Hi Sean, that's display artifact under high zoom.

Numeric calculations that are done on the computer have a limited range of precision and when you zoom in quite a lot you'll see evidence of that limited precision, one of the ways it manifests is being able to see the little steps between representable numbers.

Are you possibly working with very small values like is the height of your object there some small number like 0.0001 units high? If so then you don't want to do that, you want to be working with numbers more in the range of like say 1000 to 0.1 , not some small fractional values because there will be more loss of precision with small values like that.

- Michael