Advice for Building a turntable

Yes since it will not be a Spring Loaded design, Mass Loading will equal Mass Dampening. Make sure your rack is just as robust to handle this beast!

if you haven't already you should check out the forums on http://www.diyaudio.com/. There's one whole forum dedicated to Analog projects, and many DIY tables.

I see you have posted several questions in this vein here, and its not that this isn't a helpful crowd, but it is generally not a DIY crowd. I would follow the advice above and look for forums geared more towards DIY.