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Spring Mechanism


New member
I am trying to create a model of the rear suspension
to a mini-baja vehicle, but I am getting stuck on the shock. I
can succesfully make the shock and the spring, and can make the spring
flexible. The problem I'm having is once I have everything
defined, I can not enter Mechanism without getting the "This connection
is not defined by two body's error". If anyone has any
suggestions on what I can do to solve this problem it would be greatly

Thank you,

Jim Giacchi


New member
doesthe message that u get prompt u to continue and then suppresses some parts off the assembly?

i think this has to do with the types of constraints u r making, i had a similar prob once.
go over the assembly constraints and make sure any part is roughly constrained, pick the right connections for the intended mechanism and make sure u dont constrain any part to the default location

hope it helps

Edited by: shadshood


Active member
your assembly connections are not correct. If you can send me your files ,I will fix it and send the solution to you.


Luis Aguirre

New member
Alot of this type of pronblem in mechanism can be solved by simply
using topdown design techniques which include the creation of and
skeleton to assemble your parts.



the references for ur parts mechanisms connections are wrong.


pin ccylinder.. etc

these have to be referenced to the 1 part u can not select multiple parts to reference off otherwise u get that error.

if u still have trouble i can a have a look @ it for u

---- out of interest. how would a top down design stop this error from happening?

Edited by: puppet