I went to Home Depot and got a box of 12X12 mirrors, 6 to a package for $10...

same stuff I use.

Cut one down to size to fit my SD4 bed with a simple glass cutter ($2.00 item). held in place with binder clips and couldnt be happier! solved my warped bed issue - i can use nearly the whole bed now - and my prints are coming out much nicer since I can now properly level the bed, instead of trying to compensate for the warp.

...they have pieces that are used to join servo arms, or on quadcopters they use them as spacers to stack plates on top of each other. Anyways they easily thread onto the end of your printers stock Z axis adjuster screw, and give you the added length you need if you have a glass bed or longer hot end (or both)

Those things are called standoffs, and can also be found in various lengths/forms all over the net: m3 standoff

Also for people who have the S4 but want to retain the use of there adjustable Z Axis wheel (or any printer really) Ive found that if you just go to your local hobby shop that sells RC cars and Planes (or in my case Drones, which are basically RC planes or Quadcopters) they have pieces that are used to join servo arms, or on quadcopters they use them as spacers to stack plates on top of each other. Anyways they easily thread onto the end of your printers stock Z axis adjuster screw, and give you the added length you need if you have a glass bed or longer hot end (or both)

One more think Ive found. Those binder clips usually get hung up on the arms that you use to open them up and attach them. But once youve got them clipped onto the glass (I use the corners) the arms com off by just squeezing the part of the arms that goes into the clip together. Once you do that It makes it much more unlikely your print head will catch on it.

Also for people who have the S4 but want to retain the use of there adjustable Z Axis wheel (or any printer really) Ive found that if you just go to your local hobby shop that sells RC cars and Planes (or in my case Drones, which are basically RC planes or Quadcopters) they have pieces that are used to join servo arms, or on quadcopters they use them as spacers to stack plates on top of each other. Anyways they easily thread onto the end of your printers stock Z axis adjuster screw, and give you the added length you need if you have a glass bed or longer hot end (or both)

One more think Ive found. Those binder clips usually get hung up on the arms that you use to open them up and attach them. But once youve got them clipped onto the glass (I use the corners) the arms com off by just squeezing the part of the arms that goes into the clip together. Once you do that It makes it much more unlikely your print head will catch on it.

Keeping on my "all things Ikea" thought process (that place has had so much of my money) I use these mirrors http://www.ikea.com/gb/en/catalog/products/60074007/ on my SD2 which are a little big but it fits fine and the extra size also helps prevent run out as the nozzle heats up before printing. They should be perfect size for SD3+ owners.
Personally I still use kapton on the mirror but each to their own on that one.

I have seen it on amazon and through vendors that sell printer parts kits and supplies.
McMaster Carr sells 1/4 in borosilicate glass plate with ground edges for about $25 for an 8 x 8 and $14 for 6 x 6 . $2 for a can of Aqanet hair spray and $1.50 for a box of binder clips and you are in business. Currently just using window glass from the local hardware store. One caution I will add about the binder clips I used one on each corner in the front and a third  in the rear to the left of the leveling screw.  since the machine max X,Y,Z or home position  is at the back right corner with the nozzle almost touching the bed do not put a clip here  the tip will likely crash against the clip.  three is sufficient.
Tin

It might be worth doing if you want a matte surface for the bottom of your print rather than glossy.

Right, like a mold interior... thanks.

So if you happen to have some, why not use it, but I wouldn't make a special trip or arrange to have it made..

Hi all,

I was wondering if a finely sandblasted glass sheet has ever been tried? I'm thinking about tring that instead of plain glass and hairspay...

Some people use high grit sand paper and claim to have near perfect results with adhesion since the first layer and actually grip.
Sandblasting in specific? I never operated one, so I couldn't say...

I was wondering if a finely sandblasted glass sheet has ever been tried? I'm thinking about tring that instead of plain glass and hairspay...