Mirror Tiles and Glass for your 3D Printer Bed

This is an updated section.  While the glass down below works fine, and I used it forever, on my Tevo Tarantula.  With my Ender 3, I ended up buying a box of  6 mirror tiles at Lowes for $9.99 (12″x12″, and have them cut them down to size — ALSO: Make sure you get the NON beveled version).  This is a better price (though, you buy more) than the glass plates.  Ikea is also known for their mirror tiles, but I don’t know if they also cut them down to the size you need.  These work terrific, and I use hairspray.  Realize you may need to be a little closer than is normal with a PEI sheet to geta good hold.  When I level my bed on a non-mirror surface, I use a piece of paper and let it have a little drag from the hot end.  When using the mirror, I have a bit tighter drag on the nozzle.  

In my experience, these are not precision cuts.  There is a little gap or overhang after the cut.  Just be aware of that.  And, sand the edges down.  They will cut you badly, if you don’t.  

Custom Cut Glass from LowesGetting Glass for my bed

I let my printer run last night, printing some spinners (My daughter’s classmates love them).  When I woke up this morning, I pulled off two finger pads, and the glass came up with it, like it was part of the print.  This was really odd, but I had been planning on getting some more glass anyhow.  I ended up going to Lowes and found it for $2.68 per sheet (It comes out to 10″ x 12″ x 3/32″, or right around 3mm).  I then had them cut it to size.  

I like having multiple pieces.  I would say 2 minimum, 3 or even 4 being more optimum.  With 2, you can swap prints off while it is still hot, and let the glass cool off the printer.  The printer can print on the new sheet.  I have run into issues where I had a failure that I was able to reslice and continue from.  Having a glass plate that can come off and be put back on is nice.  

Previous to this, I was using glass from a frame I purchased cheaply at Walmart.  This custom cut glass ended up being a better price, plus fits better.  I wish I had realized this long ago.

Hairspray, for grip

On top of that, I am using Aqua Net Extra Super Hold – Unscented on the glass to help stick my prints to the glass.  For the most part, this works really well.  (and from the beginning of this post, you can see it can work WAY too well.  So, while it sucks that I had to replace the glass… (or, well, turn it over), it ended up being a blessing in disguise.  I can now pull a print off the bed, and leave it on glass to cool down, while I have another sheet of glass ready to go and print on.  

 After having used a smaller piece of glass for two months, I really wish I had realized how truly inexpensive buying glass at a local store could be, let alone one that is cut for my bed!