Posted: Fri Jan 19, 2007 3:47 am
I didn't really explore their formula(s), just the calculator on the site. Pretty neat! Ben has tried to come up with a way to calculate the ideal length before, but it became too complicated too quickly. What we do know is that longer is nearly always better, as the lengths are generally past the limits of pneumatic launchers*. But that's why I recommend a much smaller PC and a longer barrel, for less pumping--but I have yet to build something.
Yup, nested pumps help, but you don't want too many. That would add excessive complexity, especially if a certain stage is already only a few inches long. Try going for a smaller PC/less pressure.
*On a sidenote, if anybody here watches Mythbusters, you might have seen their system to generate winds to send a reed through a palm tree. Not exactly a launcher, but really long, and nobody else is insane enough or rich enough to build one.
Yup, nested pumps help, but you don't want too many. That would add excessive complexity, especially if a certain stage is already only a few inches long. Try going for a smaller PC/less pressure.
*On a sidenote, if anybody here watches Mythbusters, you might have seen their system to generate winds to send a reed through a palm tree. Not exactly a launcher, but really long, and nobody else is insane enough or rich enough to build one.