Building high-end 'tables cheap at Home Despot II

Mosin, Yes I remember quite well the details of the argument between the Welsh and the US slate plinth-makers. The photo of the slate roof going to seed was a real hoot for its irrelevance and scare tactic. And I agree, from an empirical reasoning, one would think that a soft slate might actually be superior for plinths, even assuming that Welsh and PA slate differ appreciably in that quality. Personally, I don't have a problem with the price of these products; one always has the option of not buying and of DIY.

What struck me about Hxt1's idea of putting slate over MDF/plywood is the similarity to Jean's recent brief mention of using acrylic on top of an MDF/plywood plinth. There is a lot known about the properties of matter that relate to absorption and reflection of transmitted energy between dissimilar materials. One needs to know the values of certain constants for each of these materials to figure out whether these expts have potential. OR build and listen.

Lew,

To give a bit of background, I'll take you back several years. My first e-mail to Jean expressed an interest in building a turntable from cement or machine grout. I abandoned that project shortly after, but the idea always stuck in my mind. Later, when slate hit the scene, I remembered the idea, and looked for similarities. There were many, and working with slate appeared at first glance to be easier. Shortly after that, I started my current project which makes heavy use of slate.

What I have learned, so far:

1) If you combine plinth materials, (I haven't) be sure to study which one should go where. I say this because slate is astonishingly effective, and it should be used in those areas that generate the most noise and vibration.

2) Building with slate isn't an easy road to travel. If your project is complex, there are so many issues to be aware of that it boggles the mind. Is it flat enough? What glue should be used? The list goes on. Also, using slate is a lot harder and slower to work than wood or acrylic. Still, it can be done with normal tools, unless you require extremely precise cutouts in your design.

3) Most mistakes are expensive ones. A small error can quickly take you past the point of no return, so be very methodical in your approach.

4) Slate is the most effective constrained layer material that I have ever used. I mounted a motor directly on the surface, and could not hear it with a Litman pediatric stethoscope from less than a centimeter away. It is very impressive in that regard, but not dead like lead.

5) Soft slate works great. If you happen to lightly chip it, it is easier to fix than some harder material.

6) It's pretty, too. ;)

Regards,
mosin

Hi Everyone,
Well it certainly seems like old times a'brewin here.
Mr. JStark wrote:
"I do apologize if some of you find it not on topic.
just sharing some ideas that worked for me. Not a Lenco project but some techniques will be implemented in that project as well."
No apologies needed at all on this. Your experiences in other facets of plinth building or other "Non-Lenco" areas are quite welcome.
Not far back in the posting, Jean and I were discussing the merits of servo-controlled Direct Drives. So go for it, by all means.

After reading a good bit about the slate upsurge here and elsewhere, I'm certainly rethinking my intended use of a doctored marble surround in a traditional Baltic ply/mdpb plinth. The reclaimed marble, which I have tons of, was going to get internal bore-outs with epoxy fills before fitment to a reduced size traditional plinth. However these heroics with unknown prospects in reducing marble's resonant ringing properties might not be worth the effort.

Maybe a good compromise in choosing a slate quarry would be something along a "Baltic" pedigree. :)

Oh Lew, I believe Jean's use of use of acrylic is not aboard any of his plinths, but is used in conjunction with marble as an "underfoot" base.

Sail on, guys!

- Mario

"Oh Lew, I believe Jean's use of use of acrylic is not aboard any of his plinths, but is used in conjunction with marble as an "underfoot" base."

Guys,

My last turntable used acrylic over wood, and it is quite effective.

mosin

Hi Mario,
good to hear from you. Always a pleasure.
Thanks for understanding. That was my point exactly.
We can all gain from each other experiences.
(I am sure my MMF-7 arm-board looks familiar. LOL)

My take on use of wood, MDF or ply. is that it is relatively easy to work with and effective. Its only drawback is that you need mass to get the most out of it ( For truly great design I would not go below 65 pounds). I sounds great on triple layered plinth too (I have tried that - experiment is more like it) but it leaves you only the after taste that won't go away. I am no builder or anyone that should be taken seriously in TT design or someone that has the know-how. I build TT for fun and my own satisfaction and use materials & techniques that make most sense and are within my reach and skills.
Using slate might be too time consuming and costly to make it right. Slate is difficult to work with and fragile. It can get complicated and fast if your design isn't anything but simple. I personally would not take upon myself to use it in my projects. I do however have access to a 'Soapstone' and guy who can and will turn my vision into reality. But how would that work in Lenco plinth design - sound wise is everybody's guess. But it might be something I may explore in the future.

Cheers and
happy listening

Mariusz