FrankRizzo Posted January 10, 2008 Posted January 10, 2008 About the press, I strongly suggest building one yourself if you've got access to a welder and a basic machine shop. The ones you get from Harbor Freight require a lot of extra shimming and reinforcing to make them good enough for pressing rockets without bending your spindles. If you start from box channel and build it yourself, you have full control over the design parameters. Dan Williams has a real nice design for a bottle jack powered press on his new site: The Big Brother Hydraulic Press Wheel weight lead will work for milling media. They'll wear and contaminate your powder with a bit of lead dust, but you can't beat the economy.
pyro6314 Posted January 11, 2008 Posted January 11, 2008 Can you buy antimony anywhere? Does lead dust really matter that much in BP? My co-worker mechanic saves all sorts of ball bearing balls; we **JOKE** about making a shrapnel bomb for a group of people nobody likes in our town. Im sure I could snag some for milling inert materials. Would the ball bearings be OK for milling aluminum or will it readily combust when it gets fine? The press wont be a cheapy Chinese built press. How do you bend your spindles? If it slops sideways or how do you mean? Im sure I can convince my dad to shell out for a American/Canadian built press.
Mumbles Posted January 11, 2008 Posted January 11, 2008 Ebay sells antimony pretty cheap. The thing is you can't just toss it into the molten metal. You must heat it higher than the MP to get it to alloy. I think up around 700 celcius or so. It's much easier to buy high antimony lead. I believe some reloading places sell 5lb bars of 20 or 25% antimony lead. One bar would be enough for 1 milljar worth of hardened lead. Yes, SS should be ok for milling inert materials. Might also want to look into ceramic.
pyro6314 Posted January 11, 2008 Posted January 11, 2008 Im sure I will have no problem heating it up to quite a ways past that. My casting rig is pretty ghetto. I welded a cap and handle on to a piece of 4 inch pipe and I heat it with a blow torch. SS probably wouldnt be safe for aluminum Im guessing? Ive heard you need to open the container once in a while so the aluminum will oxidize a bit to prevent it igniting upon introduction to O2? I would like to make use of all my (and others) aluminum turnings from a lathe. Run them through my Ice Crusher (maybe?) so they arent so long then throw em in... Could take what, a week or two with some decently hard media.
asilentbob Posted January 11, 2008 Posted January 11, 2008 How big are the bearings? The bigger the bearings the easier to mill big pieces up into smaller pieces... however milling these pieces up into very very fine flake with big media alone would take awhile. I would try to use a mix between about 3/8" and 3/4" OD personally. So yes Steel/SS is fine for milling aluminum. Though actually... what you might want to do is get some steel rods and cut them into cylindrical media and grind down the rough ends so they are not so sharp. These will have more surface area and mass than spheres so they should make the milling faster. Yes you must occasionally open the milling container so that the freshly exposed un-oxidized aluminum surfaces can get an oxide coating progressively... otherwise going from like foil to a very small particle size like -200 mesh without "burping" the jar... there would be so much exposed surface area that the freshly introduced air would oxidize the aluminum with the release of a lot of heat... possibly just getting very hot... possibly bursting into flames... The term to describe material that burst into flames often on exposure to air is to say that it is "pyrophoric." The aluminum milling in the container (if the container is airtight) will mill and react with the oxygen in the container to form some Al2O3 surface oxide... however the oxygen in the jar will get depleted and you will be milling in essentially inert nitrogen after a short while... Different people give different schedules for opening the container. It would be nice if a milling container for milling metals was made with a air filter of some kind that wouldn't get clogged so that there would always be enough oxygen in the milling container to satisfy the need for the Al to form its oxide layer... Or some sort of forced air system... using perhaps plastic tubing and swivel fittings... with air in and air out lines... having perhaps a -200 screen on each that is protected by a 20 mesh SS screen... then running the air out line though some liquid to trap any escaping aluminum... When I say forced air... I don't mean like pumping a lot of air though... just a trickle... much less than a aquarium aerator. Hmm... could be done... with trouble... but would it be enough to not have to burp the container still?
pyro6314 Posted January 11, 2008 Posted January 11, 2008 Sounds good, but first I will need to finish my damn ball mill. My design is crap but now that I found a good motor Im going to go to town tomorrow and buy some stuff (pulleys, belt, new bar stock and bearings). So pretty much Im starting over. A DC motor would be nice though so you could use PWM to control the speed. Maybe I will keep looking cause Im impatient and want this thing to be efficient.
pyrogeorge Posted May 24, 2009 Posted May 24, 2009 has anyone got plans or dimensions to make rocket tools?
BPinthemorning Posted May 24, 2009 Posted May 24, 2009 Check my gallery. It has 1LB tool specks for coreburner. If you search the forum (like with the search button, not just paroozing) there are specs for like every rocket imaginable...
firetech Posted May 27, 2009 Posted May 27, 2009 Anyone have 4oz core burner tooling specs? BP varies so I can lengthen or shorten the spindle if need be, I just want a reference for a starting point.
FREAKYDUTCHMEN Posted May 28, 2009 Posted May 28, 2009 You shouldn't adapt your tools, you should adapt your fuel So cato's means you need less powerful propellant, and if your rocket doesn't get from the ground you need a hotter fuel.
firetech Posted May 28, 2009 Posted May 28, 2009 I thought about that, but I'd like to use straight BP for everything I can. And since I have the option to do so, I will adjust the spindle accordingly.
Mumbles Posted May 29, 2009 Posted May 29, 2009 If you're using straight BP, do yourself a favor and start with end burners. You'll be blowing up a lot of core burners if your BP is any good. Might I suggest using BP as a base, and adding charcoal until they stop blowing up instead of changing the spindle. Here are the guidelines. This is true for basically any size. You should be good to go. Tube - 10x IDNozzle - 1/3 IDCore - 7x ID tapering from 1/3 ID to 1/4 IDNozzle - 1 ID thickInset - 1/2 ID So, lets review. Round stock the ID of your tube that is 1/2 ID long as the inset. On top of this a core that is 6.5 to 7x ID long with a slight taper. Around 3 cored rammers, and 1 flat rammer. It will help to put a taper on the nozzle to prevent errosion, and improve thrust. A 30 degree angle on both sides is pretty standard. I'd also suggest a slight lip around the edge of the rammer that makes the nozzle(angled), around 1/32" to prevent blow by of fuel, and to help seat the nozzle well. End burners, start with 1/4 ID nozzle diameter. Make the "core" a little longer than your nozzle, and away you go. 2
firetech Posted May 29, 2009 Posted May 29, 2009 Thanks Mumbles. I've had great success with 4oz , I prefer the slow takeoff that they have but I can't attach headers exceeding 50g on them. Thats when I need to switch over to core-burners. A friend of mine actually has made tooling for a core burning BP rocket although it looks a bit abstract compared to what popular suppliers sell. I'll give the dimesions you offered a shot and let you know how it goes.
Mumbles Posted May 29, 2009 Posted May 29, 2009 60:30:10 KNO3-C-S is a pretty standard mix for the above tooling specifications. Some will add some coarse charcoal to enhance the tail. This is equivalent in parts to 80 BP, 18 Charcoal, 2 sulfur. Just because it is equivalent in parts, does not mean it's equivalent in power. The 6:3:1 ratio is simply screened from fine chemicals, not ball milled generally.
ActionTekJackson Posted May 30, 2009 Posted May 30, 2009 well, I can't remember who was asking for this but, someone wanted pictures of my homemade wooden rocket tube sleeve. I finally got some yesterday. So here they are :-) And yes thats my new press, and my fiance pressing a rocket! :-) Her's flew better than mine... darn women... ;-)
pyrogeorge Posted May 30, 2009 Posted May 30, 2009 I found some plans..i think that is usefullbp_rocket.pdfstinger_0.75.pdfstinger_0.75_launcher.pdfstinger_0.75_motor.pdf
cojonesm Posted June 25, 2009 Posted June 25, 2009 (edited) I just launched a rocket but it cato'd pretty fast. I'd press only 0.5cm of whistle above the core could that be the reason for it to cato? http://www.youtube.com/watch?v=E9b3f4QKHA0 Edited June 26, 2009 by cojonesm
Aquarius Posted June 25, 2009 Posted June 25, 2009 Kinda hard to tell what happened on that video...How does your regular drivers preform?
Aneantis Posted June 25, 2009 Posted June 25, 2009 Jup, there was to much pressure and so the top blow out. You have to press your ID (minimum!) on top of your core.
dagabu Posted July 10, 2009 Posted July 10, 2009 (edited) Here are my two old homemade tooling sets from the 80s. They are made from aluminum (not rusted, just the lighting) stock and Hysol 20-20 metal filled epoxy. Edited July 10, 2009 by dagabu
FrankRizzo Posted July 10, 2009 Posted July 10, 2009 Here are my two old homemade tooling sets from the 80s. They are made from aluminum (not rusted, just the lighting) stock and Hysol 20-20 metal filled epoxy. Very cool, Dave. I suppose you just chucked the spindle in the drill press and manipulated the epoxy to form the nozzle former?
Xtreme Pyro Posted July 10, 2009 Posted July 10, 2009 (edited) Here are my two old homemade tooling sets from the 80s. They are made from aluminum (not rusted, just the lighting) stock and Hysol 20-20 metal filled epoxy. Neat tooling dagabu it's pretty neat that your still using your tooling from the 80's. I figured i would post a couple pictures of my 4oz bp rocket tooling, that my dad made for me awhile back.. It's all aluminum.Ill post better pictures later when i get some time. Plans: (Mumbles gave me the link to these awhile back)http://www.truetex.com/bp_rocket.pdf EDIT: I just realized these are the same plans that pyrogeorge posted (the first pdf) Edited July 10, 2009 by Xtreme Pyro
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