pycharm Posted April 1, 2021 Posted April 1, 2021 I remember reading about nozzle mixes made from bentonite and another chemical that was described as adding some "bite" by grabbing the inside of the tube. Some kind of chem thats relatively coarse. Unfortunately I can't remember the name of it. Does anyone else know what I'm talking about? Oinikis, you got there first hahahaI believe you're talking about mixing in grog with the bentonite. I've read it helps to grab the tube.
MadMat Posted April 1, 2021 Posted April 1, 2021 (edited) Ok so i cant get my rockets to fly, they almost always cato! I havnt tried nozelless, but im hoping it will help, then as i get more experience start to make nozzel, does this sound like a good plan? Any help would be great, we cant buy pyrotecnics where i come from! Not any at all, but i can get the stuff to make them so easily! It doent make sence, more likly to hurt yourSelf or someone else making your own! Not that it would change my desire to make my own just saying! Does anyone know if it is hard to make bumble bees yourself?There are a number of reasons for constant cato's. I need to know a few more things about your rockets before I can give you any advice. Are you making black powder or Rcandy rockets? Do your rocket have a core? One cause of catos common for beginners is making the nozzle throat too small. A good starting spot is approximately 1/3 the inner diameter of the rocket tube Other than that I need more information Edited April 2, 2021 by MadMat
MadMat Posted April 1, 2021 Posted April 1, 2021 One thing to keep in mind about the nozzle plug. It must not end flush with the end of the tube. When pressing my nozzle plugs I have a spacer that is about 1/4 inch (6mm) thick in the end of the tube. When you press the nozzle plug there should be enough pressure to expand the tube slightly. The extra 6mm of tube at the end (not expanded) acts to hold the nozzle plug in place. 1
justvisiting Posted April 1, 2021 Posted April 1, 2021 MadMat, yes, that's really important! A while back when NEPT tubes were unobtanium, a guy was stacking washers to eliminate that 6mm (or most of it), I think to squeeze 4 BP motors out of 1 tube. Anyhow, I thought it would be OK with nozzleless. It isn't. That little extra bit also keeps the tube from opening like a zipper when the tube support is removed. Found that out the brown pants way
sabidao Posted April 26, 2021 Posted April 26, 2021 you can continue using kitty litter, if you scratched into the barrel with coarse sandpaper will help the nozzle to not blow up
vendrite Posted May 5, 2021 Posted May 5, 2021 The ole rocket master, AKA Steve LaDuke uses crushed clay flower pots and bentonite clay, cat litter. 50/50 by volume. Works great with proper pressure, 9000# on the nozzle.
Uarbor Posted May 18, 2021 Posted May 18, 2021 (edited) In my futile search for a clay pot to break up for grog I came across some old clay pigeons. They were pretty easy to break up and incorporate into the kitty litter. I also added an unmeasured amount of candle wax. Mixed it all in an old blender it was a perfect success so far Edited May 19, 2021 by Uarbor
MadMat Posted May 21, 2021 Posted May 21, 2021 (edited) One thing to consider when using clay pigeons. Some of them aren't actually clay but rather some type of phenolic plastic. Unless you're making rather large diameter rockets, you don't really need grog. I have made a LOT of rockets in the range of 3/4" to 1" I.D. and have never used anything but kitty litter for the nozzle plug. Sure my nozzles probably erode, but my rockets are one shot lifters for a header, so I don't care. A nozzle plug, properly pressed (or rammed) and inset about 1/4" into the tube will work without problems. Of course you also need a decent quality tube (To quote an old saying: I roll my own) Edited May 21, 2021 by MadMat
Uarbor Posted May 22, 2021 Posted May 22, 2021 One thing to consider when using clay pigeons. Some of them aren't actually clay but rather some type of phenolic plastic. Unless you're making rather large diameter rockets, you don't really need grog. I have made a LOT of rockets in the range of 3/4" to 1" I.D. and have never used anything but kitty litter for the nozzle plug. Sure my nozzles probably erode, but my rockets are one shot lifters for a header, so I don't care. A nozzle plug, properly pressed (or rammed) and inset about 1/4" into the tube will work without problems. Of course you also need a decent quality tube (To quote an old saying: I roll my own)Rolling my own tubes is a pretty attractive idea. Considering I have been paying a dollar each by the time you include shipping.
ronmoper76 Posted May 30, 2021 Posted May 30, 2021 I'm a bit of a cave man i suppose but i dump the kitty litter from the box right in a blender and use from there......It doesn't even burn through with fountains,actually it gets harder from what i can see. I bought bentonite and used it before,but i noticed zero difference and went back to cat litter quickly. It's all i use,lol
vendrite Posted November 26, 2021 Posted November 26, 2021 The "rocket master" crushes clay flower pots to pass thru window screen and then mixes volume to volume with bentonite clay. 50/50 volume. Never had one blow out, holds up very well. It doesn't get much cheaper of easier than this. I miss Steve LaDuke.
Carbon796 Posted November 26, 2021 Posted November 26, 2021 " I miss Steve LaDuke " Did he pass away last year or something ?
justvisiting Posted November 26, 2021 Posted November 26, 2021 Steve Laduke is still around. I PMed with him on another site (Ned's) a couple of months ago. He's tired and getting on in years- but he's still kicking! I'm pretty sure he also uses wax in his flowerpot/ bentonite nozzle mix.
Carbon796 Posted November 26, 2021 Posted November 26, 2021 That was kinda my thoughts also. But, I haven't been on FW'ing recently. Thanks for confirming, that he's still alive and kicking.
markx Posted December 27, 2021 Posted December 27, 2021 Adding a tab of appropriately diluted sodium silicate solution (waterglass) before pressing the bentonite granules shall also do wonders for turning the mass into a monolithic composite and also gluing it in place.
Pyroboy Posted January 3, 2022 Posted January 3, 2022 I recently got issues with plain bentonite nozzles. Well I know it shrinks or expands with different humidity, because the main silicate is Montmorillonite, but till now I never had problems. Maybe because I did not store my rockets long enough. Anyway, I want to change the nozzle mix to get better storage stability and came up with some questions. I hope maybe some can help .Did some of you tried paraffin oil instead of solid paraffin? Or is there any disadvantage? Skylighter uses solid paraffin and needs to heat it. With oil it would make the heating obsolete.And what about other silicates like kaolinite, that does not tend to shrink or expand that much. Have anoyone tried plain kaolinite or mixtures of diffenrent clays? Thanks a lot an happy new year .
mabuse00 Posted January 3, 2022 Posted January 3, 2022 Using plain bentonite once delivered from a pyro dealer I found that apart from the swelling issue it is unsuitable because it erodes badly. The solution so far is the skylighter formula:paraffine wax 8bentonite 61chamotte 31Though I prefer to use rather 10% wax, and I'll try to raise that in future. More wax -> less dust, better granulation... until erosion kicks in again, but I'll have to find out where that point comes. With 10% there is very little erosion and the nozzles are at least to some point water resistant. NYE was a permanent drizzle here, as if you walked in a cloud... No real rain, but 5min outdoors and you where completely wet. It did not bother my EBs at all. With oil it would make the heating obsolete.If it stays where it should and does not migrate someplace else... The wax procedure isn't that bad, just make a big batch and you're done for the next years... plain kaoliniteI tried a 90/10 mixture with 64°C MP paraffine wax.I cannot comment on shrinkage/expansion, but apart from a lower bulk density (what makes it a little less pleasant to work with) - it erodes just like plain bentonite. Additional chamotte is needed. Chamotte must (imho) be a fine powder. I got mine from a pottery shop. The coarse stuff that is recommended sometimes might "grab the tube" but also grab and scratch the poor spindles... I had no blowouts even with whistle mix in endburners, using waxed tubes and very tight nozzles. PS:And please do not start the usual cat litter discussion. It's different around the world. All thew stuff i tried was unsuitable, some contained sand and bigger rocks - no thanks... 1
Pyroboy Posted January 4, 2022 Posted January 4, 2022 If it stays where it should and does not migrate someplace else...Good point. I don´t know how fast the diffusion of paraffin oil within comps or paper is. It might be faster with low viscosity oil, so I better try high viscosity ones. But I think I´ll give it a try! PS:And please do not start the usual cat litter discussion. It's different around the world. All thew stuff i tried was unsuitable, some contained sand and bigger rocks - no thanks...Haha don´t worry. Kitty litter is a lot more expensive than buying plain bentonit (granular or powder) from pottery or specialised shops . Thank for the advice with the chamotte powder. I really didn´t know that there is powder available on the market. I will get some of that and try it instead of granular one. What also would be interesting is Potassium-Bentonite. What I read it doesn´t shrink, but I would say that without the crystall-water the cohesion is less and it won´t give fine nozzles. I tried Calcium-Bentonite once and that one isn´t as suitable as the sodium one.
mabuse00 Posted January 8, 2022 Posted January 8, 2022 The problem with my bentonite is - I dont even know what it is Sodium (most probably), potassium, calcium? Who nows.That's why I hate to work with stuff that's not specified. Years of experience, but all results are based on blurry premises. What also would be interesting is Potassium-Bentonite. What I read it doesn´t shrinkThat needs to be tried sometime... I dont want to rule out kaoline. I just had the hope that it would serve me plain, without fireproofing additives, what it clearly does not.Swelling-wise, it might have some advantages. Also one could question for how long oiling or waxing the mix prevents water exchange. I can imagine the water to permeate through the oily/waxy mix over time and still cause problems - the question is how long that takes in practice.
justvisiting Posted January 8, 2022 Posted January 8, 2022 (edited) Estes rocket engines have bentonite nozzles, pressed from- you guessed it- cat litter. They use Dr. Elseys Precious Cat Litter. It was the former manager of Estes Corp. that suggested its use to the pyro community. Estes motors can be stored for a decade or more and function like the day they were made. Many of us copy their success. Some folks swear by cat litter, some folks say it's all no good. The truth is somewhere in between. Some litter is too hard and dense, some is too soft and fluffy. Sometimes a mixture of both types gives excellent compaction and still provides good 'bite' on the tube. Lots of folks employ wax in their nozzle mixtures, although I've never read of anybody feeling the need to add any to Dr. Elseys. If rocket engines are to be stored in conditions that allow for moisture to be absorbed by the nozzle, that same moisture is also affecting the tube and the propellant grain to some degree. Estes motors are sold all over the world, and stored under varying conditions- as mine have been- and remain unchanged. I think the reason is because they consolidate the propellant grain to maximum density (by using water), and use Dr. Elseys nozzles, which are also consolidated very well. I think many of our failures of rocket engines that are stored for lengthy periods come from our failure to achieve Estes densities. I have used Estes D-12 engines that are over 20 years old. EDIT: I use 1 teaspoon of fine graphite powder per cup of Dr. Elseys litter to help release the nozzle from the spindle with greater ease and less residue on the spindle. Edited January 8, 2022 by justvisiting
Bourbon Posted January 8, 2022 Posted January 8, 2022 I use use Dr. Elsey's, straight from the bag form. I just did an experiment about four months ago. I "hand rammed" two 1# nozzled core motors. I intentionally did a no-no and set them in my kitchen; open to the elements right behind my sink faucet. I left them there for 3 months to observe nozzle and grain deterioration, with the harsh changing environment. Hot, cold, moist, cleaning around and moving. The motors held up almost perfectly. I say almost, because I couldn't tell any difference, but I'm sure there was some effect, (has to be.) However, I took them out and flew them. Fantastic flights... 240 gram dummy load on each one. Definitely not a scientific experiment, but good enough to see if the nozzle was going to crumble, shrink, swell or whatever... I should have weighed them before and after, though!
mabuse00 Posted January 8, 2022 Posted January 8, 2022 Dr. Elsey'sYeah that's all very nice, but Europeans cannot buy it - end of story. Its irrelevant for us.Also - if this works so wonderful, what is it? What are the ingredients? I don't like such mystery materials...
justvisiting Posted January 9, 2022 Posted January 9, 2022 (edited) mabuse00, the MSDS lists the "mystery materials" in the product you've deemed irrelevant. I'm sure that the same or similar mystery materials are available in Europe. Meanwhile, the information about Dr. Elseys may be helpful to the majority here that are not in Europe. I shared it for the benefit of the group, and I'm sorry if you failed to see value in it. Can't please everybody https://www.amazon.de/Precious-Clumping-Natural-Allergenic-Litter/dp/B0009X0QSY/ref=sr_1_26?__mk_de_DE=%C3%85M%C3%85%C5%BD%C3%95%C3%91&crid=1TK1KAO56P7N5&keywords=dr+elseys+cat+litter&qid=1641755300&sprefix=dr+elseys+cat+litter%2Caps%2C168&sr=8-26 Edited January 9, 2022 by justvisiting
mabuse00 Posted January 10, 2022 Posted January 10, 2022 (edited) I never found an MSDS for that stuff - am I blind?But someplace else they claim:Premium scoopables, like ours use 100% sodium bentoniteThat seems to apply for the variant you posted.Really just bentonite? Assuming theres nothing else - then what makes this stuff work so good?Maybe it's some special processing?Why does it not erode? Greater density? Dr. Elseys nozzles, which are also consolidated very wellExtremely well... Could it be that the stuff is somehow "pre-densified"? Maybe I have to make some trials with varying pressing forces. As an arbor press user I have my limits though... Edited January 10, 2022 by mabuse00
Bourbon Posted January 10, 2022 Posted January 10, 2022 Sodium bentonite: has strong absorbency and propensity to clumping, which leads to it being used as sealants, liner for toxic waste lagoons and deserted oil and water wells. It is also used in drilling, clumping and bonding agents for cosmetics, cat litter, and medicines. To my understanding, not all cat litters are the same. Most having mixtures of clay and several fillers (like anti-clumping.) I use mine straight out of the bag. Others like to powder it and add other goodies. I like the mesh size right from the bag, I think it gives bite to the tube and consolidates nicely. That being said, I only hand ram... But sure looks like I pressed it... I could only imagine the great stuff a press does on it by comments from others. When people mention Dr. Elsey's, they're going by that particular brand because of Elsey's attention to detail and standards (no other crap in there) or, yet lol. They guarantee their litter is sodium bentonite. I'm sure there are many other brands. I don't know that sodium bentonite is the holy grail, but it is tried and true. Been used in the motor industry since the beginning.
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