RE: DH 2
I use tubing a lot Paul. I have it for the axles on a 1/4 N28 (2piece swing axles) It weighs about 14 lb or so and they hold up well. I have 3/8" on the 1/3 scale N28 (38 1/2 lb dry) and so far so good. The id will accept 1/4 od tube or rod if there's a problem. I used it on a 1/4 SE 5a as a one piece axle and bent it on a bad landing, the Se is sort of portly at 23 1/2 lb and I wasnt too surprised when it bent, it was a crappy landing, no really it was.
Doc