Metric: 16cm x 13cm w/ 45° off each corner (13mm).
Inches: 6-1/4“ x 5-1/8” w/ 45° off each corner (1/2“).
Amazon.com - 130mm X 160mm, 3mm Thick Borosilicate Glass Plate Bed, Select Mini with Corners Cut
Amazon.com - 130mm x 160mm Borosilicate Glass Plate Bed Flat Polished Edge w/ Corners Cut
Amazon.com - 130mm X 160mm X 6mm (5.120"x6.30"x0.22") Borosilicate Heated Bed Glass Plate
3/32” / 0.0925“ / 2.35mm
Doesn't have to be this exact thickness.
6 beds - $5.68 ($0.95 each)
16” x 20“ x 3/32”
Lowes
Home Depot
4 beds - $3.98 ($1.00 each)
12“ x 16” x 3/32“
Lowes
Home Depot
4 beds - $3.38 ($0.85 each)
11” x 14“ x 3/32”
Home Depot
2 beds - $2.68 ($1.34 each)
10“ x 12” x 3/32“
Lowe's
Home Depot
1 bed - $1.98 ($1.98 each)
8” x 10“ x 3/32”
Home Depot
Note about Home Depot online listings:
Listings say thickness is 1/8“ or 0.125”, Reviews and personal purchase of in store product confirms it is 3/32“
A “Z-spacer” may be needed but not always.
See the dedicated Z Spacer Thingiverse collection page or take a look at few listed below.
Monoprice Select Mini Glass Bed Spacer
http://www.thingiverse.com/thing:1621650
MP Select Mini Z Spacer (customizable, no disassembly!)
http://www.thingiverse.com/thing:1808029
MP Select Mini Z Spacer (snappable)
https://www.thingiverse.com/thing:1958678
There are many ways to attach the glass to the bed to prevent it from moving while printing. See the Thingiverse collection below or on the dedicated Glass Bed Clips Thingiverse collection page.
Another option is Silicone Thermal Pad.
400mm x 205mm x 0.5mm Silicone Thermal Pad for CPU GPU Heatsink
Adding A Glass Bed - 3dprinterwiki.info
This is a pretty good guide on how to add a glass bed using silicone thermal pads. Is is meant for the Wanhao i3 and clones but should give you the idea.
Binder clips are an quick and easy way to clip the glass to the bed. You'll probably need to adjust the placement because the stock fan shroud can catch the binder clips in some locations.
