kpknd Posted April 1, 2013 Share Posted April 1, 2013 I built a model specificaly for the 8oz. motor and it works great. The model will also accomodate a 1lb. motor. Will get video when the weather is good. Link to comment Share on other sites More sharing options...
Oinikis Posted April 2, 2013 Share Posted April 2, 2013 what is the type of the motor? what fuel, and measurments? Link to comment Share on other sites More sharing options...
kpknd Posted April 2, 2013 Author Share Posted April 2, 2013 The motors are core burners made with 76.2 15.3 8.5 black powder. It is full strength BP with less sulfur, they have worked very well since I lowered the sulfur content. It is ball milled (one pound) for one hour then a few grams (3 or 4) of motor oil is added to make it less dusty and milled for another 15 min. to mix it in. Link to comment Share on other sites More sharing options...
Turbo Posted April 3, 2013 Share Posted April 3, 2013 I AM NEW TO THIS SITE AND NEW TO ROCKETRY.. I CAN'T SEEM TO OPEN A NEW TOPIC IN ROCKETRY SO I GUESS I CAN JUST ASK IT HERE. I HAVE VARIOUS BRANDS OF COMMERCIAL BLACK POWDER IN JUST ABOUT EVERY GRAIN SIZE FROM 1F ALL THE WAY DOWN TO MEAL POWDER, SO I DON'T NEED TO MAKE MY OWN FOR ROCKETS. THE PROBLEM THAT I AM HAVING IS THE ROCKETS ARE BLOWING UP BECAUSE THE BURN RATE IS SO DAMN FAST. I'VE ADDED CHARCOAL TO TRY SLOWING IT DOWN AND EITHER IT HAS WEAK THRUST SPOTS OR STILL BLOWS UP. I'VE HAD A FEW WORK FINE, BUT IT WAS OUT OF LUCK. I EVEN TRIED MIXING THE BP TO THE POINT THAT IT LOOKED LIKE MUD AND AFTER A WEEK OR 2 DRYING TIME THEY STILL BLEW. I JUST BOUGHT AN H FRAME HYDRAULIC PRESS FROM HARBOR FREIGHT TODAY, AND I WAS HOPING YOU GUYS COULD GIVE ME SOME IDEAS ON WHAT I COULD ADD TO MY COMMERCIAL BP TO GET MY ROCKETS FLYING. THE SIZE ROCKETS I AM MAKING ARE 3LB 1" ID. I HAVE THE TOOLING FOR THEM THAT I BOUGHT FROM WOLTER. I ALSO HAVE A 6LB BALL MILL AND PLENTY OF CHEMS SINCE I'VE BEEN A SHELL BUILDER FOR QUITE A WHILE. I AM MEDICALLY RETIRED FROM THE NAVY. I HAD MY LEFT LEG AMPUTATED ON ACTIVE DUTY SEVERAL YEARS AGO, AND THERE ARE TIMES WHERE I AM CONFINED TO MY HOUSE QUITE A BIT. THIS IS ONE HOBBY THAT HELPS PASS THE TIME. WELL, IF ANY OF YOU COULD HELP ME OUT, I WOULD REALLY APPRECIATE IT... Link to comment Share on other sites More sharing options...
nater Posted April 3, 2013 Share Posted April 3, 2013 (edited) One thing to consider is the hardness of the grains of commercial BP. It is going to be difficult to press them hard enough to consolidate into a single grain of fuel. Also, traditonal core burning BP rockets benefit from slower powder, especially larger motors like you are building. Due to the surface area along the length of the core, it is easy to exceed the strength of the paper tube. This brings me to my next point. What kind of tubes are you using and are you using a support sleeve when you press the motors? Most of us make our BP rocket fuel with no or small amounts of binders to keep the grain soft and easy to press. If you prefer commercial powder, try to get fuse powder. It is a slower burning, fine BP which many people have success as rocket fuel. It can be purchase for about $1 / pound so you cannot beat the economy of it. Edited April 3, 2013 by nater Link to comment Share on other sites More sharing options...
BurritoBandito Posted April 3, 2013 Share Posted April 3, 2013 I too am new to this site/rocketry and cannot seem to figure out how to make a new post, any help with that would be greatly appreciated. To the OP... I would try to add a bit of dextrin to the gunpowder, I believe that is what's used in Estes engines. Also make sure to use a convolute wrapped tube, spiral wrapped tubes have weak points at the seams. Try to keep detailed documentation of everything that you do and the end results. This will allow you to make small changes at a time and isolate problems more easily. I read somewhere that the best motor is made by making one that consistently blows up and then just widening the nozzle a little bit at a time until it no longer explodes. Good luck and let us know your results. Link to comment Share on other sites More sharing options...
BurritoBandito Posted April 3, 2013 Share Posted April 3, 2013 Sorry.. My reply was not for the OP. my bad. Link to comment Share on other sites More sharing options...
kpknd Posted April 3, 2013 Author Share Posted April 3, 2013 I have heard that baking soda could be added to regular balck powder to slow down the burn rate, mutch like is done for colored smoke. Using store baught BP sounds rather expensive, making your own for fireworks is alot cheaper. One pound of black rifle powder costs a lot more than a pound of potassium nitrate. Fuse powder sounds interesting, I will have to look into that. If it is workable all I would have to do is mill it with a little oil. Link to comment Share on other sites More sharing options...
Aquarius Posted April 3, 2013 Share Posted April 3, 2013 Go nozzleless. In short: Make your motor without the clay nozzle. I have tried a few and they work surpisingly well with hot BP as fuel. Link to comment Share on other sites More sharing options...
pyrokid Posted April 3, 2013 Share Posted April 3, 2013 If you have chemicals, and you have resorted to adding water to your commercial BP, there is no reason not to make normal rocket fuel. 6-3-1 KNO3 Charcoal Sulfur. Mix these by hand, wet them, and run the dough through a screen. Since the granules won't have a binder, you'll be able to consolidate them properly. These ideas apply to cored BP rockets. Link to comment Share on other sites More sharing options...
nater Posted April 3, 2013 Share Posted April 3, 2013 If you want to use fuse powder for nozzled, cored rockets, there is no need to process it any further. Just use it as it comes. Link to comment Share on other sites More sharing options...
psyco_1322 Posted April 3, 2013 Share Posted April 3, 2013 If you want to use fuse powder for nozzled, cored rockets, there is no need to process it any further. Just use it as it comes. How does that fuse powder compare to 6:3:1 in the rockets? Link to comment Share on other sites More sharing options...
nater Posted April 4, 2013 Share Posted April 4, 2013 How does that fuse powder compare to 6:3:1 in the rockets? Pretty close. Dagabu has played with it much more than we have. Maybe he will chime in if he sees this thread. Link to comment Share on other sites More sharing options...
kpknd Posted April 4, 2013 Author Share Posted April 4, 2013 Where do you find fuse powder? Link to comment Share on other sites More sharing options...
nater Posted April 4, 2013 Share Posted April 4, 2013 (edited) Where do you find fuse powder? PGI, from this guy: http://addictedtobla...wder.com/2.html . Looks like I was wrong on the price, it is currently $2 / lb. Edited April 4, 2013 by nater Link to comment Share on other sites More sharing options...
dagabu Posted April 6, 2013 Share Posted April 6, 2013 Gosh, lots of stuff here to ponder. Lets get crackin! @ Turbo, Listen to Nate, ball mill that commercial stuff to a powder then do as Pyrokid suggests and just add some water and granulate it to keep the dust down. Go for the nozzleless design which is nothing but a regular core burner without the clay nozzle, fuel is used instead. @ Psyco, Fuse Powder is the same as 6:3:1 when compressed into a fuel grain. For $2.00 a pound, it is fantastic stuff. One word of caution, Jon is down in IOWA today at the spring meet (I can't go, SWMBO is making me go to another wedding) is likely selling the last of the Fuse Powder today, if not, it will likely be gone by PGI. Call Jon and see if he has any, he will hold it and deliver it to PGI if he does but you will have to pay upfront. We have a retired ESTES engineer online, Ed Brown and I can say for certian that Dextrin was not used to make the fuel grains, ridiculously high pressures and water are the key. Is Ed here Mum? Lets ask him directly about the design, he cant answer some of our questions but I ma sure he will find a way to work out an answer to our queries. @ kpknd, don't use baking soda to slow BP, you will just be making a soda blaster and if used in a clay nozzled motor, it will erode the nozzle or clog it up and cause an over pressure. @ Nate, hey bud! You have a nice little test rig I hear, could you show us a few curves for the #1 motors you have fired? You may have the answer already in the curves. Dag Link to comment Share on other sites More sharing options...
kpknd Posted April 6, 2013 Author Share Posted April 6, 2013 Still witing for the weather to cooperate. Then Operation Blast Off will commence, with pictures and video. Link to comment Share on other sites More sharing options...
nater Posted April 6, 2013 Share Posted April 6, 2013 Dag, I have not made a pyro rocket since late last fall when we taught a 1# BP motor class. Our Winter shoot site is not a good site for rockets, so I brought shells and had some problems with them surviving the lift. I have been sidetracked by that all winter and decided that I like spiking cylinders more than I like pasting ball shells. The last few shells I lifted performed good, so I will be back to rockets shortly. (I did build a fibergless level 1 capable HPR rocket, but that is another topic) Link to comment Share on other sites More sharing options...
Mumbles Posted April 6, 2013 Share Posted April 6, 2013 If Ed is a member here, I'm unaware of it. Link to comment Share on other sites More sharing options...
dagabu Posted April 7, 2013 Share Posted April 7, 2013 Dag, I have not made a pyro rocket since late last fall when we taught a 1# BP motor class. Our Winter shoot site is not a good site for rockets, so I brought shells and had some problems with them surviving the lift. I have been sidetracked by that all winter and decided that I like spiking cylinders more than I like pasting ball shells. The last few shells I lifted performed good, so I will be back to rockets shortly. (I did build a fibergless level 1 capable HPR rocket, but that is another topic) Sorry to hear about your winter shoot site, up here we had three foot of snow on the ground, NO chance of lighting anything on fire! It's spring so you had better start on your competition rockets and shell, I am only volunteering at manufacturing this year so no building for me or the boy. I would love to see some pics of your rocket, email me? Dag Link to comment Share on other sites More sharing options...
kpknd Posted April 8, 2013 Author Share Posted April 8, 2013 I will try to post a couple of pics tomorow,Mon. Link to comment Share on other sites More sharing options...
nater Posted April 8, 2013 Share Posted April 8, 2013 Sorry to hear about your winter shoot site, up here we had three foot of snow on the ground, NO chance of lighting anything on fire! It's spring so you had better start on your competition rockets and shell, I am only volunteering at manufacturing this year so no building for me or the boy. I would love to see some pics of your rocket, email me? Dag Just in case anyone else was interested in the pictures too: http://www.amateurpyro.com/forums/topic/8401-dual-deploy-eagle-child/ Our shoot site for the Winter was a golf course. It is a fun site, but imperative that all debris is cleaned up. I could not come back the next morning and didn't want to spend all night tracking down rocket sticks, so I only brought shells. Link to comment Share on other sites More sharing options...
kpknd Posted April 8, 2013 Author Share Posted April 8, 2013 I will try to post a couple of pics tomorow,Mon. Sorry, am having troubles posting photo. Link to comment Share on other sites More sharing options...
dagabu Posted April 8, 2013 Share Posted April 8, 2013 (edited) Yea, its kind of complicated here. Go to the gallery and upload your pictures there and then right click on your saved image and select "Copy Image URL" then paste that URL into the field after you click on the picture icon at the top of your post. I.e.: Here is your rocket: Edited April 8, 2013 by dagabu 1 Link to comment Share on other sites More sharing options...
kpknd Posted April 8, 2013 Author Share Posted April 8, 2013 Meteor II scratch built rocket Link to comment Share on other sites More sharing options...
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