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NavyChief
11-30-2007, 12:43 PM
Is there an unwritten standard for the amount of smaller tube that should be inside the bigger tube???

I am building a rocket (going to be a company rocket) but the bottom portion will be either a 3" or 2.66" BT with the top portion being either a 2" or 1.66" BT. Is there a "go-by" standard of how much of the smaller tube should be down inside that bigger tube sandwiched between CRs to keep that joint from being a weak link???

Wow, what a sentence!!! Must be the "friday" syndrome. :D

respectfully,
Anthony Jackman
SI International (OKC)
eLearning Application Developer

stefanj
11-30-2007, 01:09 PM
There's an unwritten standard, but we can't let you know because then it would be a written standard!


Um, seriously, it depends on the length of the upper tube. If the upper section is really long any lateral pressure will yield more force on the joint.

Off the cuff guesstimate for a good strong transition: About 6".

moonzero2
11-30-2007, 01:16 PM
Off the cuff guesstimate,....

Would be a non-written,...

Doug Sams
11-30-2007, 04:02 PM
Is there an unwritten standard for the amount of smaller tube that should be inside the bigger tube???This is close to the same question as how long a coupler should be. IMO, the upper tube should extend into the lower tube by 1 to 2 calibers of the lower tube - ie, about 3 to 6".

Also, the tighter the rings are, the shorter this length can be, assuming the rings are perfectly centered, which ain't always the case. That is, I can deal with loose rings much more easily than I can deal with offcenter ones :(

Doug

Intruder
11-30-2007, 04:03 PM
[FONT=Comic Sans MS]Is there an unwritten standard for the amount of smaller tube that should be inside the bigger tube???

I am building a rocket (going to be a company rocket) but the bottom portion will be either a 3" or 2.66" BT with the top portion being either a 2" or 1.66" BT. Is there a "go-by" standard of how much of the smaller tube should be down inside that bigger tube sandwiched between CRs to keep that joint from being a weak link???

Wow, what a sentence!!! Must be the "friday" syndrome. :D

I feel you on that one. "Schools, out, for, the weekend!" Oops. Did I type that? :eek: :D