You can cut aluminum tubing in a small miter box (I have an X-Acto unit), After cutting, use a small, fine file on the cut portion, then carfully run the file over the edge to remove burrs. Finally, take your Z-Acto knife and clean out the inside of the tube. Works for me every time.
I have a Deora screaming to be built. When I do it won't have the slant 6. I think I have a slant 6 in my parts bin too.