Phil wrote:
I'm looking for a support to locate and hold a PVC sleeve in the center
of a Sonotube while pouring concrete around it.

Perhaps two plastic rings, one that fits inside the Sonotube and one
that fits around the sleeve, connected by radial members separated by
120 degrees would do the job.

Has anyone encountered a device that accomplishes the objective? I need
about 100 of these.

We always use tie wire through holes in the sonotube to hold
these types of things in place. Drill some 1/8" holes in the
sonotube on opposing sides and slip a double strand of wire
through the holes and around the pvc and out the holes on the
opposite side. Twist the wire from both sides, pull one side or
the other to align, and you are done.

We had a situation once where we staked the bottom of the pvc in
place using rebar driven into the ground and tie wired the pvc to
that. Then we slipped a piece of galvanized pipe down into the
pvc and placed a 2x4 (with an appropriate sized hole drilled in
it) over the top of the pvc/hard pipe and secured it in place to
hold the pipe centered. Held the entire run perfectly straight.

Unless you are doing something special, it doesn't really need to
be centered perfectly all the way down, just at the top and
bottom (and not really at the bottom, but that makes it easier to
keep plumb).

--
Robert Allison
Rimshot, Inc.
Georgetown, TX