i'm suprised a hack saw wouldn't work if you kept it straight
I'm sure a hacksaw will do the job too; it just might try to wonder a little bit. If you take it slow though it shouldn't be bad. Plus, as long as it is cut just a little shorter than your total width, you should have enough wiggle room if the tube isn't cut exactly perpendicular.
For the 3W80Xi, I've heard that the Vess 26" prop is a nice match. I picked up a 26A and hope to try it within the next week or two. May try a 26B also. The Vess I got was balanced perfectly, tips and hub, right out of the package.
Dan