Alternative platters ?

[Qwin]

My drive/platter combination will fit a standard Techie plinth, but only after serious modification. It requires a hole in the casting where the bearing mounts, an increase in PCB pillars from 9 to 15mm tall and the creation of a filler piece for the gap around the platter as it measures only 300mm diameter, which is smaller than the Technics. Its easier and preferable to make one from scratch, so I will be producing a new plinth for this combination, but not till the New Year.

My priority is to finish my Girlfriends Techie with modified (carbon) straight arm as her xmas present.

My choice of material for my plinth would be slate, but I don’t have the equipment to work it and to have a custom one made would be very expensive.

I considered birch ply - its easy to work with and is popular for speaker cabinets, but the design criteria is a little different for a plinth.

I considered laying up some laminate myself. If you use thin layers of ply, 6mm or less and glue them with contact adhesive, this creates a flexible boundary between layers. By the time you get to 80/100mm thick you have a material that acts just like the commercial “Rubber Wood” which is made in a similar way. Not to be confused with wood from a rubber tree. It has very good acoustic properties in that it acts as an acoustic barrier transmitting virtually nothing from say motor or bearing to arm.

Then there is my long time favourite – Concrete
I will not use the Techie plinth as part of the construction this time, I'll use a mould to produce one from just concrete.

I read recently where someone used cat litter in the concrete mix, it was some type that was a bit like Pumice Stone. I have seen Pumice used under the feet of components as an isolator. It was reported to reduce the weight and make the mixture more inert when set?
Also heard of rubber granules being added to concrete for the same reason, so a bit of experimentation may be in order.

I will be using my Terminator Linear tracking Arm on the deck. I have been in correspondence with Vic at Trans-Fi Audio and made a few recommendations for very minor changes to the arm, which he has adopted, in particular a change to the mounting bracket which he is trying on a small batch. I have my name down for one when they are ready and can’t detail the arm mounting method on my plinth till I get this, so another reason why I will be delaying its start.

Anyway this is getting off topic.
I've proved the Platter works and I will certainly start a thread for this build when it’s under way.