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DynaSoar

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I build a tracking smoke can to fit my mach buster, and pretty much anything else 29mm or bigger.

Pieces:
4" BT50
Base of a two peice PNC50
Weird piece left over from a BT50 sized nose and tail cone, I forget what kit -- Bullpup? Anyway, it fit the tube and had a hole in it.

Could use both peices from a two piece nose, and cut a hole in the tip of the nose.

Glue it together, tie some triple-loop 150 lbs kevlar thread (loop length 12") through the base and run that through a snap swivel.

At launch time, squeeze marking chalk into the hole, and load the can hole up (base/cord down) in the BT, under the chute.

Charge goes off, blows off nose, that pulls out can, which helps push of chute. When the can comes free it turns open end down and starts dumping. Doesn't dump inside, like powder rolled in wadding can (unless it's coming down nose first and the cone is still on, at which point spilled powder is the least of your worries).

Worked like a dream on the shakedown of my mach buster, but only gave 4 seconds of smoke. Smaller hole, more time but less smoke. Maybe a longer tube on the next one. And maybe darker chalk. Orange isn't really that visible. Maybe charcoal powder? Seems lighter than chalk to me.
 

Silverleaf

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Can you post a couple pics please ?

I like the sound of this, but i'm awaiting surgury on my knee and am in a drug-induced fog and not picturing it clearly.

Sounds great !
 

DynaSoar

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Originally posted by Silverleaf
Can you post a couple pics please ?

I like the sound of this, but i'm awaiting surgury on my knee and am in a drug-induced fog and not picturing it clearly.

Sounds great !
PEEKchurs? We doan take no steenkeeng PEEKchurs.

I drew one with instructions.

Howzit?
 

BlueNinja

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I was thinking of something just like this, only utilizing dry Ice. When I think about it for a while, the DI wouldn't put off enough fog.
 

gary

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Hey!! This thread has given me some ideas!! I am in the middle of a 1.5X upscale Estes Tomcat project and in the early stages of annother project that also has "empty tubes" like the Tomcat....What I was thinking was to add a payload bay in the side tubes with chalk inside and holes top and bottom so the chalk can leave a nice twin contrail behind the model on boost and coast. I might be able to time it so the chalk runs out somewhere near ejection OR allow it to last longer so it still has a "smoke trail" during glide!!

Hmmmmmmmm I knew I liked this forum...

Gary
 

DynaSoar

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Originally posted by Gary
Hey!! This thread has given me some ideas!! I am in the middle of a 1.5X upscale Estes Tomcat project and in the early stages of annother project that also has "empty tubes" like the Tomcat....What I was thinking was to add a payload bay in the side tubes with chalk inside and holes top and bottom so the chalk can leave a nice twin contrail behind the model on boost and coast. I might be able to time it so the chalk runs out somewhere near ejection OR allow it to last longer so it still has a "smoke trail" during glide!!

Hmmmmmmmm I knew I liked this forum...

Gary
Ninja's dry ice idea has a problem: it would freeze the chute solid, unless it were insulated and that'd mean much weight.

I'd originally had the idea for putting an altimeter into a bird without a payload bay, using some sort of quick/positive retention system for the cap.

Beware payload/smoke in side pods. That'll probably move your CG back.
 

gary

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Originally posted by DynaSoar
Ninja's dry ice idea has a problem: it would freeze the chute solid, unless it were insulated and that'd mean much weight.

Probably not worth it...not dense enough smoke anyway.

I'd originally had the idea for putting an altimeter into a bird without a payload bay, using some sort of quick/positive retention system for the cap.

Beware payload/smoke in side pods. That'll probably move your CG back.
Not if the payload bay is at the CG location (Or in front of it for that matter).

Gary
 

shockwaveriderz

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dyna:
uisng fireworks smoke grenades? I was thinking with a timer you could ignite it at apogee......
 

gary

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Originally posted by shockwaveriderz
dyna:
uisng FIreworks smoke grenades? I was thinking with a timer you could ignite it at apogee......
Isn't that illegal?...It is here in Canada.

Gary.
 

gary

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Well I'm not 100% on laws in the States but here in Canada it is illegal to put any kind of fireworks into a rocket....

Thos candle things look like they MIGHT be ok but I would check first.

Gary
 

DynaSoar

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Originally posted by shockwaveriderz
dyna:
uisng fireworks smoke grenades? I was thinking with a timer you could ignite it at apogee......
Against NAR and "normal" TRA rules, possibly allowable under EX rules. There's also "cold smoke" canisters (see one of the Nike Smoke reviews on EMRR).

I don't care much for pyrotechnics beyond power plants. I'd rather extend other existing technologies.
 

Bill

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Originally posted by Blue_Ninja_150
I was thinking of something just like this, only utilizing dry Ice. When I think about it for a while, the DI wouldn't put off enough fog.

I would be really concerned that the gas slowly pushes the nose cone off while the rocket is sitting on the pad under a hot sun.


Bill
 

DynaSoar

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Originally posted by Bill
I would be really concerned that the gas slowly pushes the nose cone off while the rocket is sitting on the pad under a hot sun.


Bill
Yeah but just think of how realistic it would look with all that vapor coming out of the vents.
 

Mad Rocketeer

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Yeah. Seems like if you vent it (similar to parachute compartments for high flyers or altimeter bays), you could handle the vapor prior to launch and still get an ejection later. You'd have to do some experimenting and get the nose friction right, but hey, that's much of the fun, isn't it? :)
 

gary

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[QUOTEYeah but just think of how realistic it would look with all that vapor coming out of the vents. [/QUOTE]

If you want "realistic vapor" go hybrid man then you really ARE venting oxidiser....Very cool.

Gary
 

DynaSoar

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Originally posted by Gary
[QUOTEYeah but just think of how realistic it would look with all that vapor coming out of the vents.


If you want "realistic vapor" go hybrid man then you really ARE venting oxidiser....Very cool.

Gary
[/QUOTE]

Is there a 24mm hybrid certified yet?
 

Karl

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Erm the closest thing to 24mm is the Micro Hybrid available over here in the UK , it is 22mm in dia (7/8")

Url :
http://www.hpr.org.uk/mhybrid/

Karl

Edit :
Im not sure if there is a legal way of igniting these tho'
 

BlueNinja

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Doktor DynaSoar has a point there, it would look awesome, vent it out the back next to the motor :D . And, if you put the holder in the aft Cr somehow, the motor *might* heat it up during flight, leaving for quite a smoker during recovery. You can buy smoke grenades here for +- .75, however IMHO those burn longer than the normal recovery period for a rocket that it could be visibly used in. Not good if flying on grass :eek:
 

gary

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Originally posted by Karl
Erm the closest thing to 24mm is the Micro Hybrid available over here in the UK , it is 22mm in dia (7/8")

Url :
http://www.hpr.org.uk/mhybrid/

Karl

Edit :
Im not sure if there is a legal way of igniting these tho'
Now you are talking my language...Microhybids are ignited with regular Estes ignitors and a paper match. No pyro! Unfortunately the tank does not vent so no pre-launch steam at all...

Gary
 

DynaSoar

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Originally posted by Gary
Now you are talking my language...Microhybids are ignited with regular Estes ignitors and a paper match. No pyro! Unfortunately the tank does not vent so no pre-launch steam at all...

Gary
I really wish someone would build a G or less hybrid with an ejection system and get it certified. There needs to be acceptable physical proof for making hybrids an available option without certification. Hybrids are inherently safer than solid fuel/oxidizer grains. I think if one were certified, NAR and TRA would be happy to bring hybrids out of level-cert-required status.

They already use a pressurized gas system. Including a second, based on air, for ejection, shouldn't be too great a techno-feat.

For ignition, what about a 13mm or even micro-max motor (booster, plugged, or ejection charge vented out) pointed into the hybrid nozzle, used to ignite it, itself set off by nothing more high powered than an Estes Electron beam or equivalent and a regular igniter? A relay or just a parallel connection could open the valve.

Come on, folks, it's only rocket science. Like Ozy said, welcome to the 21st century.
 

shockwaveriderz

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dyna theres an old saying: great minds think alike.......anyway.....SkyRipper Systems will soon have an affordable G Hybrid available..... also as far as a nonpyrotechnic solution for a recovery system ejection system I suggest using nitrinol "shaped memory alloy"wire activated by either the outoput of a timer or altimeter........I won't go into the details bit suffice to say that this wire, when heated bu a small electrical current will do amazing things.....imagine if it was a compressed spring and then at apogee the altimer sends a current to this compresses nitrinol wire compressed spring and it immediately decompresses pushing out the laundry...... this is my idea, if anybody does it I will sue....

An alternate is , last night in bed where I do all my great thinking about all things rocketry before I conk out, I was thinking why not use a micro-maxx engine in a piston activated by an altimeter or timer to push the piston and recovery system out of a rocket?
 

shockwaveriderz

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dyna: the only problem I can see with using a MM or 13mm as an igniter for a hybrid is that most curent hybrids use ported cylindrical cores whcih are ignited at the top and not the bottom of the fuel grain..... I suppose you could place it at the top...but then it would probbaly clog up the hybrid engine....thats why they use APCP chunks at the top to ignite hybrid engines......
 

DynaSoar

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Originally posted by shockwaveriderz
dyna theres an old saying: great minds think alike.......anyway.....SkyRipper Systems will soon have an affordable G Hybrid available..... also as far as a nonpyrotechnic solution for a recovery system ejection system I suggest using nitrinol "shaped memory alloy"wire activated by either the outoput of a timer or altimeter........I won't go into the details bit suffice to say that this wire, when heated bu a small electrical current will do amazing things.....imagine if it was a compressed spring and then at apogee the altimer sends a current to this compresses nitrinol wire compressed spring and it immediately decompresses pushing out the laundry...... this is my idea, if anybody does it I will sue....

An alternate is , last night in bed where I do all my great thinking about all things rocketry before I conk out, I was thinking why not use a micro-maxx engine in a piston activated by an altimeter or timer to push the piston and recovery system out of a rocket?
If it can light an engine, it can open a valve. On, say, a CO2 cylinder. Or a second nitrous cylinder. Or just air, refilled at the gas station tire pump. No pyro involved. Geez, another potential project.

Well, if someone gets a sub-H hybrid TRA/NAR certified, I'll do this.

I know nitrinol. I was a judge at last year's high school science fair for the American Indians in Science and Engineering Society. A high school junior had built two robot bugs with legs of nitrinol that walked because of alternate heat applied. Amazing stuff, amazing girl.

And to save double replies: See, I don't know enough about hybrids yet. On the other hand, a motor firing up is firing into the top too.

MORE BETTER STUFF FASTER!
 
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