Jump to content

adding or subtracting screw thread often "cannot be computed"

Recommended Posts

Have others come up with this issue? I often need to create a solid with internal or external screw threads. Having created the thread, when it comes to adding or subtracting sometimes it works, other times (and more often that!) I get the "You're creating an object that can't be computed" message. After a fair bit of messing about I can usually work around, but today the frustration got a bit more. Perhaps others have had this and have an answer? (VW 21)



Link to comment

Now I'm both impressed as well as puzzled. Intersecting, how? I've set it up following standard thread pitch values, unless the issue is one of those ".0001" changes and everything works. You've alerted me, I'll play away.

Many thanks. 

Link to comment

I think Virtual Environs is correct that it is intersecting geometry.  I think somewhere in the sweep, the "back" corner of the profile polygons are overlapping.


I slightly "sloped" the back edges "down" to make the back edge slightly smaller and then the sweep and the shaft were able to be Added.


image.png.738bee17e5e0a1971636fc4ab91fa607.png Original

image.png.8d9db931ba7f9f437989cba62764331e.png Modified


Vectorworks really does not like having overlapping geometry in the same object.

  • Like 1
Link to comment

Late to the party, but is this something that could be solved using the tapped hole tool from the Detailing toolset?  It is a tool I never use because accurate thread geometry is rarely important to me in my modeling, but it seems that Vectorworks may be more amenable to geometry that was created in Vectorworks.

Link to comment

You've given me plenty to play with and see but not had a chance to try it yet - small business and I'm chief cook and bottle washer. I have noticed that on occasion VW says it doesn't like something that you believe to be correct. i.e. the infinitesimal alteration and VW is now happy. But have taken on board all the suggestions and probably have a go later today. fighting the resulting 3D prints at the mo. I'm wondering if it might be internal rounding errors, hence my previous thought.


Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...