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TW Raven Owners: Set Up Questions

Through the magic of sweet talk, I turned my Orbe into a Raven and mounted my Graham 2.2/Benz LP.
I am looking for a isolation base for the Raven. I have a 1 3/8" piece of granite coming soon so I can ditch the MDF I use now (a temp. meas.!) Symposium, SRA, HRS, etc., can anyone share their experiences with isolation bases? I saw the thread about loosening the Stillpoints.
Initially I had an issue with using the rough side of belt. The belt shimmied up/down on the pulley at a specific spot on belt. Also, the speed fluctuated and I could never get it dialed in with the PSU. So, I went to the smooth side of the belt and then raising the back side of the motor (unscrewing one of the isolation feet) slightly moving the belt down from "center" on the pulley. This moved me from 33.2 to 33.3 and I have no more belt shimmying and the speed is rock solid.
I'd appreciate any tips/tricks etc.
gerardff
halcro's avatar
halcro
2,664 posts
 
30cm is quite thick for a concrete slab.....especially a prestressed one. How do you know this fact?
The load carrying capacity of any floor has little to do with with it's BEHAVIOR under dead loads, live loads and impact loads. 400 Kg/m2 is not so great considering that 4 hefty men each weighing 100Kg can stand on a floor area not much more than this?
A trampoline can certainly support this load also but I would be loathe to locate my turntable on one?
suteetat
435 posts
 
I checked with my building engineer who has the building construction
blueprint and that's what he told me, regarding 30cm thickness. I don't
really know building specification and don't know what is considered norm
and standard of high rise elsewhere but overhere 400 kg/m2 is the
standard as far as I know.

Also my next door neighbor bought a unit below him and managed to find a
small space to drill a hole for a staircase between the 2 units who also
mentioned that 30cm thick concrete was what he needed to go through as
well.
suteetat
435 posts
 
I just have a lead on Minus-K locally but it probably will be closer to the end of the year before I could try one (just in time for Chrismas, I suppose!). I wonder if something like Minus-K or Vibraplane is good only for non suspended table or also equally good for suspended table like Linn?
halcro's avatar
halcro
2,664 posts
 
From all reports.....a Minus K is good for all turntables.
peterayer
1,382 posts
 
I used my Vibraplane on the unsuspended SME Model 10 and noticed a significant improvement. I now have it under my suspended SME Model 30/12. I would say the improvement is only very slight as the 30/12 already has a superior suspension and I don't think that the Vibraplane offers much additional isolation.

I have also heard the Vibraplane under unsuspended Brinkman turntables and the sound was extremely good, though I can not say what actually contributed to what in those unfamiliar systems. I did hear though that that Brinkman dealer sells a lot of Vibraplanes for his tables.
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