A Copernican View of the Turntable System

Brad,
There are unfortunately no free lunches?
A truly "universal arm-pod" like Corby's, requires many 'connections' and 'cantilevers' all held by grub-screws or something similar.
The vertical micrometer is in itself a cantilever from the fixed base and then the arm 'platform' is cantilevered from this shaft.
In any cantilever, the bending moment increases as the square of the cantilever. The deflections involved in such solutions render the stability of the arm-pod questionable.
I find with my DaVinci Grandezza 12" Ref tonearm, that even extending the shaft to its maximum for VTA adjustment, affects the sound rather badly :^(
Cheers
Henry

Dear Brad, The machinist in casu is alas not my friend, so
even just one lunch , not to mention the plural, is out of question. My 'luck' is that this guy is also interested in tonearms. However my armpod is made by my
real friend Vidmantas by the Reed company. I am also lucky
I should think that I am able to pay for the 'lunches' in plural. BTW there are 'many' other things involved by the tonearms so to 'have' a machinist is as important as to have an 'beautiful lady' ( not from Italy of course).

Regards,

brad, you are correct in the 3" dia and 3" height. it's solid stainless and it is heavy. you're also correct in the amount of thought required with the design. i spent lots of time at that stage before the machining started. all of my plans were on scraps of paper and napkins! the emachine drawing is a definite asset.
henry, your observation about the cantilevering is a correct one. the only issue that i have with that is my armboard. the vertical shaft is solid 1" stainless. i can understand the extension within the arm itself making a sonic difference, since it's really only a relatively thin-walled tube supporting the whole arm. mine is set down, bottoming out and i let the 1" shaft provide the height adjustments. the reason that my armboard is so long is that i wasn't sure how much clearance that i would need for the grandezza as it swings past the micrometer. it turns out that i have a good 1" plus clearance, so i will make a new armboard, shorter and thicker at the shaft end for more contact area. i am happy with it now and don't want to break the set-up, but i will in the very near future.
thanks for the comments. it's still a learning experience.
don

Don,
It seems as if you know well the pitfalls of 'structural gymnastics' and are learning more 'on the job'...so to speak :^)
I'm impressed and looking forward to further evolutions of your ingenious arm-pod.
Cheers
Henry

I am lucky in that the tonearms I was using when Henry’s thread came about were top mounted ones. This made design of my pod very easy and allowed for all the mass to be in the pod itself – no hollowing out required no extra parts - so to speak. It won’t win any design awards but its purpose is all functional and it is immovable. If you can tap holes for screws and spikes u can make this totally yourself.

All of the hinges, bolts and screws that I adjust for VTF, Azimuth, … are part of the tonearms themselves. This is just one solution and it has made life for me and this part of the hobby a simple and satisfying one.

My latest tonearm the DV-505 was selected because it looked very interesting yes, but it is also a top mount and looks like it was built by Dynavector for a Pod. Its very portable. Its perfect for it. I have been totally intrigued by its design and its ease of setup on both a pod and a plinthed TT using the Dynavector Jig.

Cheers Chris