1

Just started to assemble Anet A8, not got very far but I have a question.

It’s about Part #1700300002 - Y Axis Belt Bearing Support

This comprises two acrylic sides, a nut and bolt that form an axle and two metal wheels which I assume will create a roller for one of the belts.

The two metal wheels have a bearing inside so I’m assuming that once assembled the wheels/roller are meant to rotate freely.

My dilemma - if I tighten up the nut and bolt the acyclic sides clamp against the wheels stopping them from turning. If I leave the nut and bolt loose then the wheels turn but I guess over time the nut and bolt will work apart.

Assuming the wheel/roller is meant to rotate freely I can think of two approaches

1 - Leave the nut and bolt just loose but add a locking nut to stop the assembly working apart

2 - Insert small washers - the diameter of the inner of the bearing - and tighten the nut and bolt. The washers should keep the acrylic sides off the wheel outers allowing them to rotate freely. Even with this I would be tempted to add a locking nut or use threadlock.

Anyone else encountered this and how did they solve it?

And in general do you use threadlock on all the nuts and bolts - given how much the printer will move and vibrate it would seem a good idea to me but you guys may know better.

Thanks for the help,

Nigel

2

I went ahead and added a small washer either side of the pulley wheel. The pulley wheel now turns smoothly.

Cheers,

Nigel

3

Your solution also works, so keep it.
What I did: I added a second nut and tightened it to the first one. It never got loose.

But if your solution works, go with it. Just check the nut from time to time.

4

You’re probably over-thinking this. FWIW, I have never had any of the nuts come loose - just be careful not to over tighten anything since this can cause things to snap…