On Sun, 13 Sep 2009 17:42:30 -0400, aemeijers
wrote:

HeyBub wrote:
I have a 5x8', pretty thick, plywood base resting on the edges three (maybe
four) 2x12 frames. This plywood base has on it a significant load, maybe 200
pounds. I would like to be able to slide the base (and the load) along the
support frames - not far, maybe two feet, do my business, then slide the

I have the same questions Aem has, plus if you do your business and
then slide it back, it will really smell bad pretty soon, and may rot
the flooor.

Unable to parse your sentences to figure out what you are talking about.
Can you post a link to a picture? Is this a one-time move or a recurring
thing? First thing that comes to mind is a couple stanley wonderbars and
some pieces of pipe. Second thing is four strong guys and carry it,
adding handles if needed. Third thing would be a couple of the lifting
furniture dolleys (like they move loaded desks with) mounted permanently
underneath, with a way to stick the lever in to raise them as needed.
There is not going to be a painless way to do this, and if there is
going to be a recurring need to move the thing, may as well go through
the pain once to do it right.