I’m looking to buy a surface plate, or other piece of very flat stone. 12" x 12" minimum. I think I’d prefer the 12" x 18"
Ordering online, the shipping is stupid expensive.
The only place locally I can even think to buy something like this is Production Tool Supply. I’ve never been there, and I’m not sure if they stock something like this anyhow.
A sink cutout from someone’s granite counter top install would work for me, I thought I’d check here before ordering with Production Tool Supply.
On another note, I think having a good surface plate at the maker space would also be a good idea. Using the table saw surface to check for flatness has it’s share of problems.
production tool does have a 12" x 18" surface plate for $47.55
I have a 1-1/2" x 3" x 13" granite plate that used to be part of a lasar measuring system in a machine, level to .0001" across the surface. that the space can have it they want it
Thanks.
I ordered the one from Production Tool, the price wasn’t too bad. They also have a 18" x 24" in stock for under a $100
cool, i left my 1-1/2 x 3 x 13 block at makerspace, they wanted it
Just out of curiosity, what are you needing a surface plate for?
For surface plating 
Actually, I’m going to assemble my Prusa MK3 at home and don’t really have a good flat surface to make sure the frame is straight. And after it’s assembled, I’m thinking about securing it to the plate so I can have a rock solid printer.
I’m sure I’ll find other uses as well.