kitestring wrote:Quick test in back yard to make sure mechanism works.... just at 30psi. Will be dropping non return valve and using simpler idea on next version. Merry Christmas and clear skies.
That looks great. Just a little curious why you are wanting to drop the non-return valve. Wouldn't that allow the two chamber to equalize and therefore no longer have a two stage rocket?
Probably missed something here, just checking.
-Blenderite
Check out my YouTube channel: https://www.youtube.com/c/Blenderite
Gday
Will launch with valve and do with tube capped and a small hole drilled
As it takes just a couple of seconds before second stage launches the pressure will hardly change as the water squeezes out of hole
J
kitestring wrote:Gday
Will launch with valve and do with tube capped and a small hole drilled
As it takes just a couple of seconds before second stage launches the pressure will hardly change as the water squeezes out of hole
J
Hey bugwubber, is that pressure sensitive or acceleration sensitive? I made one with the classic Clark CTL, but with a weighted collar. It would separate above 25G, and works perfectly.
Nothing can stop a curious mind from inventing- Anonymous
After a failure with a 2 stage rocket launch last month, I have modified the clamp system with extensions. The previous failures were caused by the sleeve (radial deploy system) distorting under pressure from the upper stage and allowing the clamp juts enough room to release. The plastic extension arms are designed to clamp to the upper stage which has a firm shape and cannot warp so easily and therefore should not allow prematurely release... Here's hoping.
Thanks Bugwubber.
Got it to work. Not very high but the mechanism worked fine. Sorry about crap vid but hard to do by oneself as well as launch. The second stage was wrecked and the drogue failed to deploy the main chute but will try this again sometime.
Thanks again for the idea. had a lots of fun building it. Mine is made from just ordinary ply with a bit of fibreglass (badly) applied. No metal fittings. Hinge rods are bamboo skewers. Max pressure they have been subjected to is just 85psi.
Aim is to add a second stage on top of a larger rocket with drop away boosters...
cheers
Here's a closeup of the orig. The amount of force pushing out on the shroud can be reduced by minimizing the distance from the pivot pins to the lever retaining notches .
IMG_20160214_104639.jpg (160.2 KiB) Viewed 30 times
Good point Bubwubber. Part of the reason mine is so far away is so i can pack a chute behind the shroud, but I will definitely have another rethink. Extend the mount tower higher for better mechanical advantage and still room for a chute. It did work though. Will fly again next month with a bit more pressure.
Couple of questions please.
I presume your design works on 90mm bottles? Have you built one for smaller 70mm? That's what i use for second staging and there's not a lot of room for the lever.
What did you build you levers from? Mine are just cheap ply with a tiny bit of fibreglass.
Has anyone else actually flown this idea? I have looked through the thread and can't find any sign of flight and recovery? US Water Rockets perhaps? The radial deploy is your idea.?
bugwubber wrote:So yes I flew it and the stage mechanism worked...but the upper stage disappeared. Multiple days and Hours of searching....nothing.
I did a second launch where my shroud got stuck so that came down in one piece.
Then I got busy and haven't launched since.
The levers are made out of plastic material.. PVC or ABS maybe?
1455718409636-310257806.jpg
I used pieces of a carbon fiber fishing pole for the pins.
Thank you!
That substrate looks much better than ply. It's a hobby full of things that can go wrong. Sometimes that's fun and sometimes it's not. Look forward to seeing your next try/project, cheers!
I just don't get why Bugwubber and Jeremy used two retainers instead of 3 or more. At least the stress would be cut a third (3 retainers) or even half (4 retainers). Anyway that's my call.
Nothing can stop a curious mind from inventing- Anonymous
Brian wrote:I am impressed by how simple this stager is, I want to build one now.
Are you building a new upper stage?
Yes have rebuilt upper stage. the tommy timer jammed and chute didnt deploy. Have changed to raketfuedrockets.com trigger and Star picket timer (I'll elaborate on when I get time) which allows finer timing. Will relaunch when i get the chance. It's a challenge and I'm sure it can be improved upon.
Hope to see more confirmation of the idea and improvements on this forum.
Please note Bugwubbers comments on mechanical advantage of pivot point. I built mine the way i did as i needed room for a parachute on a narrow second stage (70mm) see earlier posts.
All the best with build.
Alien Space Agency wrote:I just don't get why Bugwubber and Jeremy used two retainers instead of 3 or more. At least the stress would be cut a third (3 retainers) or even half (4 retainers). Anyway that's my call.