"Richard" wrote in message
...

I think there is something to be said for 2. Might mean items are not
available off the shelf though.

Actually the only issue is the dipole center peice. Getting 3/16"and 5/16"
tubing is no big problem, (although a lot of stockists just have 3/8").

5/16" will fit with sleeving in a dipole center peice meant for 1/2"tube.

I bet I could substitute 5/16" with 3/8" for DE in the design with very
little efect.

That leaves me to mount 3/8" tube in a dipole center peice meant to take
1/2". Simple, sleeving should do.

And then you think, ah, just use 1/2" tubing for DE. Again that won't make
much difference.