Constraints Help Needed

[TJT]

Good Day everyone. I have a question about constraints. I am modelling a reversing screw with a follower to guide a carriage. I am having difficulty in figuring out how to constrain the follower to double helix. If anyone knows of a video or a forum topic that will help me out I would appreciate hearing from you.
Thanks
Jim

 

[HaroldL]

Please upload your assembly as a Package file so it includes all its components. (File>Package>Create).

 

[DavidJ]

There might be parts of this video that are relevant.

 

[JimCad]

Very good video.

 

[TJT]

Harold thanks for the tip on attachments. Haven't gotten around to the video yet but will tomorrow. Thanks DavidJ

 

[DavidJ]

I don't see for sure how you'd properly constrain the follower, but for the rest;-

1. Fix things in the workspace to stop them 'floating around'. I typically either constrain or anchor my first / major part (perhaps the side plate in this assembly).
2. You can set motion limits for the carriage travel, to keep it withing the threaded region of the screw.
3. Try 2 screw constraints (one for each direction of motion, but otherwise identical)

For the follower - you could set angle constraints to get it pointing in correct orientation then use configurations to match the correct angle with the direction of movement.

This is one of those non-standard things that won't 'just work'.

 

[TJT]

Thanks DavidJ. I tried to use the screw constraint and didn't have much success with my Model, although when I drew a bolt and nut I got it to function. I think I will just 3d print and test out my design. It will be much faster than trying to do it in a model. Maybe someone who is well versed in Alibre will take on the challenge.