Kitty Litter as nozzle mix?

[firetech]

I use kitty litter in just about all my nozzles. I grind it up a bit because I feel it packs a bit better that way. I tried adding some paraffin to my bentonite clay which is 'bulkhead mix' as referred to by ned gorski in a SL newsletter. It works OK..I haven't tried adding grog yet, maybe that will improve the performance. But for now I'll stick with kitty litter.

[fireworks]

I just purchased a tub of the Fresh Step kitty litter discussed earlier in this thread. I have been using a cheap grade of kitty litter for quite some time now, but due to many recent nozzle blowouts, I thought I'd try a better brand as suggested. Even after grinding it up in a my mortar and pestol, so far, I am not able to find much of a difference between Fresh Step and the brand I have been using. When I drill into it, it chips, and just like the cheap brand, and it feels and looks the same when compressed into a tube. What can I do to feel like I haven't wasted 10$? Edited April 14, 2009 by fireworks

[andyboy]

What can I do to feel like I haven't wasted 10$?

 

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:

 

1. Grind the kitty-litter in a blender until it's a fine powder.
   
2. Add grog, I use chrushed clay flowerpots.
   
3. Melt wax and pour over the pre-heated clay mix and stir well.
   
4. Consolidate well with a mallet, light mallet blows and small increments work best.
   

[Swede]

What am I missing here? When you consider the huge amount of work that goes into a motor and header, why not use true bentonite clay? To me, it sounds like a false economy to use kitty litter when you are trying to launch a lovingly-crafted 3" shell.

 

I understand you pay a bit more, but really, the stuff isn't that expensive. Seattle pottery sells bentonite, $16 for 100 pounds! It's already powdered. What the cat litter people do is process powdered clay and turn it clumpy, and in turn, you then have to de-clump it. Kind of a waste. Why not start with the same thing they do? No mortar and pestle.

 

I don't mean to step on any toes. If cat litter works, that's cool, but I'll stick with bentonite.

Edited April 15, 2009 by Swede

[psyco_1322]

Swede,

 

It kind of sounds like you're saying that cat litter is not bentonite, when in fact it is, and maybe more XP.

 

I have some straight bentonite, fine as dust. Its so much of a mess with all of the fluffing compared to grains of clay you get with cat litter. I would compare it to make a rocket with mill dust compared to granulated fuel. Its heaven for putting plugs in things. I think it works for people good because they can get it locally with out having to deal with traveling or ordering online and shipping costs. I don't see that the special kitty will hurt your 3" Fancy shell at all.

[Mumbles]

I think what he's trying to say is that cat litter has additives that make it more ideal for soaking up cat piss and shit. These same additives may not be ideal for rocket nozzles. I think of bentonite like any other natural product we use. It comes in a range of qualities. I've used some very good, and some very bad. Frankly, I don't know where to get either reliably, but then again I don't make many rockets either so it's kind of a non issue.

[FrankRizzo]

I use Special Kitty (Walmart house brand) mixed with a few percent graphite for all my rocket nozzles. For the price, I can almost guarantee you that Special Kitty is nothing more than just bentonite. All the Fresh Step I've seen locally has, at the very least, a perfume added to it.

[Miech]

I use plain kitty litter, and grind it up with some acetone before ramming it into a casing. Somehow the acetone clay-i-fies the kitty litter into some kind of stuff which is rammed very well and does not ever crumble. I have rather expensive kitty litter which has some wax added to it already for some reason. I assume the acetone dissolves some binders in the litter which makes it easy to process.

[Swede]

I do know that kitty litter is bentonite, and the plainer and cheaper, the more likely it is to NOT have any additives. You can also get the same thing with many of the "absorbents" sold in hardware and auto stores; they too are pretty much just clay.

 

When a hydraulic press is used, I'd guess that it'll crush litter nicely, and you'll get a great nozzle, but if you are using a mallet, a more elaborate clay+grog+wax mix just might hold together better.

 

My point was only that some guys are forced to grind kitty litter to get it to a consistency they like, when it can be purchased as the powder for not too much $$. When the wax and grog are added and so-called "nozzle mix" is created, the wax keeps it dust-free, and it handles nicely. The wax also inhibits moisture from entering the nozzle and causing it to crack or shrink.

 

But I have no doubt guys are doing well with cat litter and don't want to discourage something that works. Some time ago, I bought the Sleeter book "Amateur Rocket Motor Construction" and pretty much followed his recipe. I remain very impressed with his book. The guy worked his ass off on serious BP motors and knows his stuff, so I figured his nozzle recipe would work well.

Edited April 18, 2009 by Swede

[TrueBluePyro]

What am I missing here? When you consider the huge amount of work that goes into a motor and header, why not use true bentonite clay? To me, it sounds like a false economy to use kitty litter when you are trying to launch a lovingly-crafted 3" shell.

 

I understand you pay a bit more, but really, the stuff isn't that expensive. Seattle pottery sells bentonite, $16 for 100 pounds! It's already powdered. What the cat litter people do is process powdered clay and turn it clumpy, and in turn, you then have to de-clump it. Kind of a waste. Why not start with the same thing they do? No mortar and pestle.

 

I don't mean to step on any toes. If cat litter works, that's cool, but I'll stick with bentonite.

 

That is why I buy the cheapest of the cheapest brands and it works great for my little rockets and up to my 8oz rockets, cause the cheaper stuff is near, pure with nothing added

 

"Content of kitty litter"

- bentonite clay

 

plus if you are in australia there are a few bentonite clay mines around. I drive past one when I go home and the same with a coal mine and I tried coal, but it didnt work for BP, lol (back in the good ol' days, I know better now )

[Yankie]

I use home brand kitty litter, put it in the blender for a while and use whatever passes a 20 mesh screen. It is good as some is fine powder, and the rest is small granules, I beleive these small granules in a way act similar to grog, maybe not as efficently but better than nothing.

[Swede]

How about graphite?

 

I know hard graphite is machined into killer nozzles, but can anyone think of a use for powdered graphite as an additive or adjunct to clay nozzles? Or would this be a case of tampering with something that already works? I'm trying to come up with uses for nearly 10 pounds of powdered graphite that I picked up a while back. All I do with it now is add a touch to BP to give it that cool shiny look.

[Mumbles]

Graphite is a fairly common nozzle additive. It's reported to give better anti-corrosion(heat wise) properties, as well as improve release from tooling.

[tentacles]

Definitely add a few percent to your nozzle mix! It really helps with releasing the tooling. FrankRizzo and I don't even bother to measure it, just add some graphite and mix it in with the clay, it'll have a sort of medium grey color. I've tried adding lots and it is definitely possible to add too much, but you can sort it out with more clay.

[Ventsi]

But if one isn't using tooling the graphite is almost useless.. yes?

The only purpose I can see for it smooth gas flow trough the nozzle and reduce erosion??

[Mumbles]

It could help reduce chipping and flaking by drilling the nozzle out, as well as helping with errosion and all that.

[hondo]

durhams rock hard water putty, mist with water to dampen just a little and press, that stuff sets up like concrete, more expensive than kitty litter but never had a blow out for what its worth

[TheSidewinder]

You're not the only one I've heard suggest that.

 

One or more members of the WPAG have used that method before, and with 100% success like you've had.

 

But like you said, it's expensive if you're doing a lot of them.

[hondo]

4 pounds of durhams rock hard water puddy is about 5 dollars US, so its not so expensive considering the nozzel erosion of clay and loss of thrust and blow outs. and you dont have to use is for the top plug, Cheap isnt always better, I have seen nozzel erosion on my clay nozzels to be 2 times the original hole size ,,,,, and very little to no erosion(ie no increased in nozzel opening) on durhams water putty, I try to be very consistant, same pressing psi on the nozzels and same weight iin grams of clay vs the durhams water putty, about 15 grams for the nozzel is my standard, the rockets I make are 3/4 ID, 1 pounders? the way I figure it its 0.04 cents per rocket, now thats inexpensive and if you mix up too much rock hard water putty, when it dries you just grind it up and use it again. try some, the only down side is they need a few days for the nozzels to got get really hard. I took pics but you cant really see anything different but when you scratch the nozzel with you finger nail if feels and sounds like ceramic. I also use rock hard putty for the end plugs for my turbillions, never had a plug blow out but have had the tubes split

[derekroolz]

i personally recomend using concrete it is about the same weight but u dont have to use as much space because it is a wuite deal bit stronger i also put a end cap on the rocket that is sealed it gives you tons of more room for fuel but can become a missle some times so dont launch it in a neighboorhood

[Mumbles]

You know, you're starting to tread on thin water with these unsafe suggestions. Clay and durhams will shatter in event of a CATO, but cement will likely stay together and provide projectile hazards.

[derekroolz]

You know, you're starting to tread on thin water with these unsafe suggestions. Clay and durhams will shatter in event of a CATO, but cement will likely stay together and provide projectile hazards.

 

 

If the person is being stupid enough to not creat a proper rocket, They obviousily dont know what the hell there doing.

[homebrewed77]

If the person is being stupid enough to not creat a proper rocket, They obviousily dont know what the hell there doing.

 

 

You do know even the best rocket guy's there are, still get cato's quite often. Hell I bet the first 15-20 I built became ground salute's, untill one flew..But im far from a pro. May i ask you how long you have been building rocket's?

[derekroolz]

You do know even the best rocket guy's there are, still get cato's quite often. Hell I bet the first 15-20 I built became ground salute's, untill one flew..But im far from a pro. May i ask you how long you have been building rocket's?

 

 

For about the past 2 years and never once have i had a cato. And that is the bare truth, believe it or not

[Mumbles]

Something about you makes me question that you've been making anything for 2 years.