I made a telescope tube for my 12.5 inch mirror (tube id ~364 mm), for my 8 inch mirror (tube id ~261 mm). and for my 6 inch mirror (tube id ~200 mm).  To make the tubes I needed to “roll” carbon fiber around a cylindrical form.  After the epoxy used to coat the carbon fiber set, I needed to be able to remove the inside form.  I used concrete tube forms from HD Supply.  These were thick-walled tubes – thicker than I could find for Sonotubes.  I built a roller system so I could spin the tube as I layered on the carbon fiber.  Before laying on the carbon fiber I waxed the tube with release wax and then put on a layer of release fabric.  I then started to layer on the carbon fiber – “painting” on epoxy as I went.  For the tube for my 12.5 inch mirror I used 6 layers of carbon fiber (6K 2X2 Twill and AdTech epoxy from Soller Composites).  For the tube for my 8 inch mirror I used 4 layers.  For my 6 inch mirror I used 6 layers which were then covered by a 6K carbon fiber sleeve.  After getting the layers applied I wrapped the whole thing with heat shrink tape (Dunstone, Inc. www.shrinktape.com, #220R 0.002” x 2.5”, release coated).  Or, in the case of the tube for the 6 inch mirror, I covered the tube with a heat shrink plastic tube.  I then used a heatgun to shrink the tape/tube and compress the carbon fiber layers.  After about 24 hr I removed the shrink tape/tube.  I thought I had a method (which I won’t even mention here) to easily remove the inside concrete tube but it didn’t work.  I tried another different method on the 8 inch tube when I made it, but that didn’t work either .  So I ended up ripping the concrete tube forms out, piece by piece.  That took hours to do – what a pain.  But at least the carbon fiber tubes were free of the inside concrete form tubes.  The carbon fiber layered up this way does not compress as much as those put under pressure in my marquetry veneer press.  I am sure there is more epoxy that doesn’t get squished out so the tubes are a bit heavier than I wanted but structurally they are very rigid.  Possibly, using perforated heatshrink tape might have helped – mine was not perforated.  However, Dunstone does carry perforated heatshrink tape.  The thickness of the larger diameter tube ended up about 3 mm.  It is ~370 mm in diameter (outside), 49 5/8 inches long and weighs about 12.5 lbs.  The thickness of the tube for the 8 inch mirror ended up about 2.5 mm. It has an outside diameter of ~266 mm and is 72 15/16 inches long.  I forgot to weigh it before putting in the optics – I would guess that the tube weighs about 10 lbs.  The thickness of the tube for the 6 inch mirror is about 4 mm and 30 inches long.  Below is an edited (shortened) video (no audio) of me making the tube for my 12.5 inch mirror.