Reddit reviews Seaboard High Density Polyethylene Sheet, Matte Finish, 1/2" Thick, 12" Length x 12" Width, Black
We found 2 Reddit comments about Seaboard High Density Polyethylene Sheet, Matte Finish, 1/2" Thick, 12" Length x 12" Width, Black. Here are the top ones, ranked by their Reddit score.
Excellent scratch resistanceGreat impact and stiffnessWeatherability (UV stabilized)Easy to machine with standard toolingRoHS compliant
Any cutting board made of high density polyethylene (HDPE) should do, or you could just get a large board like this in the size you want.
stuff like this - https://www.amazon.com/Seaboard-Density-Polyethylene-Finish-Length/dp/B00JPHTIES/ref=sxin_13_ac_d_rm?keywords=hdpe+sheet&pd_rd_i=B00JPHTIES&pd_rd_r=dd15ad70-7a36-4a2c-b07a-7f3801f9c4cb&pd_rd_w=csGJ0&pd_rd_wg=2UPvX&pf_rd_p=b3dd82c1-af3b-4cc4-a37f-5ce666fd2ce2&pf_rd_r=XXTYQRAAKD721AFJE4BD&qid=1559133144&s=gateway
https://www.amazon.com/PolyCarve-Density-Polyethylene-Finish-Length/dp/B00JPIB0C0/ref=sr_1_9?keywords=hdpe+sheet&qid=1559133144&s=gateway&sr=8-9
be warned that it can be REALLY slick.
I use the clamp, but I put a small square of plywood underneath and a small square of HDPE on the underside of the top of the clamp(the visible portion on my desktop) to spread the pressure and make it a little more sturdy. It also adds a nice little tapering effect.
I didn't want to drill through because I am not totally certain what the veeners are filled with in the spaces that don't have screw holes for the legs...