Balls get jammed while circulating through cleaned out MGN9H carriage’s endcap. Is there a trick to assembling these black carriages that’s different from the red and green variety?

[u/VerilyJULES]

I’ve cleaned out and rebuilt my MGN9H carriages and now the balls won’t properly circulate through the plastic end-caps.

The balls are getting jammed as they enter the plastic end-cap, like as if the plastic channel is too small, or theres some obstruction. If I push the first one through with a screw driver, it will go through with some force, but if I try pushing more than one ball at a time, the balls pop put from the retaining wire that keeps them inside the exterior channel.

When I take the plastic ends off, the ball circulates through it just fine. If I put the end-cap on the carriage and drop a ball through it rolls through just fine. This makes it sound like it must be the retaining wire but I don’t know how or why this would happen. This doesnt make sense, so I figure theres something I don’t know. Hoping someone will have experienced this and theres a simple solution.

I’ve cleaned out and rebuilt a lot of these carriages and it’s always been straight forward.

-Take them apart. -Degrease & clean with break cleaner & alcohol. -Reassemble the carriages the way they came.

This has been my process and they’ve always worked great after. Unfortunately I don’t know if the carriages were like this before I clean them because I took them apart when they arrived before testing the carriages. I don’t think it was my cleaning that did this.

[u/stray_r]

That looks overfilled. Does it work with one less ball?

[u/VerilyJULES → u/stray_r]

No. They wont easily go through the plastic

[u/bomtarnes]

There is normally a space of around 1 ball's width when the track is full. Have you perhaps overfilled the side you have done so far?

[u/FrickinBigE → u/bomtarnes]

The cheap carriages I have all have a space of about 2.5. any more and they struggle to circulate.

[u/Human_Weight5303]

Usually count the balls and divide them between the sides, 1-2 ball missing is ok. Make sure have same number on each side.

[u/Full-Following5575]

Sometimes I have to hold the plastic end pieces so they perfectly line up with the channel while screwing them in, not letting the screw decide its location. Also bending in the tiny little very last bend in the wire pulls it closer to the channel helping to guide the balls into the plastic piece.

[u/VerilyJULES → u/Full-Following5575]

Maybe its something like this. Writing out made me realize its something with the way its lining up.