Nude TT / Armpod question

Mine is not separate but is largely decoupled from the plinth by the use of a Pete Wriggle VTA adjustor. Arm is held on table by its own weight and not bolted on. See the Wriggle web site for pictures and more info. Seems to work well.

Depends on how strict you mean by "strict distance relationship between
the arm pivot and the spindle center?" I have a separate 15lb armpod
and I tested the theory that alleged movement. I aligned my cartridge
according to the Mint lp protractor, used the set up for x amount of time and
then put the Mint back on: no movement that I could see with that tool. If
someone wants to argue that with better tools I would be able to detect the
movement, then fine. But that's a moot point as far as I'm concerned. IMO, the
weight of the pod and the type of coupling feet (spikes in my case) one uses
should prevent any gross movements. I have a lighter 8lb pod that doesn't
appear to move either, but I never tested that one.

OK, thanks gents.

If one uses coupling/decoupling spikes on both the
motor assembly and the arm/cart assembly, and the
spikes go into something "soft",i.e., a piece of wood,
the SAME piece of wood, that is, then I can see that
the spindle-pivot distance can be maintained.

The question of both assemblies being vibrationally
isolated from each other, in this instance, is topic
for a different post.

My interest here is primarily how to maintain the
spindle-pivot distance (while observing motor-cart
isolation). Two big weights could possibly drift apart,
or the dog's tail could move one of them, etc.
Banquo, it's comforting to read that you've had
good luck with your setup.

For example, one could not place the two assemblies
in a box of sand, or on a big lump of clay even.

Possibly I'm making too much out of this issue.
I'm seriously considering such a project, and I want some
certainty the design will work once I start spending.