Monoprice Select Mini Owners

Hi, everyone! I got a really strange problem with my Mini V2 printer.

I used the included USB connector to plug it into my Windows 10 desktop, turned on the printer, Windows detects something got plugged in, but once the printer loads up the main UI, Windows disconnects from the printer. I have tried using other USB cables and different computers to see if it was a Windows issue, but it doesn't look like it. The good news is that the SD card works as expected, but the USB seems unresponsive.

When the USB does get detected for the few seconds it lasts, the "device" is labeled as "Unknown USB Device Device Descriptor Request Failed" before it disappears. I am at a loss for words. Does anyone know of any way to fix this issue? I truly appreciate it!

So, I came into a monoprice mini iip secondhand, and it seems to be having some trouble moving the axes. I powered it up, and tried to move the axes from the control panel.

The Y axis almost works. It appears to be commanding the motor OK, the motor under the bed spins. But, the little cable is very loose. If I press the cable with my finger so that it has some more tension on it, it moves the bed OK. Is there supposed to be a tensioner on the belt?

The extruder seems to work fine. Have not been able to test with filament, but the motor turns fine.

The x axis only moves to the right. If I turn the know right, it seems to move, but turning it left, nothing. Any ideas what I might check? Any chance this is a bad cable between the board and motor?

Thanks,

Aaron

You can find the fan mount here: https://hackaday.io/project/171021-fixing-up-the-monoprice-select-mini/log/177071-blower-fan-mount-for-the-monoprice-select-mini

I didn't want to compromise on cooling or visibility of the nozzle, so I designed this mount. Works incredibly well, currently I can get 80mm bridges without issue using PLA.

I picked up a used Mini V2 that was no longer working and thought I would try working on it.

When I turn it on, it flashes the Monoprice logo and firmware version, then goes to the main menu. Then it just sits there. The rotary encoder does nothing. If I hook it up over USB it doesn't show up on the host computer.

I've opened it up and made sure all of the connectors are seated, I homed the axes and turned it on and I tried loading new firmware onto it via microSD (although I don't have small card, I was using a 32GB).

Any other ideas? When I power it up there's a very quick "clunk" like one or more of the motors is engaging.

Anyway, it was cheap and I like a challenge.

I have been printing successfully with my V2 for a few years now. About 15 rolls of material Petg and PLA. Always printer great. Upgrades metal extruder and E3d Lite hotend. I have been printing masks for my son and fellow residents and started to experience under extrusion. The tip of the Bowden tube had shrunk inside the hot end. I had an extra E3d V6 with E3d X nozzle so I replaced the entire hot end. I did a 15 step PID autotune, Calibrated the extruder and releveled the bed. I am still getting random under extrusion and clicking of the extruder. I again replaced the extruder with no difference. I increased the extruder and recalibrated with no difference. I slowed the printing to 30% with little difference. I am trying to print respirator parts using the same g-code file I have printed hundreds of on this printer in the past. Help!!!