Hello....I am making a vibrating table to polish marble.

Would appreciate input on the mechanism to make it vibrate.

So far.....steel pan....4' x 2' mounted on 4 heavy duty rubber isolation mounts.

Idea 1....4 foot long HORIZOTAL shaft in 4 pillow blocks...and 2 cam lobes running along the side of the pan....pushing it sideways.

Idea 2 VERTICAL shaft underneath with a cam lobe on the end....spinning around and hitting a metal bar, welded to the bottom of the pan...pushing it sideways

Idea 3 Vertical shaft underneath with a cam lob spinning around inside a ring....welded to the bottom of the pan....pushing out in 360 degrees....

Idea 4 should I do something with an eccentric? if so what?

Would appreciate any input...

Thanks, Leland

Hi Leland,

I've done this on a smaller scale. I needed a cheap, but larger than
normal vibratory bowl for polishing jewelry parts. I used a 18" pan for
changing your car oil and an $11.99 walmart fan motor.

The motor was mounted in a wooden ring with 4 springs around it.
Different thicknesses and lengths of springs were tried. the bowl
was attached to the top of the springs on a second wood ring...
cut out with a simple circle cutting router attachment.

I just bolted a piece of brass to the motor shaft to make it wobble
like an SOB....A few experiments with the springs(they're pretty heavy
duty...from ACE hardware) and it worked like an industrial charm.

I still have it. I ran it for DAYS at a time for about 12 years. I was
always prepared to upgrade the motor to a regular 1/2 horse or so,
because I was so reliant on the thing. But it just kept working.

I'll have to get you some pictures. It's a sorry looking thing, but it's
unstoppable. That on an adjusted scale would work great. I wanted
to do the same thing you're talking about to polish flat surfaces, but
I just haven't gotten to it yet. CNC got in the way ;)

John

Check this one out, a simple but very nice solution:
http://www.cnczone.com/forums/showpost.php?p=341777&postcount=2079

Regards,
Sven

Idea 3 sounds good with the 4 rubber mounts ,you may like to use a bearing on the end of that vertical cam to give it some life and reduce some friction.

I built a 48" x 96" vibrating table for casting concrete 10 years ago and still use it. Check out Vibco for electric or pnuematic vibrators, and you'll definitely want to use air bags to isolate the table from the base, unless you want the whole house shaking loose. I got mine from Goodyear. If you want more details let me know.

Burt