end burner idea

[leedrill]

dont know if anyone has tried it or if it will work very well but want to have a go at it just for fun

 

my idea is {sorry for no drawing hope you all get what i mean } press in a 7.5" long tube 1" id with nozzle, about 3.5" of whistle to get the motor really moving and then a nice short delay something with a really bright tail maybe slow burning about 0.5" leaving about 3" so mark the rammer above the delay and press in and clay end plug then hot BP+Ti and another end plug with a passfire hole grab a drill fixture and basicly make the end into a hummer

then drill into the delay on the motor portion and insert two fuses one to lead to a small stick buster and one to the hummer portion making sure the stick is broken first then add a report to the end

id like to hear peoples thought on the i think if done right the novelty would be worth the extra effort

[WonderBoy]

That sounds like it would get complicated pretty quickly. Maybe you could have the hummer as a seperate component so it is not attached to the stick? I have not done that exactly, but I have made 2 rockets that have similar characteristics, both were pretty neat.

 

One I call a "whistle assisted stinger". Using a "standard" 1lb BP spindle, I pressed some whistle, then an increment of clay, then finished the motor with BP. It was ignited by a fuse in the BP section, just above the clay nozzle. It spun up very briefly, then ripped into the sky.

 

 

The other one was a 2 stage rocket. It had a "standard" BP motor first stage, and a stinger as the second stage. Just before the first stage burned out, it lit some quickmatch going to the vent hole of the stinger. If I were to do it again, I would use some metal in the stinger so the spin up is more apparent. (Turn up your volume so you can hear it)

 

 

 

WB

Edited October 11, 2013 by WonderBoy

[Juiceh]

One I call a "whistle assisted stinger". Using a "standard" 1lb BP spindle, I pressed some whistle, then an increment of clay, then finished the motor with BP. It was ignited by a fuse in the BP section, just above the clay nozzle. It spun up very briefly, then ripped into the sky.

 

What whistle formula did you use? How many increments? 75:15:10 BP? Did you drill side hole vents just above the clay nozzle and begin ignition there? NEPT tube? If so, thick wall or regular? Pics?

[leedrill]

i was unaware of different thicknesses of nept tubes can some one elaborate on what is out there

 

also wb i dont know how i would feel drilling into bp with ti in it i guess there is ways around that but even still i really dislike metal on my spindles

 

ill be giving the nozzless whistle stinger a go just on the standard base which i think will be a great little piece but ive been trying to come up with a way to get a skirt in doing so i think ill just press one incriment of bp with some hard wood char in addition , then to above the spindle with whistle and then delay

and well your second vid makes me think yeah 2 stage will make it a lot less complicated and with the motor i just suggested will be awesome

[kpknd]

In the second video, what percentage of titanium did you use in your burst? Was it titanium?

[WonderBoy]

Lee,

 

The only difference in thickness, in commonly available NEPT is in the 3/4" size. There are 1/8" wall and 3/16" wall tubes. I would not recommend drilling into comp with metal either, I would pre-drill the hole and press the fuse into the comp. Again, this is not recommended, but I often make my own spindles, so if I were to press metal around the spindle, I would make a sacrificial spindle that I didn't care about ruining, and use proper PPE eg. press shield, gloves etc.

 

What do you mean by, "trying to come up with a way to get a skirt"? Are you talking about the spray of sparks during the initial spin-up? I wonder if you could find a way to "protect" the spindle with a non-metal containing comp. How are you thinking of doing a two stage setup?

 

Juiceh,

 

I used normal NaBenz whistle. About a 2" column. Normal milled BP in the "stinger" section. I did drill one 1/8" vent just above the nozzle, so at about 2-3/4" from the bottom of the motor. It was lit from this vent hole. Normal NEPTubes. Sorry, no photos. Just looks like a normal cored BP motor, but with a fuse coming out of the tube about 2-3/4" from the bottom. I used 1/8" steel rod as the launch pin, and I also made a "hoop" to help keep it going straight. I do have photos of the 2 stage motor.

 

kp,

 

I have no idea. I made that rocket maybe 4 years ago. IIRC I just filled the empty space above the bulkhead with flash and then added a pinch of sponge Ti.

 

 

WB

[leedrill]

by skirt yes i mean the spray from the vent and ive come up with a couple of ideas for the 2 stage now but still cant quite figure out how to attach the top motor strong enough to not wreck the fuse setup on the first motors spin up {yes i know it might seem like a silly idea but i have to admit i like those as long as they are safe }

 

and i think the best thing i can come up with so far is not really a two stage but would be pretty cool but would just make a stinger as normal {or what ever way you wanted } then press up a tube with solid clay bottom plug then say bp+ti about the same length as the stinger and just lower than half way on that tube drill two hole the same as a twin vented hummer but drill the holes at 45 degrees in from the vertical of the tube {hope you get what i mean } that way you will get some lift out of the second stage but a really nice sound and skirt and then id just drill below the clay plug on the stinger on the bottom and insert black match from that hole to both the holes on the { i guess youd call it a lift hummer or something } and gum tape over them so the timing is quick a report on top and would be pretty cool seems like a bit of work but would have to say that design would be easy enough and even not a true 2 stage would seem like one to someone from a far