Howdy howdy howdy,
I’ve been chasing some inaccuracies in the x/y planes and re-printed the core clamps. Sure enough, I had cracked one of them during the install. Put on 4 new ones with kid gloves and I still have a little wiggle in the core. So off came 1 of the clamps and sure enough again, 1 of the little cones was deformed. So it looks like the core bearings can recess too far and leave some free space between themselves and the conduit. I was trying not to gorilla things during assembly but I apparently failed and will need to print an entire new core. But before I do, just looking at it it seems the there is a fairly fine line between not enough and far too much. Crossing to 1 side appears unfixable short of replacement. I see no way to take the pee out of the swimming pool 
Wouldn’t it be better to replace those 4 crushable spacers with just a metal washer of appropriate thickness? It would still be possible to go full on hulk and destroy things but it seems it would give a much broader range of ok before that happened.
Or is there a different reason that I’m looking right past?
How many perimeters and are you using the recommended infill? I cracked a core clamp but have never seen any compression of the “spacer” features on my build. Some photos might also be helpful.
I printed the core… a year ago maybe. I’ve had the parts sitting in my desk for ages and finally got off my butt. I don’t remember what settings I used other than I did the infill %'s based on the parts list. I’m going to be going fairly thick on the re-print though. The makerspace just got a bambu so I’m going to tie it up, but not nearly as long as it would tie up my ender. That bambu is nuts.
I’ll have to take the clamp off again to get a picture. But on the core there’s a little pyramid’ish spacer that the bearing sits against. Currently I can rock the tool slightly on both axis. I’ve measured the tubes and they’re the correct size. I think that not so pyramidy looking part being crushed a bit is letting the bearings sit deeper into the core than they’re supposed to sit. And I’m looking at 1 tension bearing on either axis that isn’t quite making the same contact as the others. Sorry for the technical jargon :laugh: I’ve re-printed the core clamps, installed and re-installed, and in doing so noticed I had the bolts for the clamps backwards which probably made me crush things instead of snugging the nuts. As I was reading again the instructions I found note to be careful to not mess them up, and I had already messed them up.
User error, so I’m going to re-print the core. Yay. I picked up some 1/4" washers from HD and they fit almost exactly inside the outer rim of the bearings. I haven’t measured their thickness yet but I’m guessing a slightly modified core + a washer would pretty much eliminate the issue on future builds.