Just added washers - all smooth now.

Here is a close-up of the “J1 turret platform” on the ”J1 turret housing”.

I noticed it is grinding , and the aluminium “dust” is building up and likely what is making the grinding progressively worse. The current assumption of the next step is to disassemble and add a shim.

Has anyone experienced this, what was your solution? Have I done something wrong somewhere?

I’m also experiencing issues with J1 turret locking up.

When initially completing the turret it worked fine, but now during operation it sounds like something is grinding and it is getting worse to the point it can seize.

@gkosin302 where did you add the shim? Could you please add a photo of what you did?

I had the same problem with the aluminum parts kit I received in the last month or so. I corrected it by making a shim approx .6mm thick and re assembled and now it’s good.

Can shoot video or photo put here?

Thank you for your reply. I saw the videos as well. Also, I assembled this several times. However, it is locked when I screwed the (8) M6 X 14 socket head cap screws. I think the spindle dimensions, especially its height and J1 turret platform are not very accurate. I bought the aluminum kits from Annin Robotics. The only way is to put the (4) M4 x 10 set at a special distance from the bearing and not tighten (8) M6 X 14 socket head cap screws. However, in this way, the (8) M6 X 14 socket head cap screws can be rotated by hand. What is your opinion?

I think hardly have problem at J1, sure you make mistake. try watch videos from here. There is 40 videos there regarding AR3. J1 issue in first few video. The walk through very detail and clear.

https://youtu.be/Sjv8fxr5LJc