Concentric mate issue

[DrBwts]

I have an Assemble that is pretty much the repetition of sliders & cranks. The only difference between sliders is their diameter & the only difference between cranks is the angular offset.

Yet given all the sliders were constructed in exactly the same manner and have exactly the same mates. I can not get the last slider to mate concentrically with the main axis. I'm only using this mate for positioning & all the other comonents did not have a problem. I can manually align it but I cant do it automatically as it complains that the centres are too far away from each other.

What I have tried:
Deleted all the mates & started again... no luck.
Deleted the part and rebuilt it from scratch.... no luck
Rebuilt the whole assembly.... no luck

Anyone else had this issue before?

 

[Jboggs]

What other mates are on the failing part? Are you sure its floating? Are you trying to place two concentric mates on it? I know this isn't your case but for example, when you a have a pattern of tapped holes in one part and pattern of clearance holes in a mating part, naturally all the holes have to line up. A common problem we have seen is when folks try to mate two of those tapped and clearance holes together, it often fails. Usually one concentric and one parallel mate will resolve the issue.

 

[DrBwts]

There are 3 tangential mates, on for each of the slots & a coincidental mate between one of the slider sides and the crank arm.

 

[DrBwts]

OK I dont know why but the order that the mates are done is important. If the concentric mate is applied first then there is no issue applying the other mates.