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1lb Rockets Failing - I Need Help


joeyz

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Great progress, we've got another one over to the dark side :) Regarding the waxing, you don't dip the tubes. You coat the inside only. Here's a reference on that. http://www.pyrobin.com/files/Reducing%20Catos%20in%20Pyrotechnic%20rockets-V2_1.pdf

Enjoy your new toys!

A cheap option for a tube support that you make yourself:

http://www.pyrobin.com/files/Tube%20support%20for%203lb%20strobe%20rocket%2C%20made%20for%2020%20bucks_1.wmv

I've made a few of them. It's not that hard. Here's a link to a picture of them. The picture is huge when I try to post it here!

http://www.pyrobin.com/files/brass%20tube%20supports%20022.JPG

Edited by DavidF
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Team, here is the concept i am going to build to make it a more efficient process. My hydraulics pneumatics guy recommend to use pneumatic. the dial panel i can make with sheet metal so i can add labels etc. Here is a draft i came up with, its only a draft...

 

SEE PICTURE

 

Ready for you guys to beat me up lol

 

now i need to find a tecnical chart table on different size rocket pressure to press.

 

post-20673-0-00272900-1471641700_thumb.jpg

 

if gun reloaders can have a hopper, so can we.

 

post-20673-0-28546800-1471642896_thumb.jpg

Edited by joeyz
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Weird. Today i got in my 10k rocket press pressure guage and its filled with clear hydraulic fluid in the glass area like a bubble level. Put some pressure on the pressure plate and it doesnt move. Concluded that its either defective or the fluid is a shipping/storage fluid and needs removed. Any i dea on this? I emailed caleb from woody for guidance.

 

Also got phil's tubes in today. Definately better tubes than what i had and cant wait to try it.

Edited by joeyz
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Do not empty the fluid. It is a glycerin filled gauge, the fluid is there to prevent fluttering of the needle. This can happen on hydraulic pumps. If the gauge does not move it could have a blockage in the snubber. Call Caleb if that is where you got it from. Your one ton press may not budge a 10000 psi gauge. If you have the dimensions of the piston, the gauge reading can be calculated.
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Thanks OM ,so if it is 1" dia and you apply 2000lbs of force the gauge reading should be 2,547.7psi. This should still show up on a 10,000 psi gauge. I'm wondering if it may need filled with hydraulic fluid or has an air bubble? It could be bottomed out before it reads any pressure.
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If I take my 10000# PtoF gauge and crank the handle on my 1 ton arbor press, I can move the needle. Not a whole lot, but it does move.

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It's a 1 square inch piston on the gauge. So if you put 1000 lbs on the gauge it will read 1000 psi

Who knows why it won't move.. I emailed ya right back this afternoon. I check them all when I build them but that doesn't mean something silly hasn't happened or that gauge is just slow to get off the bottom. I check them at whatever pressure my press is set at the time. stack them all up. push on them and see that they all read the same. bam. done. or.. thought i was done. :)

We will get you fixed up in short order.

Sorry for the trouble for sure.

Caleb

 

 

Now that i see all you are using is an arbor press I think I shoulda sent you a 6000psi gauge with no fluid in it. :(
I can fix that. :)

Edited by calebkessinger
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Cal, if you recall I got the arbor Ned built for the write up. I think I got a 4K P2F from Wolter Since it's a 1 ton press and I find it difficult at best to even get near maxing it out as the press is set up. A cheater pipe would make that easier, but I'd fear damaging the press trying to do that. It's trying to walk away when I'm dogging on it around 2k. That 10k gauge should wiggle a little, but it's gonna be very little I would suspect.

 

Joey, if I've missed it can ya show a picture of your press. You may have a simple problem of not enough force from lack of leverage in my lowly non rocket building opinion. Couldn't poor consolidation give a chuff effect and possibility of rapid burn from the original posts? The Dave's and Cal have way way more knowledge and experiance than myself though. I'll retract to the shadows now and Cal can call and tell me I'm crazy or to shut the beep up if I'm way off base, lol.

Edited by Boophoenix
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team, thanks for the clarification on fluid. Caleb is going to send another. Caleb does great service and i love his tools so far. better than the cheapo end burner for sure. just a little bad luck on gauge. yes, i do clamp it down, same as being bolted. i know im getting at least 2,000 on it cause i pressed at least 30 rockets and clay nozzles hasnt failed me yet. i havent had to use the arm extender yet. tis one of the reasons why i contacted caleb to purchase a pressure gauge, would like to exactly see what im pressing and keep each press exact.

 

boop, here is the picture of the ned gorski setup, up to 2lb motors, according to his vids. this 1 ton is temporary until i make my pneumatic press. any tip on it? should i reduce the height?

 

NOTE: i moved the press to the top of my freezer so the table has white background for photo purpose. i do clamp it down on my wooden work table.

 

 

post-20673-0-01127100-1471835646_thumb.jpg

Edited by joeyz
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Damn! That's a pretty little press! I see a HF ratchet with extendable handle on there as well.
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I see a big torque wrench on it. Then put the gauge away. Waaaaay faster :) Nice to see a new pyro gittin' 'er done right off the hop though, I have to say :)

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thanks guys, i owe it to you all for coaching me in the right direction. i have learned a lot.

 

- extendable rachet handle: yeah, rachet wrench handle just in case i need to press something harder, habor freights $10.

 

- gauge: main reason why i wanted the gauge to ensure each press is exactly the same pressure.

 

quick question on pressing the clay nozzle... how thick is the clay plug suppose to be for 1lb end burner and how thick should it be for 1lb core burner? i might be pressing too much clay, deep throat clay nozzle. i saw conflicting videos on youtube on clay nozzle thickness, ranging from 1/2" to 1" and still researching correct nozzle size for end and core 1lb burners. by reading others here in forum, it appears many dont use a clay nozzle. maybe i shouldnt use clay nozzle and wont have to worry about it. but i thought the clay nozzles, like estes rocket engines, need it produce thrust? also, on core burners, do you just fuse the tip or fuse to the top of inside hollow core or would that cause a cato? lol

 

i got a bunch of phil's 1lb tubes in, cant wait to wax inside walls and press with the new bp fuel i made for the end burner. i made a new batch you guys recommended for end burner 75/15/10. and use the other bp 70/20/10 batch on 1lb core burner. i need my rockets dependable to push 3" ball shell, as a licensed professional, i have cases of these for when i dont have time to construct my own headers from scratch which i love doing too. i only use rockets (or anything i make) for personal hobby. i never use homemade stuff in any public display. i strictly use factory mortars, cakes and special effects (comets, mines, meteors, fountains, strobes, gerbs, wheels etc) in displays. public safety always comes first and i dont trust or allow any commercial 1.3g rockets of any type in show and are not in my inventory lol

 

i like these tubes from phil so far...stronger, harder but smooth as a baby's butt. i now fully understand when you dave and dag said that tubes matter. i also guess you guys use the wax is to take care of the internal spirals, fill in the gaps to prevent schuffer, putt putt sound and more even burn and minimize spark creep pass fire along inner wall. it would be nice to find these tubes just one more tick mark below 1/8" wall thickness.

Edited by joeyz
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Joey, I haven't clamped mine for use yet. I do use the handle on the ratchet extended though. This may be from my poor location of use and not being clamped, but if I understand your post earlier you're not extending the handle?

 

My P2F is in a box somewhere about from an adventure to Patrick's a while back. If the above questions answer is yes I'm gonna guess you're not getting enough force to really load a 10k gauge unless you're really doggin down in the short handle? I'm pretty sure mine is a 4K I know it's on the low side as I got it specifically for the arbor press. I'll dig it out tonight and check my statements, but I pretty sure I'm recalling correctly from my experiances.

 

Take that vairible and I don't recall ( fixing to head to work so have to be lazy and not reread ) if I read anything about incriments sizes as you build and we may be on to something maybe? ( kind of a question for the more experianced guys so I'll know if I should Shup )

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The length of the clay nozzle may very between manufacturers. The only way to ensure how long the nozzle needs to be is to put a mark on the spindle at 2x the dia, slide the nozzle former on to that mark and lay out the top of tube mark on the rammer. When you fill the tube with clay the first time count the number of scoops it takes for a compressed nozzle. I mark that number and scoop size on the bottom of the spindle base so I don't forget.

It is not necessary to make a core in the motor. Most end burners will sit on the launcher for a second until it builds up enough surface area and pressure. If extra thrust is desired during lift off it would be necessary to use a drill bit after the tooling is removed to ad a 1/4" core.

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boop, im pretty sure im getting 2k to 4k with that press and i dont use the handle extender for more leverage. when i do use the handle extension i wind up doing too much pressure, i can warp or bubble the side of the tube or crack the case. as for the gauge, i know it goes to 10k but i never will produce that amount on this small press but it should at least register 1-2k as i press what i got. like caleb said, it can be useful for all rockets. im thinking its just a calibration issue or maybe it has a clog and my press isnt strong enough to unblock it which is why its stuck on zero. not sure whats up with the gauge but caleb is sending me another, 5k. hes a pretty reliable professional. like dag said, hes fast reacting and cares about his customers. i am eyeing other tools to buy from him as soon as i can afford it. rocket tools stuff is expensive stuff but chems is reasonable which keeps me hobbying.

 

neighborJ, excellent tip, i forgot about the logical pass line markings on the rammer. i thought it was just a generic marking on the end burner tool. so i guess i need to measure from that line to the flat base that the spindle is attached and that determines the length of the tube i should be cutting. when i see that line flush on the top of the tube. part of my trouble might of been using precut tubes 3 1/2" on a 5 1/2" end burner tool and guesstamating stop point. even when i mark a line, im still off for some reason. could also be why i dented my spindle a few times too. i think i got it now, phils tubes are long and i can now cut to length, i should do much better now with accuracy/precision. i guess once i get better experience and practice then i can do better on shorter tube measure a new stop point line.

 

as for core burners, do you guys stuff the fuse all the way up the core or just enough to touch bp fuel. i saw some conflicting comments about that in other threads. someone says to feed it all the way in and others say dont, it will explode and others say you need to ignite the entire core for more burn thrust. IDK, i guess i can build two and test both ways and measure performance for meself, lol

 

i cant wait to get this rocket stuff all in fine tune cause i got cases of these new pixie dust blue, gold and silver shells that we use at six flags, sea world and disney. simply remove the lift cup, quick match, clip the fuse shorter and you got a nice header. i shot like 100 of them included in the finale during several 4th of july shows and the crowds where roaring in excitement. people were calling them tinkerbell shells. beautiful shells in disney theme pyro musicals lol they are kinda over powered for 3", the pixie dust burns long time all the way to the ground and i have to have fire team always standing by. they really should be higher in altitude like a 4" or 5" shell, more lift charge. a rocket would definately get it up there allowing more time to burn down safely. will make a couple of vids, very pretty shells. another shell i cant wait to test on a rocket is my custom dallas cowboy 3d shells, beautiful blue, white, blue layer dallas cowboy star logos in the sky. once i finish final improvements, sending specs off to our manuafactorer in china to mass produce so we can use at dalls cowboy stadium. cowboy crowds is going to shit their pants when i fire 50 of these and fill the sky with their logo. sl if you see this on tv in future super bowls, you know whos behind it lol ;)

Edited by joeyz
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Looks we have the typical 11 answers issue with a rocket question.

 

Coreburners:

 

Nozzles from clay: The actual nozzle depth is irrelevant in that the convergence (converging all the gasses together to go through the throat) and divergence (allowing laminar flow to smooth out and maximize thrust) are part of the 'nozzle' clay are cannot be changed.

 

The part of the nozzle you have to be concerned about is the throat. That is the narrowest portion of the nozzle where the gasses reach supersonic speeds. The throat needs a few commonalities to be successful and are considered to be universal. The length of the throat should no be too long, 1/2 ID is plenty. A longer throat can cause serious chuffing, sputtering and CATO. All that gas needs to go somewhere and if you have any kind of tail on the motor, that tail material has to be expelled out of the motor via the nozzle.

 

Second, the throat has to be cylindrical and not tapered. If the throat is too long, the spindle causes the throat to take on the taper of the spindle. The tooling manufactures leave a portion of the spindle with no or little taper for that purpose.

 

This is a drawing done of a washer style nozzle, think of the green line as the throat, you will want that distance (here it is the thickness of a washer) to be about 1/2 the ID of the rocket motor and cylindrical.

 

gallery_9798_35_6965.jpg

Edited by dagabu
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omg dag! your a hero! that really clarifies it and rests my worried mind. now i better understand clearly. my washer line was about 1/8" to 1/4" inch thick, deep throat clay gap between divergent and covergent and should be thinner according to your diagram. you should be a pyro rocket professor at a university ;)

 

PS. sorry for so many questions, didnt mean to get carried away, i am a multi task person with too much energy and love pyro lol

Edited by joeyz
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Endburners:

 

The nozzle on the endburner also has a convergence and divergence but they do not have to be so pronounced as the biggest issue you will likely have is tube burn through right where the convergence meets the tube. This can be minimized somewhat by asking your tooling person to turn a skirt on the end of your first rammer but this also makes that rammer only good for the nozzle and not for any BP.

 

Endburning rockets use a spindle as well but it is often called a nipple or tit since it is very short, about X2 the length of the actual nozzle throat. More than that and the rocket can cause a high pressure spike at ignition causing the casing to blow out.

 

Like the coreburning rocket, the throat does not need to be very long, about 1/2 the rocket ID is as long as you want and a throat 1/4 the ID is much more suitable especially when metals, charcoal or other materials are present for giving it a tail.

 

Hopefully, your tooling maker does not taper the tit too much, if they do, you will have to open it slightly. That brings us to a rather universal issue with clay nozzles.

 

Shrinkage!

 

Exhaustive tests by amateurs have been performed on clay nozzles, much of the time this is due to blowouts of the nozzle or casing failures (CATO). This, in turn led to a lot of mixing different clays and adding wax or some other phlegmatizer to the mix to help bind it. Why all this trouble?

 

Nozzle throats shrink.... A common site with competition rockets is a rocketeer using a drill bit and slowly reaming out the nozzle bore by hand. We all know what Bentonite Clay is, right? kitty litter! But, did you know that it is found in four different varieties? Potassium (K), sodium (Na), calcium (Ca), and aluminium (Al).

 

Sodium bentonite expands when wet, absorbing as much as several times its dry mass in water.
Calcium bentonite is a useful adsorbent of ions in solution, as well as fats and oils. It is the main active ingredient of fuller's earth, probably one of the earliest industrial cleaning agents. It is also the base for commercial kitty litter.
Herein lies the issue, they both are widely used and may even be mixed in the same bag depending on the manufacturer. Even buying bentonite directly from a clay (pottery) supplies house may result in getting sodium bentonite causing serious swelling after pressing the nozzle.
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Bottom line for any type of bentonite clay is to carry a drill bit set with you and hand ream the nozzles before firing the rockets. I do this right before assembling my dolas, fire off endburners or launch hot coreburners. Some amateurs have shown 25% restriction in smaller endburning rocket nozzles in humid locations so come prepared, a twist bit is cheap insurance.

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I love you dag! :)

 

Here is what i been doing wrong, too much clay past the washer line if i understand corectly. i was focusing too much replication of estes E9 rocket motor, filling clay the spindle and leaving 1/8" nipple available to expose bp for fuse. sounds like im putting too much clay.

 

see photo

 

post-20673-0-20090900-1471877634_thumb.jpg

Edited by joeyz
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Yes, keep in mind that even HP rockets use a VERY short throat. Love ya too, man! :P

 

http://4.bp.blogspot.com/_Chz8N61cyvI/Rw-aVI366BI/AAAAAAAAAOc/MaOdMPHKODY/s320/Nozzle_CrossSection.jpg

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i see that now! the choke point (washer line), throat can be longer but needs to be moderately tapered to direct gases and not restrict them to cause back pressure as i have been doing.

 

i was pressing clay too far up the spindle, creating a straw throat if you will. no wonder my rockets have been screwing up since i changed from homemade rockets spindle and hammer to professional tools and press. its been driving me bananas on why my homemade rockets work fine and my pro tool rockets are cato or other malfunctions. makes sense, i am simply restricting the flow of gases which definately explains the blowout. i went back and measured the clay on blowout rocket, clay was a total length of 1" and that choke point (washer line) was 1/2" thick, straw tube chamber effect above the washer line. i thought making the clay thicker/deeper chamber adds more strength to hold plug in place and prevents loss of pressure because the heat, pressure and gases cant erode the clay plug ID so fast, keeping the diameter same size during 12 secs of flight. no wonder why i saw a foot long stream beam of narrow fire. damn, i been screwing up, too much clay and directing gases into a long chamber, pin point plasma cutter lol

 

your forensic analysis has really opened my eyeballs, SEE PHOTO...

 

post-20673-0-85154300-1471879451_thumb.jpg

Edited by joeyz
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