mtnmnstr

My Feedback: (2)

I have a scale project (Rocket powerd glider) With a wing span of 86 Inchs Lnth of 41 Inchs wing area of 774 inch It will be white styrofoam with balsa sheeting. My guess it will wiegh around 4 Lbs. Heres the question. What kind of reusable rocket motor can I use and where can i buy it?

Thanks
Gene

skerlock

ok lots of black powder and youll be able to use it as ...lets see... spare parts for the next one...

lol

scott

smokingcrater

The largest motor you can use without being certified by NAR (rocket AMA) is a G, although you can use as many of those as needed. ;-)

Check out http://www.aerotech-rocketry.com/cus...rpl_3-9-00.pdf
for more info, a G25W 120 N-s provides 8.4 peak pounds of thrust and 4.8 seconds of burn time. That isn't alot of extra thrust on takeoff, but decent burn time. Something like a quicker burning G (G125T) would probably leave a trail of balsa behind it.

You could also air-start cheaper and lighter motors if more kick is needed later. (estes D's come to mine) It would be fairly easy to have them eject themselves also to reduce weight after they burn.

Aerotech's are good, hard to get ahold of since their plant went up in smoke awhile back. (they were cutting propellant using a home made machine that used a regular shop vac from sears for dust collection. poor sparking motor + rocket propellant dust = BIG BOOM)

http://www.aerotech-rocketry.com/

Are you planning on launching using this or just an extra kick while flying? I would be worried about ripping parts off the plane! Rocket fins have a hard time staying on a high power rocket, I'm pretty sure big wings won't survive much better!

Balsageek

I know how to make a rocket engine. Its not resuable, but you could make your own. I used to do it in the boy scouts. You slowly (low temp) melt salt petre (potassium nitrate) and sugar together and pour it into a cardboard tube. (we resued estes tubes somtimes) It makes a pretty good propellant if you get the ratio right. (3-1 i think) Dont eat the salt peter though, or you will be wondering what happened to your libido!

ScaleArtillery

MetallicaJunkie

lets see it in action..... looks good

ScaleArtillery

Hi Their
Ican't wait neither but i had wanted to see what kind of input/comment i get befor i go ahead with a steel one I'm sure this one would melt unless i make a cermic insert. But i'm going to machine another one with smallr holes i just got my new endmills to make em smaller i think it will work great i have to make a jig to test te engine and pick up a dillon force gauge to get a good idea on the improvment of thrust with and with out the indctor holes in theory it should work like a torch. Also if this works good what would be a good pricefor them they take a few hours to machine. Let me know I love the way they look and i had always wanted to have one i think the b200 is the maxium leagle size someone said. I may try to make ne that use's jet fuel with glow plugs but the combustion chamber will have to be stronger you think. Also i may make a 2" dia one with a 3" nozzel that will look cool. Again thanks or looking and did you check out my cannons Austin

vicman

My Feedback: (10)

Try making the nozzle out of graphite