Machine vibration reduction

[EvilKraut]

I'm building a 20 hp abrasive lab saw. The frame is 60" x 72", made from 4"x4"x1/4" walled tubing. A pivoting saw assembly sits on a webbed riser on one corner and weighs 590 pounds - as much as the frame. I have some vibration in the frame that I would like to minimize the old fashion way through mass. Hypothetically, I could fill the tubing with concrete (very messy but will add stiffness) and more than double the weight. However, would plain sand accomplish the same thing by absorbing the vibration? I have no vibration analyses. The spindle and motor are adequatly ballanced. I'm looking for some simple tips in reducing vibration.
Thanks for your time,
Frank

 

[btrueblood]

I like the idea of filling with sand or steel/lead shot; it would definitely absorb a lot of the vibration and noise. Machine turnings/chips would do as well, but wouldn't pack into the tubes as nicely.

 

[MachinaMan]

Hi EvilKraut,

Have you thought about using a dynamic absorber ? Figure out the natural frequency of the system and attach a mass/spring system of the same natural frequency (but a lot smaller) underneath your frame.

Hope this helps