Tim Wescott wrote:

Your "venetian blind rods" turned into "polycarbonate tube".

McMaster sells polycarbonate tube -- they have some 1/8 wall 5/8 OD tube
that should be OK, if a bit more brittle than I'd really like. They want
less than $2.50 a foot, and I should be able to get it for much less
elsewhere if I dig. I'll see what else they have.

You can get 5/8" hardwood dowels for
less than $.50/foot.

http://www.hobbylinc.com/htm/mid/mid7910.htm