Reverser - Threaded Slider joint with motion link and another sliding joint

[Doubletop_]

I'v attached my project. The screw rotates and the die nut runs along the thread. The motion link combines the two and ensures the distance travelled relates to the screw pitch. The problem is the die nut rotates with the screw. The design has a 'shoe' that runs in a rail but any attempts to make this a slding joint gives  the joint conflict message an no clues as to why.

I've tried a motion link to try to combine the two joints with no luck. Ive tried applying the joint for the shoe before the threaded joint, also no luck. No doubt a simple solution but I can't find it Im afraid.

(Joint Cyl18 and Motion Link 19)

Thanks

Pete

[hamid.sh.]

Your file is not attached. Wait for the upload to finish before clicking Post.

[Doubletop_]

I'm sure it was attached as I attached it before I started typing. Attached now?

[jhackney1972 · Accepted solution]

Add a Planar Joint between one of two sides of the guiding foot on the nut.  I also reversed your motion link, it was going the wrong way.  Model is attached.

[Doubletop_]

John

Thank you. I lost count of the times that I tried the same joint as a slider, because that is all the joint is doing. Selecting planar was counter intuitive as it says "component moves along two axis and around a single axis". As far as I was concerned that joint just needed to be a slider as "component moves along a single axis". Using the planar link in my model here worked first time.

Your comment that the motion link was the wrong way round, was that because you though the die nut was going in the wrong direction when you turned the handle? The thread is left hand.

Where do you find the definitive guide to joints. All the online videos just seem to cover simple cases. For example it took me ages to find a link that showed me how to make the screw thread function correctly. Most examples were  very basic..

Thanks again

Pete

@jhackney1972 @hamid.sh. 

W

[Doubletop_]

@jhackney1972 

I've sorted the motion link. Yes I did have it going the wrong way

Thanks again

Pete

[jhackney1972]

I do not think you will find a text covering “combination” joints, these boil down to understanding of the model geometry.  I too would consider a Slider joint but then I would have to consider the screw joint axis.  That joint already forces the nut to move in a straight line so adding another joint that does the same is bound to be a conflict.  A Planar joint will force to surfaces to slide on each other in all directions on a plane without imposing a straight line motion.  

[Doubletop_]

John

Even your explanation helps. Understanding the interelationship of joints is the key and the error messages aren't that helpful nor is the detail. The descriptions in the online documentation aren't that clear.

However, I've just found this that may be what I'm looking for

Pete

(@jhackney1972 )

[jhackney1972 · Accepted solution]

NYC/CNC puts out some good work so I am sure you will pick up a lot here.  I however want to emphasis every assembly joint requirements are different.  My best advise is to think in terms of real life geometry and match up the needed motions using joints remembering to try and not overlap.  Your assembly was unique in its joint needs and it is easy not to look at the total motion situation.

[Doubletop_]

Appologies I thought I had accepted the solution. It all works fine for me now

Pete