Rocket Succes!

[papasmurf]

I've been lurking on here for quite a while and have posted a few topics. I’ve mostly been searching, reading, and digesting everything on this forum. I joined this forum so I could learn more about black powder rockets, and thought I was ready to make the leap from sugar rockets. My first step was to read, read and read some more. Then I purchased the united nuclear rocket factor kit a few months back. The first thing that attracted me to this kit was the price tag and the fact it had everything I needed to get started. All my chemicals I purchased from Hobby Chemical Supply.

 

I made 600g of meal powder with this kit and was reasonably pleased with the burn rate. My black powder mix was 75/15/10 (KNO3/charcoal airfloat/S), I think this may be a little hot for nozzle rockets.

 

I also purchased some 3/4" tubes of which were all useless with this kit. The literature that came with this kit did say that the tooling was for use with 3/4"PVC pipe, oh well my mistake, I took a gamble and hoped it would work (the kit does fit the 3/4” tubes but is so tight that I thought I was going to have cut the tube off my tooling). Not wanting to CATO a PVC pipe on my first rocket attempt I rolled my own tubes to match the I.D. of 3/4" pvc pipe using 2 parts wood glue, 1 part alcohol, and 1 part warm water and contractor’s paper I picked up at Lowes. I'll probably use PVC for when I want to make a recoverable rocket.

 

For my nozzle mix I used bentonite clay with 5% mineral oil added. My fuel mix was my meal powder granulated using a spray bottle that had distilled water and 10% dextrin added to it. I used a fine mesh kitchen colander to granulate my meal powder. Once dry and rescreened I then added 5% 80 mesh charcoal to it to complete my rocket fuel. I put some pipe clamps around my rocket tube and used a 4lb dead blow hammer to ram both my nozzle and fuel (about 10 blows each). I added a small report in the remaining space to finish her off.

 

I was pleased with how well the rocket looked; the nozzle was hard, smooth and shiny. I waited till dusk on Saturday evening at a family cookout and successfully fired off my first black powder rocket. The rocket took off a lot faster than expected and I was extremely pleased with its performance, it flew to approx. 1,000+ feet give or take a 100’ (it was a good second after I saw the bang from the header to when I heard the report). My family and friends who all watched were all surprised by my performance, especially those who saw last year’s sugar rocket go only 30 feet high and whose comments were “is that it”.

 

I can’t wait to get better headers on it with some good effects. I already have some good ideas from the turbo payro manual that are easy and within my experience. I wanted to thank everybody on this forum for my success, for if it wasn’t for the information contained on here I wouldn’t have gotten this far.

If you have any suggestions or comments on my rocket configuration feel free comment.

Thanks!

Edited July 8, 2013 by papasmurf

[Bobosan]

Congratulations, papa. It's always a thrill to watch a rocket you create take to the air successfully.

[brimstoned]

You are hooked now, buddy!

I hope to see a vid of one of those shortly...

[Juiceh]

Nice!! A rocket built with a UN kit was my first home made rocket motor and first success. I remember lighting that fuse and running like hell. I used good 30s fuses back then. It lept out of the launch tube with an awesomely pleasing whoosh sound and fire trail with a fast take off. I was so psyched it didn't CATO.

 

Make sure you optimize that mill. 6 hr milled BP at optimal speeds is a whole different ball game from 6 hr milled BP in the stock mill configuration.

 

What tubes did you try? I've had success with spiral wound tubes from ihaveadotcom.com and NEPT tubes from Hobby Horse for nozzled BP and nozzleless bp motors on that spindle. NEPT is the best.

 

Is it the spindle or rammers that don't fit the tubes well? Try taking a 6-8 inch metal or wood rod of about 3/8 diameter and "wallowing out" the inside edge of the tubes in a swirling motion, preferably with the direction of the paper layers. I do this on all my tubes before I start pressing a motor, It makes a world of difference. I haven't used the UN kit in a long time, I do this with my tubes no matter what tooling I'm using. Lots of the tooling out there can be a tight fit sometimes. If I have time after cutting a batch of tubes I use a modified plumbob mounted on a drill press to flare the ends out a little.

 

I never got around to adding wax to the bentonite for my nozzles. I just used plain bentonite, I have been planning on making some bentonite\wax mix for the next time I make nozzled motors. I have had no erosion issues with coreburner BP motors in my static motor tests. I don't know how the nozzle held up in the only endburner I've made, never recovered it after launching it.

 

You can make nozzled sugar rockets using the UN kit, I have. But they can't carry much, use a short delay and salute in the end of the tube is as far as I would go for payload.

 

The UN spindle is very close to the Hybrid Universal spindle so you should be able to make all sorts of motors with it if you have a press. I have never tried pressing a motor with my UN kit. I have heard the nylatron rammers are too "squishy" but I don't know. Next time I get a chance to press some motors i will give it a whirl.

[papasmurf]

I milled my BP 5 hr, and one batch I did it for 9 hr just to see if there was a difference in burn. I really didn’t see any difference. What else can I do to optimize the mill? I thought about buying more media so the jar is about half full. But, doing that might exceed the 3lb capacity of the mill.

I got the tubes from pyrodirect.com, at the time they had the best buy including shipping. I could get the tube on and off the spindle fine, but the rammers were the problem. I tried widening/stretching the tube by shoving and tapered oak hand rail picket in the tube. It helped some but the tubes were still so darn tight. I thought about drilling a small hole in the end of each rammer to make some puller holes, but am cautious, don't won't to mess the tooling up since I use both ends to ram.

I initially wasn’t going to add anything to my nozzle mix, but noticed in a trial nozzle that a small amount of clay never compressed in the tube and when I turned the tube upside down and taped it about ¼ teaspoon fell out. I didn’t have any wax so I added mineral oil to help consolidate and bind the clay together better. It worked really well. I’m hoping to do a static test soon. To see how well my motor performs and then cut it in half.

[Juiceh]

The 3Lb tumbler you got with your kit is most likely an unmodified Chicago Electric rock tumbler, the same sold by Harbor Freight but with a UN label on it.

http://geology.com/r...ago-tumbler.jpg

 

I run my modified 6Lb version with both barrels half full of lead media, 200 .50 lead balls, half full is optimal. It does need a push to get it going. Get some real hard lead milling media from: Leadball@brightdsl.net The lead balls that come with the factory kit are muzzle loading rifle rounds, they will start to show signs of wear and begin to deform very quickly.

 

Before you start to try to modify the tumbler you got from UN you should check to see if they have modified it themselves. I have never bought a tumbler from them so I don't know if they do or not. Put the barrel on the mill(with media) and put a piece of tape on the black rubber portion of the barrel. Now you are going to want to run the mill and record how many times the barrel revolves in 10 seconds by counting the passes of the piece of tape. Easiest way to do this is with a video camera. Once you have that number multiply it by 6 and that is your rpm of the barrel. The optimal speed for the barrel sizes with these tumblers is approximately 85 rpm. If your number is much lower than that it is not optimized.

 

Check the diameter of the drive roller. Standard diameter is about 1/2" I think. You will need to remove the drive roller from the tumbler and install a thicker piece of hose over it. A pair of snap ring pliers are needed to easily remove the snap rings that hold the plastic bearings in place. The O/D of the new hose I use is 3/4", this gets the rpm right into the butter zone for the 6lb model. I use some cheap clear tubing from home depot. I highly recommend taking the drive roller to home depot to find the right fit. Then just slather gorilla super glue all over the original drive roller and slide the new piece of tube over it, wipe off excess at the ends, and give it 24 hours to dry before use.

 

When you reassemble the mill swap out the belt for a heavy duty one from pyrocreations: http://www.pyrocreat...c/sdetail/22589

 

You can also increase the diameter of the unpowered roller to reduce the strain on the motor.

 

Once that mill dies, and it will. These little tumblers do eventually with heavy use. Go out and get a 6lb one from harbor freight with the warranty. I've gone through quite a few of them and I think I only paid for 2 when they were on sale for like $40. Never return them with the barrels and you will wind up with a nice collection of barrels for dedicated purposes. Much easier and cheaper than calling and ordering new barrels. Plus, might not be a good idea to give them barrels with BP residue in them.

 

In order to see the difference longer milling accomplishes at stock speeds you would probably need to mill for about 24 hours. Simple burn tests won't always give you a great idea of how fast the powder is, but the 3" mortar baseball test will!

 

Extended milling really sucks when you want to bang out lots of really good BP used for lift. Not to mention the time wasted you could be milling other stuff. I use my other drums for milling perchlorate with catalyst for whistle rocket fuels with dedicated drums & ceramic media for 6 hours. I also do 6 hour runs with dedicated drum & ceramic media for milling strobe compositions minus the metals, for strobe rockets. DO NOT MILL COMPLETE WHISTLE OR STROBE FUELS! I don't recommend milling anything but BP comps for a newbie. Whistle and Strobe fuels are very powerful and sensitive and should not be attempted until you have mastered BP rockets.

 

After you modify your mill you will notice that it is louder during operation and has a much different sound. This is because the milling media is now cascading and falling from the top of the jar rotation and coming down much harder on the barrel surface\other lead balls\chems. Whereas before all the lead media was just rolling on the bottom half of the barrel as it goes.

 

*Edit*

The only time my mill needs a push start is with heavy lead media. With lighter ceramic media and 2 fully loaded jars it takes off with no assistance. Lead is best for BP.

Edited July 12, 2013 by Juiceh

[papasmurf]

wow, thanks for all the info! i'll look into it and see if its been modified. I had forgotten about alot of that info about ball mill efficieny. thanks for the reminder.

 

to help my mill out some I did tilt the mill up some so that the mix and media would stay near the bottom. my thinking was that, this would help the media tumble more. not sure what real effect this was having on the bp. some test are deffinitely warranted to find out.

 

it will be quite a while before I get into other fuels, for one thing I dont have a press. and now the the 4th has come and gone its back to some projects around the house. so it'll be while before I get any time to experient.

 

thanks again

[Juiceh]

Don't tilt it. Just get the rpm to optimum speed and you are good to go.