I am installing a new cooktop in my corian countertop and I am about 1/2 inches to short on the width and length. What is the best way to do this? Will a sander work?

A sander will take forever and fill the house with dust. You can use a circulating saw, 4-5" preferable, with a carbide blade. You can also drill a series of holes at thee opening you need and then cut with a saber saw with a grit carbide blade and then finish sand. I will assume the cut edge is not visible.

dcounty

Check out this thread. All of the information is there.

https://www.askmehelpdesk.com/interior-home-improvement/how-do-cut-already-installed-corian-without-removing-603935.html

Ken