Anybody up for it?

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Was wondering if anyone wants to donate some rocket motors to kick this
thing up to about 30 mph.
Even if you don't want to donate, would you have any recommendations for the
size of motors? I'm pretty light weight at about 135 lbs. The trike itself
weights about 60 lbs.
I wouldn't want to go much faster than 30 mph at first because this thing
can flip pretty easily. However, as I get use to handling that speed, I
could possibly graduate to higher speeds on a straight-away.
Reply to
Piccolo Pete
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rocsim it to see what kind of stabilizing fins ya need.
my first thought is an H90, encased in a cato-proof motor mount
Reply to
Tater Schuld
The rocket motors normally used by the folks on this group cannot be throttled or shut down once they are started. At nearly 200 lbs.I would think that it would take a fairly large motor to move the trike and you at 30 mph. I would suggest a Hybrid motor, one that runs on liquid Nitrous Oxide for the oxidizer and another substance to burn and produce the "hot expanding gas" for the thrust. A hybrid motor could be modified to allow the nitrous to be shut off effectively shutting down the motor. In theory you could re light the motor at a later time though I have no knowledge of how this could be done. Do a Google search on hybrid rocket motors to see what is out there. An alternative would be a Hydrogen Peroxide rocket motor but the fuel is extremely dangerous at the concentrations you would need. Check out
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for some ideas.
Reply to
Bill Richardson
Been there, Done that... with a regular bicycle when I was 12. I would suggest using a regular bycycle though as the thing you want to ride is marginally stable and would tip over easily. Another thing... if you use rocket motors don't ignite them when you are still, as they will probably push you over and not foreward. Be going a few miles an hour when you hit the button. Also be aware, like the other guy stated, once lit you can't turn them off if something goes wrong. On the bicycle, we used 5 SSRS F67 motors and lit them one at a time. They worked pretty good and they definately accelerated the bicycle, but I doubt we got to 30 mph, probably 20-22 mph. Looking back, we did some pretty stupid things! What's the saying... A little knowledge is a dangerous thing. Anyway, hybrids are the way to go but they cost a lot to set up and opperate correctly, so I'd suggest AP motors with an average thrust of 125-175 newtons and that last for no more that 1-1.5 seconds of burn time to start off with. These would seem manageable. And... BUY YOUR OWN DAMN MOTORS! Mad scientist types should be funding their own experiments and not bumming stuff off of other people! What's wrong with poeple from Florida! :) Daniel
Piccolo Pete wrote:
Reply to
DanF
I see top posting is common in this group, so I trust I won't get slammed for doing it...
I don't think it would actually take 200 lbs worth of thrust to push a wheeled vehicle that fast - after all, it isn't lifting it.
However, I am noting your comments on a hybrid motor. I have looked into pulse jets, but they appear to be too bulky for this use. As for Nitrous Oxide, that is also kind of bulky, but I suppose I could use a smaller tank than what I normally see in cars. My neighbors often install nitrous kits in cars for the local track, so I could get some help there.
Um... doesn't Hydrogen Peroxide use Hydrazoline? Or some kind of heavy duty acid?
I have a couple of thoughts on this. One is, it wouldn't have to start from a dead standstill. I could pedal it up a bit and kick in the burners. Another would be to use a number of motors that I could ignite individually - instead of taking the risk of getting up to undesirable speeds in early testing.
I have only worked with bp endburners so far (sky rockets) but have not attempted to put them on the trike. The largest I've ever made would probably be considered a 3 pound rocket. But I believe I have the equipment to make them a little larger, reliable, and safe. I don't like core burners because they tend to blow out my nozzles on ignition (but that just means I need to improve my tooling and materials).
Anyway, thanks for your input. I'll look into your recommendations.
Reply to
Piccolo Pete
I would definately start pedalling before lighting them and I agree, with solid fuel, I would want several motors to light in pairs (to keep some sort of balance and avoid a rapid steering problem). But you aren't gonna talk me out of using the trike if I ever do this :-)
Max speed I've had the trike was 25 mph - but that's about as fast as I ever want to go on a sidewalk. This would eventually be run on a nice smooth track - just for special occasions - and I would hope to eventually exceed 30 mph (wearing protective gear, of course). Fortunately, even though the trike can flip easily, it isn't a far distance to the ground and most of what I would be subject to would be scrapes/road burns unless an explosion takes place (which is why I'm not really looking forward to using liquid fuels).
I was thinking, um, after all, I do have brakes... Even though I may have to replace them after every run.
I'll look into the AP motors you suggest. I may just start with some hand made bp motors to get a feel for it. 2 six pound rockets with a 20 foot flame would look pretty cool on this thing.
As for your comment about Floridians... our brains get melted every summer - what do you expect ;-)
Besides, pride is cheap and it doesn't cost anything to ask :-) You never know when someone might be willing to sponsor an event. I know a guy that travels all over a few countries and makes $10k per show for riding a horse cart full of pyrotechnics around a track a few times. It costs a lot for the airfare, permits, and supplies, but he still makes a nice profit. So... why shouldn't I try to get into some kind of profit thing with a trike that already draws a lot of attention every day I ride it to the store to get some beer? Hell... I should probably sell advertizing space on the thing :-)
Aerotech... are you out there?
Reply to
Piccolo Pete
A bunch snipped, and comments inline...
LOL! I have seen people take falls from well over 10 feet, and come out unscathed. I have seen one person merely fall over... that is... tip over on his bicycle, and his brain hemorraged and killed him. I myself fell through the middle of 2 flights of stairs to the concrete patio below at 3 years old... I bounced... and I only have this little irritating twitch... .
Rule: Height of fall does not always determine life or death... but quite often determines quality of life. Opinion: I think everyone has a "time to go", with mistakes and sheer miracles determining quality of life, so I am not really against your stunt.
No you don't... not above thirty or so miles an hour... pedal-cycle brakes go liquid right around the same speed that cars hydroplane... that is uless you have more sophisticated braking on this thing... similar to motor-cycles... disks and such. The quality of single-disk brakes varies from design to manufacturer, but even those go liquid between 90 and 200 MPH. That is why larger aircraft have multi-disk and/or liquid-cooled brake assemblies. Mud-gravel pie (or tooth and brick... your preference) is not the time to learn the limits of your braking system. It's all about the friction.
Sell, sell, sell... there is always a buyer... but then again, sometimes it is quicker to come up with the cash yourself.
Cheers!
~ Duane Phillips.
Reply to
Duane Phillips
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caught this on tv a couple years ago. groups of hobby motors seem like a good way to do it. also, a set of motorcycle leathers would be a sound investment.
shameless plug... I've got a set of leathers on ebay now that i'm selling for a friend. (sounds like they might fit you) auction ends in 2 days and current bid is only $33. just do a search for spartan leathers, you'll find them.
-Dan Chandler
Reply to
Dan Chandler
Those are some old school leathers. Not too many people would trust them, as years of sweat turns the leather into beef jerky and they become less effective. Even without a lot of use the leather experts recommend replacement about every 10 years.
For 30 bucks they would be ok for a 30mph bicycle ride, but no way would I go race in them.
Reply to
Tweak

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