Black Powder Rockets

[oskarchem]

Well, if I were you go with the old BP and the tube/nozzle size and all of that. Because it could take you some time to tune the new nozzle diameter to the new BP.

[s1xfiv3tw0]

Today I had the second successful launch in a row of an end burning rocket. I used the last of my Cowboy Brand charcoal BP, not really fast. I also put a very small BP salute (firecracker size) on top to test what I have learned here, about passfire to a header etc. Worked perfectly, timing was a little off since it didn't pop until it was on the way down. But it worked!!

 

I have made up a new batch of BP using "Real Montana" brand maple charcoal and this stuff is really fast. Meal powder goes up in just one "poof", should I start from scratch or take what I have already learned nozzle size,tube dia.,tube length and go from there?

 

Just a quick note about "Real Montana" charcoal. The packing could have been better but if the post office didn't mind getting a little dirty it doesn't bother me. I purchased samples of Maple,Birch,and Alder for a $1 a pound. The samples were mixed about 50/50 small/medium pieces and about 95% were completely cabonized, a real steal for the price.

 

Hey, I am trying the same thing as you. What was your rocket's ID/OD and did you have a nozzle? If so, what was the diameter? Thanks.

[nickle]

Hey, I am trying the same thing as you. What was your rocket's ID/OD and did you have a nozzle? If so, what was the diameter? Thanks.

 

 

Thanks for asking s1xfiv3tw0 I am by no means an expert but I am learning. I am taking baby steps towards maybe launching some big one's one day. My rockets are very small compared to some of the ones on this site.

 

I hand roll all my tubes using plain white printer paper, the cheap stuff you get from Walmart, using a 7/16 stainless rod and held together with Elmers glue. The length is 5in., OD 9/16" (.560), ID 7/16" (.437), and the nozzle is 9/64' (.140). I use the cheapest cat litter I can find ground in a coffee grinder for the top and bottom plug and then drill the nozzle. This seems to work for me and I hope it helps get you on the right track.

 

I just launched another with the new batch of powder (much faster) was a bit afraid of a cato but worked like a champ with the same dimensions. Went much higher with this new charcoal (maple) more reactive I guess.

Edited October 28, 2008 by nickle

[s1xfiv3tw0]

Thanks for asking s1xfiv3tw0 I am by no means an expert but I am learning. I am taking baby steps towards maybe launching some big one's one day. My rockets are very small compared to some of the ones on this site.

 

I hand roll all my tubes using plain white printer paper, the cheap stuff you get from Walmart, using a 7/16 stainless rod and held together with Elmers glue. The length is 5in., OD 9/16" (.560), ID 7/16" (.437), and the nozzle is 9/64' (.140). I use the cheapest cat litter I can find ground in a coffee grinder for the top and bottom plug and then drill the nozzle. This seems to work for me and I hope it helps get you on the right track.

 

I just launched another with the new batch of powder (much faster) was a bit afraid of a cato but worked like a champ with the same dimensions. Went much higher with this new charcoal (maple) more reactive I guess.

 

Thanks. I have a question for drilling a nozzle. Did you do it by hand or used an actual drill? Whenever I do it, it crumples and falls apart.

[JS92]

Thanks. I have a question for drilling a nozzle. Did you do it by hand or used an actual drill? Whenever I do it, it crumples and falls apart.

 

If it crumbles, you need to compact the clay better and harder!!!

[Mumbles]

Any time you are drilling into comp, use a hand drill. You want to keep friction down as much as you can for obvious reasons.

[nickle]

Maybe someone can help me with my end burners. The rockets fly straight and true until all the fuel is expended. Instead of arcing over in the direction of flight, as expected, they do a backward roll taking them back to me and the launch area. This happens even when launched even at a 60deg. angle away from me. What am I missing here, center of gravity, weight distribution, stick length etc.

The prevailing wind's are always in the direction of flight so I can't see that as a reason. Any ideas?

[Mumbles]

Rockets turn back into the wind because of the stick.

[nickle]

Rockets turn back into the wind because of the stick.

 

 

I understand the weather vane effect however this seems to be carrying things to an extreme. That a rocket that reaches a max altitude of maybe 250 feet on a good day, can travel an equal distance into the wind without power plus gravity. This works out to be almost an equlateral triangle, I don't think I could design this effect if I wanted to.

 

I was not the best physics student, so is there anything I can do to bring the rocket down to earth sooner, shorter/longer stick,more weight etc?

[tentacles]

This is precisely why you're supposed to install a stick detacher to the top of the rocket motor. Put in a bit of delay to activate it near the apex of the flight. 20 grams is good for a 1lb rocket, and ensures a proper separation sequence.

[s1xfiv3tw0]

If it crumbles, you need to compact the clay better and harder!!!

I compacted it very good. About 5 rubber mallet hits and rotating the rammer each time. The clay I am using is just kitty litter, not milled at all. Could this be the problem? It is about the size of a grain of sand.

 

 

Any time you are drilling into comp, use a hand drill. You want to keep friction down as much as you can for obvious reasons.

Thanks for your help.

[tentacles]

Kitty litter is perfect, although you might want to mill it in a coffee grinder just a little (get a finer range of particle sizes). You don't want to turn it to dust, but you want some dust in there, especially if you're ramming it. Does your rammer fit the tube reasonably well? IE within .020" or so? A loose fit will give you problems as well.

[JS92]

Also, this sounds silly but could be a plausible reason, is your kitty litter wet? Is it stored in a damp place?

 

does anyone know if it was to be wet, would it make it more likely to crumble?

[TheSidewinder]

I compacted it very good. About 5 rubber mallet hits and rotating the rammer each time. The clay I am using is just kitty litter, not milled at all. Could this be the problem? It is about the size of a grain of sand.

 

1) 5 whacks most likely isn't enough.

 

2) I'd get rid of the rubber mallet. You need a dead-blow or a solid head. Rubber "bounces" too much, and a lot of the energy is wasted in a "rebound effect".

 

Some folks use a rawhide mallet. I use a 2-pound short-handled steel sledge, and hit it 7-10 times.

 

You will also need a sleeve, as I've come to discover.

[nickle]

I tried my first core burner today and as usual things didn't go as planned. I used my standard 75/15/10 end burner mix and managed to do the following:

 

1) blow the nozzle out

2) the BP salute header went off at about 10ft.

3) the delay charge burned about a 1/4 sec at the most before igniting the header

4) the rocket itself continued on to about 100ft. altitude even after header went off

 

My conclusion was that the BP was much to fast for a core burner. The core and nozzle are already 1/3 of the tube ID (.437, nozzle/core .140). I still have about 1/2 lb. left and don't want to waste it. Should I use this powder for end burner only? How do I slow this powder down?

Edited November 9, 2008 by nickle

[Mumbles]

You could stick with it for end burners only. Another option would be to make nozzle-less rockets. These are core burners without a clay nozzle, just BP. They're pretty neat, and from what I hear are pretty difficult to CATO.

 

To cool it down, I'd suggest adding about 22g charcoal per 100g of comp. This will approximate a 6:3:1 ratio. To get exact you'd need 22.5g charcoal, and 2.5g sulfur.

[nickle]

Thanks for the advice guys. I will give the nozzle-less ones a try as well as slowing a small amount of powder down for the core burners. Probably will have to experiment a little since I gave up on rolling my own tubes and bought some NEP tubes , which I hope UPS brings tomorrow. Edited November 10, 2008 by nickle

[WarezWally]

I've been messing around with my mini lathe for a bit now and have made a few sets of rocket tooling mainly for shits and giggles. If any aussie wants some tooling made I'm willing to give it a shot for material costs + beer money.

[ActionTekJackson]

Thanks for the advice guys. I will give the nozzle-less ones a try as well as slowing a small amount of powder down for the core burners. Probably will have to experiment a little since I gave up on rolling my own tubes and bought some NEP tubes , which I hope UPS brings tomorrow.

 

 

Well, I know most of the time they say to slow down the mix when you get CATO's or try nozzless (still a good idea), but keep in mind that its not always the "best" solution. The most frustrating time I EVER had with rockets was trying to make my formula match my tooling. Failure after failure, not enough lift, or CATO seemed the most prevalent issues. So my buddy was like hey... I've seen super fast rockets on APC and they seem to all be using the same type of tooling and strong tubes, so... maybe its the process. So I tried it again, taking every precaution, tiny increments of BP rammed at a time, used PVC at the time cuz I wanted to make sure it wouldn't CATO as easliy (not my reccomended plan), and what do ya know? A decently fast BP worked great! Ok, lets test this, lets use the fasted BP we've got (trust me, its fast as hell!) followed the same process, very small increments Rammed very well, and LOTS of patience (it gets better over time), again worked great. Oh shit, falling PVC of spent rocket could kill someone! (rocket stuck straight into the ground about 3 inches, that would have punctured someone's skull...) Ok, ordering paper tubes... made a sleave for the tubes, you can use a metal (preferably Aluminum) tube that your paper tubes slide into smoothly, or do what I did, take a 2x4 cut two peices, each slightly longer than your paper tube. use a drill with an abrasive sandpaper cylindar bit, and sand out half the diameter of the tube in each peice of 2x4 so that the tube fits completely between the peices allowing the 2x4's to touch together completely, then bolt these together. I suggest wingnuts for the bolts, much faster to loosen to remove your rocket.

 

Here's some vids of my stuff, you can tell the slower one's from the faster one's both are HUGE improvements to where i was before (the same issue you are having) *I'm not sure how to post working links on the new forum here, so copy and past it is, sorry* http://www.youtube.com/user/actionjacksonducane

[Zmuro]

My first BP rocket: 19mm ID BP Rocket With 3in Head

[Gunzway]

Zmuro, Very nice rocket plus header! A+!

[andyboy]

I concur with the previous poster, great stuff.

[Richtee]

My first BP rocket: 19mm ID BP Rocket With 3in Head

 

Sweet! Just as a sidebar...how many pyro vids feature the "barking dog" soundtrack? LOL!

[Gunzway]

Sweet! Just as a sidebar...how many pyro vids feature the "barking dog" soundtrack? LOL!

Oh 50% of all my videos feature that soundtrack. My damn dog is the type to try eat the fire. I gotta watch out for him. But I got like eight dogs all in a row of my house. You walk out and close the gate a little too hard and they begin barking. It's a real pain :/

[pyrogeorge]

 

17mm I.D BP rockets

Edited March 16, 2009 by pyrogeorge