derekroolz Posted July 22, 2009 Posted July 22, 2009 So I had a little trouble with my rockets being too powerful(not to brag) And my nozzles end up getting blown off a few secounds into flight(i have tried all sorts of diameters for my nozzles but they still do the same thing)So I was wondering how to make grog as kitty litter proves to fail even when grounded down to a powder...so were to start with grog mix....as some might expect concrete is dangerous! Got any ideas!
Mumbles Posted July 22, 2009 Posted July 22, 2009 Grog can be made by smashing up ceramic tiles, and screening it to get an appropriate mesh. You might also want to try compressing it more. Are you using cardboard tubes, or something else?
derekroolz Posted July 22, 2009 Author Posted July 22, 2009 Grog can be made by smashing up ceramic tiles, and screening it to get an appropriate mesh. You might also want to try compressing it more. Are you using cardboard tubes, or something else? Well one time I tried copying an estes egine and I can make the tubes....Just not the plug mix,but when I look at the proffessional ones they use heavily compressed Grog. and I am trying to figure out how to make it.
andyboy Posted July 22, 2009 Posted July 22, 2009 Well one time I tried copying an estes egine and I can make the tubes....Just not the plug mix,but when I look at the proffessional ones they use heavily compressed Grog. and I am trying to figure out how to make it. He just told you how to make grog in the previous post, smash up a clay-pot and collect the grog. Mix that with ground up kitty-litter and off you go. Be sure that the nozzle bulges out in the tube a bit, then you are sure that it will stay in place. http://en.wikipedia.org/wiki/Grog_%28clay%29
Eric70 Posted August 11, 2009 Posted August 11, 2009 Or try adding more charcoal to your fuel. The fuel *might* be too fast and is blowing out your nozzle. I had that problem with the 3 lb BP rockets, the next batch of powder I made, I reduced my KNO3 by 1 oz and it worked fine.
PyroMan16 Posted August 18, 2009 Posted August 18, 2009 Kyanite added to bentonite also strenghtens it a bit. Also, use paper tubes and pound it till it expanded a little bit to better the grip between the paper and plug
WSM Posted August 22, 2009 Posted August 22, 2009 So I had a little trouble with my rockets being too powerful(not to brag) And my nozzles end up getting blown off a few secounds into flight(i have tried all sorts of diameters for my nozzles but they still do the same thing)So I was wondering how to make grog as kitty litter proves to fail even when grounded down to a powder...so were to start with grog mix....as some might expect concrete is dangerous! Got any ideas! I see two problems; 1) The nozzles blow out and 2) The propellant may be too powerful for the system. I would try adding a plastic ammendment. Try adding either paraffin or boiled linseed oil to the nozzle mix. When the nozzle mix comes under pressure during consolidation these ammendments go "plastic" meaning they get fluid and flow around the hard grains of the nozzle material and into the fibers of the engine tube, "locking" them all together plus helping prevent errosion during the burn. As others have mentioned, toning down the mix is an option. Possibly a compromise between the two; slow the mix a bit AND strengthen the nozzle mix and see how it works. Do you have any detail questions? This group is willing to step up and contribute helpful ideas and suggestions. We love to help each other succeed.
maximusg Posted August 23, 2009 Posted August 23, 2009 Yes, working on optimizing the composition is also an option, add more charcoal for slower burn and larger tail effect etc... Various meshes of grog can also be obtained from ceramic supply stores. It's very cheap for the few kilos that will last you a life time.
derekroolz Posted August 24, 2009 Author Posted August 24, 2009 Yes, working on optimizing the composition is also an option, add more charcoal for slower burn and larger tail effect etc... Various meshes of grog can also be obtained from ceramic supply stores. It's very cheap for the few kilos that will last you a life time. yeah i am not able to find any grog at any stores
Eric70 Posted August 24, 2009 Posted August 24, 2009 yeah i am not able to find any grog at any stores Find one of those reddish-colored clay flowerpots and smash it into little pieces. Screen it out and you have your grog.
PyroMan16 Posted August 26, 2009 Posted August 26, 2009 Sand is a good substitute for grog. Just little amounts thou.
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