bp rockets

[allrocketspsl]

count fast lol! umm yeah ill fix that, just gimme a month or so. here's a resubmit for plain ole stars, can't redo the multibreak at the moment...

 

 

http://www.youtube.com/watch?v=d6aNeUtyXMk

 

 

i know its not the best, at least it was more than 3 seconds...

 

great job mate you have really improved from when I first saw you on YT!Keep going!!!! All

[Juiceh]

count fast lol! umm yeah ill fix that, just gimme a month or so. here's a resubmit for plain ole stars, can't redo the multibreak at the moment...

 

 

http://www.youtube.com/watch?v=d6aNeUtyXMk

 

 

i know its not the best, at least it was more than 3 seconds...

How are you fusing your shells to the motor? Looks like you took a shell that had about 3 seconds of time fuse and stuck it on the motor. If so, don't use time fuse in rocket headers. Use blackmatch in the shells passfire tube instead of time fuse, you want the header going off with no delay, the rocket motor is the delay. That way you won't have burning stars landing in the field. You don't want to be responsible for one of them out of control California forest fires do ya?

[vh718]

UPDATEUPDATE: since no one is in need of ball mill jars the new GRAND prize will be: FAMEand knowing you gave it your all!!!!!!!!!!!!!!!!!!!!!!!!!!

 

now i have to enter

[californiapyro]

haha, i took that one to NV to launch. and yeah, it was originally going to be mortar-launched, but i changed my mind. it was a spolette.

[guntoteninfadel]

I think for the contest I am going to use 3 sec time fuse from the exhaust to the header so I wont have to worry about the delay in the motor. I have to look at my other videos because I doubt I will be at apogee. I am using DUT tooling (guess what that is ) and Im pretty sure there is at least a 2-2.5 sec burn phase. Should be fine in any case.

[vh718]

dirt ugly tooling?

[allrocketspsl]

i was wondering what that meant thanls for the clarification V,All

[dagabu]

The three second break thing is going to be difficult since a good bulkhead of fuel should be at least two increments of delay but most BP burns around 3 seconds per inch in a column so without a clay bulkhead, you would only get 1" of bulkhead to play with to hold the pressures.

 

With only three seconds of delay and a bulkhead of only 1", a lower pressure motor is needed so I am making nozzleless rockets to carry my payload to about 150' when they break.

 

Looks like I need to go test some motors huh?

 

-dag

[californiapyro]

oh, i was thinking "dagabu universal tooling"

[allrocketspsl]

The three second break thing is going to be difficult since a good bulkhead of fuel should be at least two increments of delay but most BP burns around 3 seconds per inch in a column so without a clay bulkhead, you would only get 1" of bulkhead to play with to hold the pressures.

 

With only three seconds of delay and a bulkhead of only 1", a lower pressure motor is needed so I am making nozzleless rockets to carry my payload to about 150' when they break.

 

Looks like I need to go test some motors huh?

 

 

-dag

 

yup,since my fuels made like old fashion chinese makers made theirs,screening five times then granulating and drying for three weeks or more I only need 5mm of C6 to give me two seconds,my 1 and 2 cored burn in one second,thats three!But for me one more second is apogee four total.Thats breaking at 300 feet

[dagabu]

yup,since my fuels made like old fashion chinese makers made theirs,screening five times then granulating and drying for three weeks or more I only need 5mm of C6 to give me two seconds,my 1 and 2 cored burn in one second,thats three!But for me one more second is apogee four total.Thats breaking at 300 feet

 

WOW! Three weeks? I dry mine over night and it is bone dry. My opinion is that the faster BP makes for a longer column and that makes a better bulkhead. I have Willow and Cedar (fast BP) but didnt make any for this contest. Stick and wick tonight, we will see.

 

-dag

[allrocketspsl]

WOW! Three weeks? I dry mine over night and it is bone dry. My opinion is that the faster BP makes for a longer column and that makes a better bulkhead. I have Willow and Cedar (fast BP) but didnt make any for this contest. Stick and wick tonight, we will see.

 

-dag

 

yeah and here in sunny florida the humidy has some play,I made a batch once and progressively over two weeks the rockets were behaving differently, each one,figured the bp was drying out over said period,first were sluggish then faster and faster,remember I use 57/34/9 so more charcoal longer drying time even though kno3 is hydroscopic as it sucks up the charcoal which I use more of well my point mate! I look forward to your wick and stick test! Im watching you!!

[Mumbles]

If your KNO3 is hygroscopic, you may want to get better quality nitrate. It really shouldn't absorb much water at all. Sealing up the motors in a bag with a pack of dessicant works well too for storage. I more often hear about clay nozzles absorbing water and swelling. If you're not near the red line, this could cause the increase in performance you describe.

 

Three weeks does seem awfully long. I make 1/2"+ cut stars containing significantly more charcoal and significantly more water that dry naturally within 3 weeks even with very high humidity. A fan does wonders in getting things to dry. It probably shouldn't take you more than 3-4 days maximum to dry granulated composition.

[allrocketspsl]

If your KNO3 is hygroscopic, you may want to get better quality nitrate. It really shouldn't absorb much water at all. Sealing up the motors in a bag with a pack of dessicant works well too for storage. I more often hear about clay nozzles absorbing water and swelling. If you're not near the red line, this could cause the increase in performance you describe.

 

Three weeks does seem awfully long. I make 1/2"+ cut stars containing significantly more charcoal and significantly more water that dry naturally within 3 weeks even with very high humidity. A fan does wonders in getting things to dry. It probably shouldn't take you more than 3-4 days maximum to dry granulated composition.

 

I see what you mean mate,I dont have nozzel problems since I ram fly same or within a day,with 57/34/9 as fuel Im at red line believe it or not but theres a reason why I make them this way! thanks! All

[Mumbles]

I understand now. When you said batch, I originally thought you meant a batch of rocket motors.

[WSM]

If your KNO3 is hygroscopic, you may want to get better quality nitrate. It really shouldn't absorb much water at all. Sealing up the motors in a bag with a pack of dessicant works well too for storage. I more often hear about clay nozzles absorbing water and swelling. If you're not near the red line, this could cause the increase in performance you describe.

 

Three weeks does seem awfully long. I make 1/2"+ cut stars containing significantly more charcoal and significantly more water that dry naturally within 3 weeks even with very high humidity. A fan does wonders in getting things to dry. It probably shouldn't take you more than 3-4 days maximum to dry granulated composition.

 

I agree with Mumbles, and will add: you may want to dissolve and recrystalize your potassium nitrate to purify it, then grind it after it's dried. Crystallization is nature's way of purification.

 

WSM

[dagabu]

I look forward to your wick and stick test! Im watching you!!

 

It was a teaching weekend, the motors I made will be fired another night

 

Thunderr1 did a great job and his motors were made from BP he granulated just the other day!

 

-dag

[allrocketspsl]

looks like I will squeeze in my bp will be 3 tomorrow! Interesting info ,yeah thunder1 has it dialed in with great motors,some long tails for nozzeless,longest Ive seen so far!

[allrocketspsl]

If your KNO3 is hygroscopic, you may want to get better quality nitrate. It really shouldn't absorb much water at all. Sealing up the motors in a bag with a pack of dessicant works well too for storage. I more often hear about clay nozzles absorbing water and swelling. If you're not near the red line, this could cause the increase in performance you describe.

 

Three weeks does seem awfully long. I make 1/2"+ cut stars containing significantly more charcoal and significantly more water that dry naturally within 3 weeks even with very high humidity. A fan does wonders in getting things to dry. It probably shouldn't take you more than 3-4 days maximum to dry granulated composition.

 

you just made me think,when I get my kno3 I will use my food saver to suck the o out of it to store,did some engines with it ,great for rocket motors to keep for long time!! TY,All

[allrocketspsl]

It was a teaching weekend, the motors I made will be fired another night

 

Thunderr1 did a great job and his motors were made from BP he granulated just the other day!

 

-dag

 

you can use granulated bp on nozzeless?

[guntoteninfadel]

You make nozzeless just like nozzled, cept without the nozzle!

[WSM]

you can use granulated bp on nozzeless?

 

Home made granulated, not commercial (without special equipment). Ramming or pressing turns all those little grains into one, solid grain which burns evenly to produce the thrust needed to drive the rocket skyward .

 

WSM

[dagabu]

you can use granulated bp on nozzeless?

 

Yes, but only the small grains like 7FA, Meal-D and Fuse powder. As WSM says, you need to consolidate the grains and larger grains (4FA and larger) take a lot of pressure to make into a solid grain.

 

I make my BP fuel by milling all the chems together for an hour, adding 2% dextrin and whetting with 11-15% water and 5% alcohol making baseball sized balls form it and pressing it through an 8 mesh screen. Let dry overnight and press rockets!

 

-dag

[allrocketspsl]

Yes, but only the small grains like 7FA, Meal-D and Fuse powder. As WSM says, you need to consolidate the grains and larger grains (4FA and larger) take a lot of pressure to make into a solid grain.

 

I make my BP fuel by milling all the chems together for an hour, adding 2% dextrin and whetting with 11-15% water and 5% alcohol making baseball sized balls form it and pressing it through an 8 mesh screen. Let dry overnight and press rockets!

 

-dag

 

well I think Im going to try a nozzeless with a star header,but using meal, not granulated since i only ram and aint no way Im going to consolidate the fuel by ramming, for the contest, two others my usual nozzeled

one farfelle(hopefully with turd stars I can get a pistil)and one timed reports(two rings)

[guntoteninfadel]

You can consolidate the granulated. I use 3-4% dextrin and granulate with a screen. Really cuts down on the dust and generally dirtyness of the whole procedure. I think I could "feel" the grain when it consolidated when I was ramming. 8-9 good whacks with the dead blow and it is in. Hand ramming, while probably not superior to pressing, does have its own merits!

 

I am looking forward to try the corning thing as I do have a press now. Just waiting on my bp puck press from DG enterprises! Thats a hint D if your reading this .

Edited August 23, 2011 by guntoteninfadel