On Jan 9, 9:32 pm, "Garland Gray II" wrote:
If I were to wax the outside of a piece of 2 1/2 inch pvc pipe about 6 feet
long, and then lay up several layers of fiberglass and epoxy, would the
resulting tube slide off the pvc easily enough after curing ? Or would I
need to first wrap the pipe with sheet plastic or similar ?
Thanks !

After the goo sets up, running a source of heat inside the pvc could
soften it enough to pull out, or even to melt it out. Epoxy wouldn't
be bothered by the heat required, I suspect.

Alternatively, perhaps a plug of wax wrapped in a seperator would more
easily be melted out. It's called the "lost wax" process.

Or, a spiral coiled cardboard tube could be pulled out after set up.

When I relined my rudder tube, I used epoxy with graphite shaped with
a pvc pipe pulled out before setup and sanded inside after set up
using a balloon and sand paper. I was worried that I might need to
cut a tooth in the rudder post and use it as a tool to bore out the
hole, or to use a hole saw and guide setup.

I am told the "proper" way was to install top and bottom rudder
bearings, but that would have cost quite a bit.

Seems to have worked out, no more jamming or juddering under moderate
loads.

Terry K