I recently picked up a Monoprice Select Mini and have been extremely impressed. After a number of stuck prints and an inherent desire to mess with things I decided to upgrade to a glass bed.

I didn’t have any exposure to 3D printing before going with the mini and can say that it’s a great starter printer. I’ve been able to learn a lot with only experiencing a few mild fails in the months since I got it. One of my annoyances was that my prints would get extremely stuck to the bed after printing and I got tired of replacing the tape every 4 or 5 prints. It sounded like glass was the way to go so I ventured a trip to Lowes and grabbed some.

Note, I did not get borosilicate glass. I know it has better thermal properties and is a superior product.

I read a few opinions on various forums where folks have said that it’s only really needed if you’re printing 80C and higher. I plan to go no higher than 60C for PLA and decided a $2.50 experiment with regular glass be worth the risk. If this turns out to be a bad idea I’ll make another post and/or become vocal in ‘borosilicate’ vs ‘regular’ threads. I’m also not printing non-stop or doing extremely long prints so take that into consideration.

Step 1: Print the Glass Bed Spacer

The Monoprice Select Mini Glass Bed Spacer by Sumpy (Thingiverse) printed perfectly for me with supports. It clips on easily and activates the endstop switch on the Z axis sooner to compensate for the glass. It printed out at a 3/32” thickness practically identical to the glass I purchased.

Glass Bed Spacer. Once printed set aside.

Step 2: Disassemble the printer

We need to access the back side of the printer so we can attach the spacer. Unplug the printer and lay it on flat on a solid surface. Unscrew the six screws on the bottom and set aside. Be careful as the main board is mounted to this plate. It can be rotated and moved out of the way without unplugging anything for this procedure.

Unscrew the three screws that hold the back plate on. Be extra careful to not lose the washers!

Reattach the bottom plate (I cheated and only used two screws) and set the printer back upright. Remove the three screws holding the back plate on. Again, don’t lose the washers!

Pull the back plate directly back towards you to remove it. You can see the Z endstop switch near the mounting hole for the filament holder.

Z endstop switch

Step 3: Attach the Glass Bed Spacer

Attaching the glass bed spacer is fairly simple. I started at the bottom, hooked it on the front, and then pushed in on until it clipped in to place. See below:

Glass Bed Spacer in place

After the bed spacer is in place reassemble everything and you’ll be ready to attach your glass.

Glass!

I removed the existing tape and cleaned off the remaing residue with Goo Gone. Then I went to my local Lowes and had them cut some glass for me. I had them cut it roughly 130mm by 140mm. I also stopped by my local MicroCenter and picked up a couple packs of Heatsink Thermal Pads. I have to be honest in that I’m not 100% thrilled by the pads, but they seem to have done the trick. Check the reviews on Amazon; a few of the pads didn’t stick well and go along with what folks have complained about.

I placed the glass onto the bed and placed binder clips all around to squeeze it onto the pads (not pictured). After ensuring everything was level and the distance from the extruder was good I removed the clamps and set out to reprint another bed spacer in case the current one cracks (backup parts are the best parts!).

Glass Bed Spacer

So far, so good– though it has only been one print so far. Time will tell if this was a good idea or not.