Vibraplane: Should it be loaded close to limit?


I just bought a Vibraplane 2210. It has a maximum load of 275 lbs. I plan to put my unsuspended SME Model 10 turntable on it, replacing my Townshend Seismic Sink. My question is this: Because my turntable only weights about 30 lbs, should I preload the Vibraplane to get the total load with my turntable closer to the maximum load? Will this improve the isolation? If so, what do you recommend I use to preload it? I was thinking a sheet of steel, aluminum or granite. Any advice would be greatly appreciated.
peterayer
Great feedback, guys! Richard and Peter, I'll be interested to hear your thoughts on auto load leveling and the lack thereof as you guys get more time with these units. I'm interested to know how well each unit holds pressure, and how often they need to be leveled in normal use. A passive would certainly be easier and cheaper to build.

These commercial air springs have stiffer side walls which give them an advantage over simple air bladders.

Richard, can you see a way to add a valve in the airline just before the Vibraplane? I assume there is a pressure gauge in the vibraplane. Closing that after pressurizing may tell you if the slow leak is in the unit or before. Does it bleed off air normally as part of the leveling? I'm not sure the compressor running every 6 hours or so would be enough to build up moisture in the air lines. That is the only reason I would even think about how often it cycles. I also wonder if it could be sufficient to run one off of an air bottle in a closed system.

Don't laugh at the bathroom scale trick. We used to do that with our race cars to set the suspension. One scale under each wheel. Obviously, these were pretty light cars.
Dan,

Indeed the Vibraplane uses a type of air spring which I think contributes significantly to its excellent horizontal isolation; they are not mere bladders, or else I'd just do the inner tube trick and be done. The compressor has a regulator and moisture trap, and the Vibraplane has its own regulator valve as well. Alas, I traced the leak back to the unit itself, and not the air line(s) on or from the compressor. While I am uncertain if it's actually an air spring leaking or one of the leveling regulators (for lack of a better term) it still means having to flip it over to find out - soapy water at the ready. There's also a lot of air tubing running all over the place under there, so it could be that as well.

Needless to say, I'm going to have to return to the sandbox for a while until I can pin down the problem. Of course cajoling friends into helping one heft these things around usually takes a free dinner and plenty of beer...ah the lengths we go to for this hobby.
I'll keep my fingers crossed the leak is at a connector. I can imagine there are quit a few of those.

FYI to anyone following along. There is a used 2212 on ebay, no compressor. It is too far from me for shipping so I didn't buy it.
Palasr, do get in touch with Solong - he too has some history with leaking Vibraplane tubing/ feet. I'm sure he can give some hints which might spare you part of search/repeated tries.
Good luck,
D.
The one on ebay looks ancient! I think $100 is optimistic for a shipping price, as you'd need to use a freight carrier.

Thanks Dertonarm, good to know. Cheers!

-Richard