Thinning blades KMG flat platen

Nov 16, 2005
When I am thinning blades on my KMG flat platen blade's handle parts comes out not as flat and parallel as I want. I was using a graphite tape over pyroceram plate. I am going to remove tape as someone on this group suggested.
Is there any other tips to keep both blade's sides flat and parallel?

Someone on knfenetworks also recommended this device

What do you think?