KNO3/Sugar rockets!!!

[poisonkiller]

I made a KNO3/NaNO3 and sugar mix in a coffee grinder (a very-very little amount) and put it in a aluminum foil (I wrapped up one side). Then I pushed it with pencil and added a drop of water, so it stuck to the tube. Then I took some string and soaked in a water/KNO3/NaNO3 mixture and pushed it into the powder. When I lit the fuse, it didn't burn very well. At last, when I lit the rocket, it burnt away like smoke bomb. What did I do wrong?

[teknix]

"added a drop of water"

 

That is what you did wrong (assuming everything else in the design of the rocket works). The NaNO3 in the mix is VERY hygroscopic to begin with and adding water doesn't help. NaNO3 is a pain in the ass to keep dry and if your mix isn't dry it isn't going to burn very well. I would stick to just KNO3 as an oxidizer and try to keep it as dry as possible.

[pa_pyro]

I made a KNO3/NaNO3 and sugar mix in a coffee grinder (a very-very little amount) and put it in a aluminum foil (I wrapped up one side). Then I pushed it with pencil and added a drop of water, so it stuck to the tube. Then I took some string and soaked in a water/KNO3/NaNO3 mixture and pushed it into the powder. When I lit the fuse, it didn't burn very well. At last, when I lit the rocket, it burnt away like smoke bomb. What did I do wrong?

 

First of all, smoke mix just wrapped in an aluminum foil tube will not work like a rocket.(I figured this out about 2 years ago when I was just starting with pyrotechnics ) when wrapped thickly for small smoke devices. And did you mean you tried to light the fuse while it was wet, or did you wait for the string to dry after dipping it into the mix? Try making your rockets with smoke mix rammed into a paper tube, cored, with a clay nozzle.

[poisonkiller]

I soaked this string into water/KNO3/NaNO3 and waited it to dry. It was quite dry after 1h or 2. Actually, I found out, that this fuse sucks. First, it burns with a little flame so wind could put out the fuse, second, when it reached the point, where fuse was touching aluminum foil, it extuinguished, and third, I made a little mistake, what I forgot to post, it wasn't only water/KNO3/NaNO3 mix, but I add 100% water, 50% KNO3/NaNO3 and 50% sugar. How can I make a good fuse?

[Ozzy]

These are very fun indeed. I made some last night just messing around with my new KNO3, I tried packing it in a tube *dry* its scooted across the ground for about a foot and that was it. Then i melted some put it in the tube put nozzle (1/8 inch) placed it on the ground, i expected it to just fly across the ground IT DID for a few seconds then WAM it took off. I giggled like a little school girl i never new you could make actual engines with this stuff so tomorrow i will attach some sticks and see what happens.

[pa_pyro]

If properly made and cored this stuff makes pretty powerful rockets. Ever heard of R-candy? Poison, you should keep the smoke mix as dry as possible if it is made with NaNO3. If you nead a fairly reliable fuse make a trail of powdered smoke mix down a piece of tape, fold the tape in half carefully not to spill the powder, then roll the tape into a tube. For rockets like you are making that will have small nozzles, use thin masking tape or something similar. Sine you said earlier that you have acess to sulfure but not charcoal, and you have an oxidizer,(hygroscopic but it will work) then you should make BP. you can make your own charcoal by filling a tin with pieces of hardwood.(willow and alder seem to work best) Make sure to punch small holes in the tin to allow the gasses to vent.

[Ozzy]

So you guys melt the KNO3/sucrose putt it in tube press/ram and drill it out?

[poisonkiller]

No, I powder it in coffee grinder and then press into tube.

[Ozzy]

You think i should add any water or anything when pressing it dry to compact it better?

[styropyro]

Don't add any water to your mix, the compression from pressing/ramming with pack it good enough. The water would never dry with that tight of a nozzle so just ram it dry.

[poisonkiller]

I made another rocket today, at least I tried to... Here is the picturehttp://img53.imageshack.us/img53/8008/sugarrocketax9.th.jpg. It burnt away like ordinary smoke bomb. I can't understand what I did wrong. I made a paper tube, added a little tape to hold it together and for strenght, pressed the powder into the tube and put a aluminum foil nozzle to hold it inside. Damn it, it makes me crazy!

[oriansbelt]

hhmmm, nothing about that sounds right. Normally tubes are glued not taped, when the glue hardens it makes the tube much stronger than just paper and tape. Second the powder your using might still have some bugs in it(like moisture), and how in the heck is an aluminium foil nozzle suppozed to work? I don't understand what the "fuse made of match heads" quite means in the picture and I can't figure out what the picture is trying to tell me anyway. Please explain these things more so we can give you more help.

[poisonkiller]

Fuse of matchheads is basically a little tape and matchheads. I took some tape, put matchheads on it and folded tightly. I really don't know why the rockets need nozzles, so I think, that it is for making pressure inside and letting it out, so the rocket will fly. Also, I put aluminum foil in, so the mixture could not fall out.

[Ozzy]

Are you using GOOD KNO3?

 

EDIT: WTF Al foil for a nozzle?

[poisonkiller]

It's KNO3/NaNO3 mix! And I have no idea why a rocket needs a nozzle, so I put something inside, what could make a little pressure...

[pa_pyro]

You need to use clay(cat litter) or something that will not erode or melt for a nozzle. Al foil will just melt. If I can I'll find a diagram of how arocket should look. For fuse do the same thing you are doing with KNO3/NaNO3 and sugar except use the powder in place of the matcheads.

[poisonkiller]

Id love to see a diagram about rocket! At first I tried to light a fuse made of this powder, but its kinda hard to light, but when its burning, its a good fuse.

[pa_pyro]

http://home.alphalink.com.au/~brucej/nickle.htm This gives the general idea of how they should look/be made. Instead of having a coring mandrel and cored rammer you could use a drill bit to drill a hole in the nozzle and core the rockets.

[poisonkiller]

Hmmm... So I can use my method, but I have to make nozzle of clay. So when I light it up, the fuse will burn away, propellant will fire up and pressure will release through the little fuse hole in the nozzle and the rocket will fly?

[oriansbelt]

If you mean by "your method" just pressing the propellent in the tube then drilling the nozzle hole, then yes. The clay nozzle has to be rammed with a hammer first so it is really hard though, it can't just be pressed.

 

btw, the entire principle behind rockets is the nozzle i.e. the hot gasses being pushed out the nozzle to speed them up. Only very small rockets(like bottle rockets) can get away with not having a nozzle because they are so light.

[poisonkiller]

I made another rocket today. Fuse was made of tape and KNO3/NaNO3 powder. Casing was made of plastic and nozzle was made of thin metal. There was a 4mm diameter hole in the nozzle for fuse. The powder was pressed inside with pencil . It did not fly again. After burning, there was a lot of smoke and casing was burn away. What did I do wrong, again?

[50caliber]

What are the ratios of your fuel? you might need to put more pressure on the propellent

[poisonkiller]

Ratios are about 60/40 and if I press this powder in, turning it upside down a little powder falls always out.

[50caliber]

try adding more potassium nitrate or try the 63 kno3, 27 sugar, 10 sulfur propellant, it works every time for me

[oriansbelt]

Well if the casing was burnt away then maybe it is too weak. The propellent might just be burning through the casing and not going through the nozzle. And how thin was the metal for the nozzle? I think the thinest it could be to work would be 1/64"ish.