[Igneoustoast]

Hello Everyone,

I recently bought a used LittleMachineShop mill off of eBay and I have encountered chatter inside of what seems to be the power transmission box. The spindle spins fine, however, there seems to an occasional chatter and I do not know what it is. I have linked a video of the machine in use:
https://imgur.com/gallery/nT5MuCU

I am new to machining and am cautious of wanting to open it up out of fear of further damaging the machine. I wanted to consult with anyone to see if anyone has had this issue before and how to fix it, before I go and open it up.

The specs of the mill are as follows, as well as linked in this imgur post.

Mill specifications:

Model: 3990 HiTorque Mini Mill
Spindle Motor: 0.67 Horsepower (500 Watt)
Spindle Taper: R8

Mill specs: https://imgur.com/gallery/Dl1544W

Power transmission box in question: https://imgur.com/gallery/28suKq4

[awerby]

There should be a belt drive in that power transmission box. It could have a loose pulley, a bad bearing, or a fraying belt that accounts for the noise you're hearing. I don't think it would hurt to open it up and take a look. Just remember how it all goes back together...