Tigerdude,
Why would your pushrod tubes be brittle?? I mount all of my pushrod tubes with epoxy and have never had a problem with it. If the tube mount is where it exits the fuselage I will mix corn starch (micro ballons) into the epoxy and then apply it to the tube/fuselage exit. This mixture helps to keep the epoxy from running and dripping out of place, and it also makes it easier to sand the epoxy smooth with the fuselage sides. As for other mounting holes inside of the fuselage I will use regular epoxy (nothing mixed in) to mount the tube with. One suggestion is to use a piece of sandpaper to rough up the outside of the tube so that the epoxy has something to "grip" to.

As for being brittle. Some pushrod tubes that are supplied with kits are made of a plastic that can be brittle and will splinter when you try to cut it. Here is a suggestion to help in that situation. Try to find a piece of dowel rod (or other soft material that you can cut) that will slip into the pushrod tube, the tighter the fit the better because you want this material to fit right against the walls of the pushrod tube. Push this material down to where you are going to make your cut, and then use a razor saw to cut the pushrod tube. Use smooth slow strokes to make the cut so you don't tear or rip the pushrod tubes. Give this method a try and you'll find that you'll get smooth clean cuts of the pushrod tubes.

Hope this helps.

Ken

Ken