_lang457david_lang457 Member Posts: 68 ✭✭
I am trying to model a couple different setups where the belt/chain is not a loop (so the belt featurescript doesn't work)

one example is a belt/chain anchored on both ends that has a motor on a mobile item in between (cheap laser cutters do this with belts, but the same thing happens with automatic gates)

the other example is a corexy ( https://corexy.com/theory.html ) that is used on high speed 3d printers. The belts are anchored at the carriage in the center at both ends.

Also, with the belt featurescript, I can do a design-in-context from my assembly, but then when the assembly changes (configuration changes), the belts created do not get changed to match

there is a sample of this at https://cad.onshape.com/documents/af00bd1e0c2361197d31a0e4/w/6b41b669b7a601ad14ae5141/e/43ac694c0ba9a79e9cbc6d2f (see the two sample tabs at the end)

while I can model it manually, it would be fantastic to be able to define a belt that remained paired with the pulleys as the assembled parts move (the yellow part can slide on the rail in the example above

I could do this by doing everything in a parts studio, but that gets a bit ugly as I have to have lots of duplicate parts, can't insert standard hardware, get a good BoM, etc


  • david_lang457david_lang457 Member Posts: 68 ✭✭

  • david_lang457david_lang457 Member Posts: 68 ✭✭
    example of the belt routing I am talking about. the blue belt gets anchored at the ends
  • glen_dewsburyglen_dewsbury Member Posts: 352 ✭✭✭
    edited September 10
    You could you add a position variable in the var studio that will adjust the loop position in the belt part studio and the assembly via a position mate using the same variable. This will not animate the assembly of course but let you check at al positions. In particular the extremes or any place there might be interference with other components.
    If your looking at frame size changes, I think the same will apply via a calculation.
    The total belt length will also be calculated as well.
    Make sure to check the box in var studio that inserts into all part/assembly studios.
Sign In or Register to comment.