I have had a Grizzly grinder for a few months now and it really vibrates like mad. When I try to flat grind against the platen, as I begin to push against the belt the blade starts hopping and clattering against the platen. I have to apply a lot of pressure against the platen to minimize the vibration and the chattering of the blade against the platen. I thought it was the wheel so I ordered and just received a 10" wheel. The new wheel does not fix the problem, only seems to worsen it. Any suggestions on how to fix this problem?