derekroolz Posted July 1, 2009 Posted July 1, 2009 Something about you makes me question that you've been making anything for 2 years. Wow and your the ones saying need to watch my way of speaking to others. Because that is a straight up diss And btw friend i was in model rocketry for most the time I just recently have switched over to making rockets from stratch(including the engines.) And have been doing that for about three months now and still have never had a cato in both feilds.
firetech Posted July 2, 2009 Posted July 2, 2009 If I was a mod I would ban you for being a smartass and for overuse of emoticons.
Ventsi Posted July 2, 2009 Posted July 2, 2009 (edited) Well considering the post you made about using FP as lift charge with a PVC pipe , I think just about everyone has a bad hinge about you. So I recommend you either find another forum and try ato be a bit more mature and hont give any damn suggestions until you feel like you can. Cement? Really? First there is water invlolved, then drying times. Nevermind how the fuck you're going to take a cement nozzle off your tooling after its been curing on there for a few weeks. Edit:Oh yeah, don't diss the mods, they have way more knowledge than most of us , and there is a reason for who they are. Edited July 2, 2009 by Ventsi
flying fish Posted July 2, 2009 Posted July 2, 2009 If the person is being stupid enough to not creat a proper rocket, They obviousily dont know what the hell there doing.Cplmac (for instance) has had plenty of CATO's and believe you me, he is our resident expert on firework rockets. The whole point of experimenting with pyrotechnics is to learn something (in the safest manner possible of course - rocket CATOs can be wickedly powerful, especially when whistle mix is involved). If you don't experiment with new rocket designs, you might not get as many failures, but you won't learn anything new either. Also, if you are such an expert on rockets, what is this all about? I don't mean to offend you or anything, I just think you should stop telling experienced members that they don't know what they are doing . I am a complete noob to pyrotechnics, I have made a few fountains some were ok. I have tried multiple times with sugsr rockets...failed every time... what the hell are cored rockets and what do you use in the cores and what are your guys dimensions for your rockets: Nozzles height of the nozzles, size of the hole drilled in the nozzles, and i need to know the best mix for the rockets i have any type of sugar KNO3 and sulfer but am unable to get ahold of fe203 and titanium i can get al powder and magnesium powder but takes a long time to grind it down so HHHHHEELLLPPP!!!!! a fellow pyrotechnic ps: when you say kno3/su do you mean kno3 to sucrose you all will be incredibly helpful for your replies
derekroolz Posted July 3, 2009 Posted July 3, 2009 Cplmac (for instance) has had plenty of CATO's and believe you me, he is our resident expert on firework rockets. The whole point of experimenting with pyrotechnics is to learn something (in the safest manner possible of course - rocket CATOs can be wickedly powerful, especially when whistle mix is involved). If you don't experiment with new rocket designs, you might not get as many failures, but you won't learn anything new either. Also, if you are such an expert on rockets, what is this all about? I don't mean to offend you or anything, I just think you should stop telling experienced members that they don't know what they are doing . i never said that the others are not experienced in their rocketry but the quote above is the only way that i can see to get new designs to test out for later use and that is still learning something new... i already have tested most of the rockets here... i have a lot of chemicals and stuff already made up and way to much time with way too much land pn my hands
psyco_1322 Posted July 3, 2009 Posted July 3, 2009 / Lock This thread is gone way off topic and has now become grounds for arguing whose rockets are better. About everything there is to say about kitty litter as nozzle mix has been said. I vote lock.
derekroolz Posted July 4, 2009 Posted July 4, 2009 / Lock This thread is gone way off topic and has now become grounds for arguing whose rockets are better. About everything there is to say about kitty litter as nozzle mix has been said. I vote lock. there never was arguing going on
firetech Posted July 4, 2009 Posted July 4, 2009 It's about time you started capitalizing your letters and using correct punctuation. It degrades the forum.Thanks, Firet3chrulez
TheSidewinder Posted July 4, 2009 Posted July 4, 2009 Mumbles is the "CEO" here, and may decide to edit or lock this as he sees fit. I'll just say this: Mature and responsible discussion of things considered "not in the mainstream" is allowed, but once it's been pointed out that a suggested experiment is a very bad idea, the one who suggested it should take the experience of those far more knowledgeable to heart, cross it off their list of things to play with, and try something else. @Derek: "Concrete" is a mixture of sand, Portland Cement, aggregate rock and (sometimes) other additives. The variety of Concrete mixes, each one tailored to a particular specification and intended for a particular use, is staggering. The same Concrete mixture used to pour a residential driveway would fail MISERABLY if used to pour a bridge support. Did you mean "Portland Cement" when you said "Concrete"? If so, it's still a VERY bad idea, and for the reasons already mentioned: A plug of hardened cement flying god-knows-which-direction after a CATO is a bad thing. Bentonite mixes will most likely crumble during a cato. Cement mixes will most likely not. There's already enough danger in what we do. Why take those kind of chances? You have a great deal to learn, and you've started off on the wrong foot here. And to the rest of the Members: When you see someone post something you know to be dangerous or foolish, a gentle correction (with references if possible) is fine. But leave Moderation to the Staff. There is a "Report" button under the user's name. Please use it. Thank you.
TYRONEEZEKIEL Posted July 4, 2009 Posted July 4, 2009 I am a NAR certified High Power rocketeer, and I still have catos with my bottle rockets. It has everything to to do with nozzles. I mill my bentonite clay into airfloat, and ram it very hard, very little at a time. This works wonders for me, save for the few catos that happen since I dont have tooling, and I am using very rough rules of thumb to make the the nozzle geometry.
Eric70 Posted July 8, 2009 Posted July 8, 2009 (edited) Buy a cat? Joking aside, I find the cheapest to be the best in regards to material, I use Euroshopper brand kitty-litter. It should be widely available throughout Europe. The trick is to as stated by many others: Grind the kitty-litter in a blender until it's a fine powder.Add grog, I use chrushed clay flowerpots.Melt wax and pour over the pre-heated clay mix and stir well.Consolidate well with a mallet, light mallet blows and small increments work best. The method andyboy stated works well for me. My formula is based on David Sleeter's method, which I see was mentioned earlier in this long-running thread. I use Special Kitty cat litter from Walmart (red bag) and make it into a powder using a coffee grinder. After crushing a reddish-colored clay flower pot into tiny pieces, that, too, is sent through the coffee grinder. I weigh the clays and 2/3 is powdered cat litter (bentonite) and 1/3 is powdered flower pot clay. Place the clay mix in a metal pan and heat in the oven for 20 minutes at 200 F. While that is happening I melt down some paraffin wax in an old saucepan on the stovetop. After the clay has spent its time in the oven I take it out, add the melted wax and gently stir it together. Let it cool and store in an airtight container (bucket, tupperware et al). I started making core BP rockets over 3 years ago. The first 2 years I used the same method for making nozzle clay but used only the cat litter. That worked well for the 4 oz and 1 lb engines but when I started making 3 lb engines, the nozzles blew out. I started incorporating the flower pot clay in the mix and I have not had any nozzle blow-outs. Also noticed the nozzles on the 2 smaller engines do not erode as much, either. From what I understand the physical nature of flower pot clay, and grog for that matter, helps the nozzle grip to the tube so it stays in place. Edited July 8, 2009 by Eric70
derekroolz Posted July 8, 2009 Posted July 8, 2009 The method andyboy stated works well for me. My formula is based on David Sleeter's method, which I see was mentioned earlier in this long-running thread. I use Special Kitty cat litter from Walmart (red bag) and make it into a powder using a coffee grinder. After crushing a reddish-colored clay flower pot into tiny pieces, that, too, is sent through the coffee grinder. I weigh the clays and 2/3 is powdered cat litter (bentonite) and 1/3 is powdered flower pot clay. Place the clay mix in a metal pan and heat in the oven for 20 minutes at 200 F. While that is happening I melt down some paraffin wax in an old saucepan on the stovetop. After the clay has spent its time in the oven I take it out, add the melted wax and gently stir it together. Let it cool and store in an airtight container (bucket, tupperware et al). I started making core BP rockets over 3 years ago. The first 2 years I used the same method for making nozzle clay but used only the cat litter. That worked well for the 4 oz and 1 lb engines but when I started making 3 lb engines, the nozzles blew out. I started incorporating the flower pot clay in the mix and I have not had any nozzle blow-outs. Also noticed the nozzles on the 2 smaller engines do not erode as much, either. From what I understand the physical nature of flower pot clay, and grog for that matter, helps the nozzle grip to the tube so it stays in place. Also if you want extra grip for the nozzle, Try roughing up the inside of the tube with a rough file or something like that.
Swede Posted July 8, 2009 Posted July 8, 2009 Also if you want extra grip for the nozzle, Try roughing up the inside of the tube with a rough file or something like that. That's not a bad concept. A couple of seconds with a coarse drum sander mounted in a dremel would probably help significantly.
Mumbles Posted July 8, 2009 Posted July 8, 2009 Do you reduce the red clay pots to a fine powder or something of a granular consistancy? I'd get the impression of somewhat granular from the comparison to grog you make, but I just want to make sure.
derekroolz Posted July 9, 2009 Posted July 9, 2009 Mine has always been a crap, it crumbles while I drill it. Is there something that I can add to increase its strength ? Once I read an article about someone adding wax. Grind it down and pownd it down a little bit at a time.
Swede Posted July 9, 2009 Posted July 9, 2009 I solved my grog "problems" pretty much forever when I ordered about 4 kilos of Kyanite from Skylighter when I first started. I like Kyanite - it's cheap, consistent, and works well. But so would flowerpots or pretty much any fired ceramic product, with the larger chunks screened out.
Eric70 Posted July 9, 2009 Posted July 9, 2009 Do you reduce the red clay pots to a fine powder or something of a granular consistancy? I'd get the impression of somewhat granular from the comparison to grog you make, but I just want to make sure. A fine powder. I broke the pot into very small pieces with a hammer. I placed several small pieces at a time on a piece of 1/4" thick sheet of steel in a cardboard shoe box, hammered them down to almost pulverized. Took the pulverized material and powdered it in a coffee grinder. I need to change my method, hammering it down in a shoe box is rather silly but it worked. I think I will get a length of big iron pipe with threads on one end, screw a cap on it, do the same with a smaller diameter length and that should make a good pulverizer. A sidenote: The coffee grinders I use are $13 Black and Decker units from Walmart. They work great but the key to making them last is do not allow them to overheat. If I feel the grinder starting to get very hot on the sides from the motor, I let it sit for 5-10 minutes to cool - this happens 2 to 4 times in a session during the summer months. I do this work outside and the overheating is less frequent in the fall and spring when the weather is cold. Having some nozzle material of granular consistancy should certainly do the job, probably works great for some but I am weary of it prematurely wearing down the aluminum spindle. A lot of monkey work I do, probably should just order the material from Skylighter or somewhere, too, but it's fun to do it yourself.
TheSidewinder Posted July 9, 2009 Posted July 9, 2009 Eric, you *MAY* be grinding it too finely, though it should still work ok. I bought 20 lbs of commercial Grog from an Art Supply shop. It was about 40 mesh, and worked beautifully in Dave Sleeter's formula. Cost was minimal. Less than a dollar per pound, IIRC.
dagabu Posted July 10, 2009 Posted July 10, 2009 Lots of discussion here and I've been patiently waiting until all of the fighting was done before stepping in and saying my part. I have been making BP rockets for over 20 years, am a member of PGI and NLP and I still get the occasional CATO! ALL of your recipes are good, some better than others but as long as your still sending them up into the sky, well, bravo! I love Kitty Litter, I love Kaolin and Bentonite with a toilet ring baked into it, add 10-15% EZ-SLIDE graphite powder ($10.00 for a pound of it from the farm store), not the stuff for locks, its too big. It works great, CATOs before ejection but all in all, the shape of the nozzle is the most important thing. Convergance and divergance are just as important for good thrust. Dont believe me? Just look it up on Google, thaere are a bunch of public docs pertaining to nozzle design stating that the thrust can be raised 25% just by smoothing the CV & DV. Last thing and Ill get off the soap box, dont use PVC, cement or rock hard nozzles, I have plenty of friends over the past two decades get hurt, or the dog, because the shrapnell. Ill attach pictures if you want... No, not of the dog, just the nozzles. Dave
deadman Posted July 10, 2009 Posted July 10, 2009 Just a small comment. Anyone here that is interested in high horsepower vehicles can testify that gas(air) intake and exhaust can improve a great amount based on shape and "smoothness" of what they are traveling through. Hi-flow catalyctic converters cost so much more because they really do make a difference. Coned mufflers make create much less backpressure and can move air much more efficiently than standard "hole in the wall" mufflers. Rockets aren't just about the energy released but how efficiently the energy is released. Otherwise nozzles wouldn't be needed at all. Side note: I know that I know you some how dagabu. Obviously you are a going to be a great new member here, but do you post other places too?
dagabu Posted July 10, 2009 Posted July 10, 2009 Deadman, Yes, I post on a lot of topics at a lot of forums. I am a pyro and a rocketeer, I am a member of a professional fireworks group (display 1.3) and have an FAA engines and power plants certification. Thanks for the backup here, as the newby to this forum I could use a little credibility for my posts and claims. I can add some pix if anyone is interested in the crossection of the nozzle and hints for modifying tooling to do so. Dave
Eric70 Posted July 10, 2009 Posted July 10, 2009 Eric, you *MAY* be grinding it too finely, though it should still work ok. I bought 20 lbs of commercial Grog from an Art Supply shop. It was about 40 mesh, and worked beautifully in Dave Sleeter's formula. Cost was minimal. Less than a dollar per pound, IIRC. Yes, it probably is too fine for the 3 lb rockets but works and looks great for the 4 oz and 1 lb ones. I think I will give the commercial grog a try for the 3 lb rockets. I have successfully made and used over 40 1 lb rockets and 35 4 oz ones. So far I have done 10 3 lb rockets since last year, the nozzle mix I am using does work on these particular engines but half the time 30 percent of the nozzle surface is flaking or crumbling - hence the thoughts on the mix being too fine. Still works but doesn't look good. The first two 3 lb rockets I did blew the nozzle out so I slowed-down the BP and all is good. I just need to make sure I have the nozzle mix dialed-in for the 3 lb ones. Thank you for the information, I have been a lurker here and other forums for quite a while. Looks like a nice group here and I look forward to participating in some more discussions to exchange what little information I have and to learn more.
TheSidewinder Posted July 10, 2009 Posted July 10, 2009 Eric, If you're getting unacceptable nozzle erosion you could try adding a few percent of graphite to the mix. I know some folks who swear by it. Oh.... and welcome to the Forum!
50AE Posted July 10, 2009 Posted July 10, 2009 Does someone know from what Durham's Rock Hard Water Putty is made of ?
TheSidewinder Posted July 10, 2009 Posted July 10, 2009 From Google's first search result for "Durham's Rock Hard Water Putty": "Durham's Rock Hard Water Putty™ is a gypsum-based filler -- a powder -- that becomes very hard when mixed with water." That doesn't tell the whole story, and I only grabbed the first link, but it's a start. Perhaps one of our resident Chemistry Geeks can give more info.
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