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part creation in assembly mechanism


New member
I am facing a problem in WF2, (Assembly mode)

If i activate a part in the assembly mode and assuming that this part contributes in a mechanism (i.e dragging it with the handle makes motion) , then i create a simple feature in this part extrude feature and caring that all refrences i took are from the part not from any assembly refrence

after doing so and trying to drag this part i found extremely unwanted parts motion

could any body help ? i believe that its a reference problem but i cant cure it


Active member
Pro/Mechanism is very sensitive to assembly or part changes. I advice to make your assembly first and then create mechanism connections/drivers. Joint axis setting, snapshots, and motion analyses all are disturbed with post-mchanism changes.


Uni Phil

New member
Have you fixed the base part so that it doesnt move, and have you gone back into the connections of the parts that move wrongly and looked at weather you have any connections with warnings.

Try regening as well after you create a part in the asm. I find this can sometimes be the difference between something working and not working.


New member
I'm just gettin ginto Mechanism Design myself so after one of PTC's webcasts by John Peng, I asked him what was the best way to to actually create components for mechanism and he said to create a fully constrained model (he was talking about Top Down design and Skelletons at the time also) then to

" consider doing a copy of the top-level assembly and on the second one, redefine the moving components off of the skeleton to incorporate Mechanisms and then BMX.
<DIV>Always good to have a before and after version of your design in case you need to make changes. Please note do not change the names of any of the parts, justthe top-level assembly would have different names. You want to maintain the associativity if your components have changes." </DIV>
<DIV>hope this is of some use..</DIV>
<DIV>James </DIV>