wrote:
Hey, I have a 90 degree pipe for a toilet flange sticking out of the
concrete about 1 1/2 inches.
So I bought a PVC, cast iron replacement flange. the one with the
compression ring around it.
I then cut the pipe level with the floor, but since it was a 90 degree
elbow, it didn't go straight down,but curved. So then I bought a bunch,
maybe 3 different flanges to see if any would go in. One of them went in
but obvious it wasn't tight to the outside of the pipe. Then I went and
bought a 45 and 90 degree pipe to see which one would fit in the existing
4" pipe the best. Neither did but cutting off the top 1 1/2 inch, it will
fit in the pipe with about 3/16 inch space around it.
The question then is: Would it be better to put silicone caulk in the
space to hold the pipe in place or an epoxy? Then the flange can get PVC
glued in to it. I hope the question is clear.
Thanks!
D

You said: "So I bought a PVC, cast iron replacement flange"

I'm confused. Is the existing pipe that comes out of the floor cast iron or
PVC?

If the existing pipe is cast, a PVC flange can be leaded in. I think that
would be better than either caulk or epoxy. You might consider calling a
plumber that has the skills to lead the PVC fittings to the cast to ensure
a firm connection.