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Tone Arm board material

My VPI Ares3 turntable which is made with a laminated acrylic/aluminum/acrylic plinth, about 2.5 inches thick in total, has a 5/8 inch circular cut through the top layer of acrylic which exposes the center laminate of aluminum.  Set into this circular cut out is the 'puck' arm board mounting disc which is about 7/8 inches thick acrylic.  This bolts to the aluminum via three machine bolts.  My SME Series IV magnesium tone arm is bolted to the acrylic tone arm puck.

Magnesium is known for its superior vibration and sound deadening qualities, so I was wondering if anyone has any thoughts on making the tone arm board 'puck' out of solid magnesium vs. the factory supplied acrylic??  I can see why they probably don't use magnesium as it's super expensive.  I just got a quote on a small piece of magnesium to machine a new tone arm board and its $125.  But if it were to make an improvement in performance, its cheap money.

Does anyone out there have any thoughts on this?

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whostolethebatmobile
290 posts
 
Delrin is also a good suggestion. It's already used for the body of new Hana ML phono cartridge, and the base of high-end isolating feet (Revopods).
bdp24's avatar
bdp24
9,397 posts
 
By the way, the generic name of Delrin is Acetal. There's also a long chemical name for it (abbreviated to POM), but you don't need that.
travbrow
272 posts
 
I’ve read that a plain old aluminum/MDF/aluminum “sandwich” has very good damping properties. I’ve made a Lenco based turnable plinth a few years ago from aluminum. It’s two layers of aluminum with a thin layer of damping material in between, I can’t remember the name of the damping material I used though it worked okay. I haven’t been using that Lenco build, but plan on redoing it with MDF as the middle layer. Also scrounging up cheap parts for a DIY tonearm. 
bdp24's avatar
bdp24
9,397 posts
 
@travbrow, is the damping material bright blue in color? If so, it may be EAR C-1002 Isodamp, considered the constrained layer damping standard in the industry (though Geoff Kait disapproves of it). Michael Percy Audio sells C-1002 in varying thicknesses. Another good cld material is Wall Damp by ASC (Acoustic Sciences Corp., makers of Tube Traps), sold in 4" X 4" pieces for a pittance.
travbrow
272 posts
 
The stuff I used was tan colored “plastic damping sheet” I bought from small parts years ago, which I think is no longer in business. The material was meant for damping of electronic chassis etc. 
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