It's official, Pee-Wee Payload is Now a Provisional NAR event!

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If this weather clears out this weekend I hope to get some flights in. I have my brother and my wife for trackers. I also have my new prototype ready to fly. It weighs almost 2 grams lighter. granted im launching of a rod so im not going to hit extreme altitudes but should give mt a base line for making them better
 
Was a very Busy Sport Launch Last weekend, with a fun contest, TARC flights and a ton of Scouts out sport flying. but I did manage to launch all three motor class PeeWee Payload models once during the day with the Help of the Better 2/3rds.

Have to say these first Rod launched flights were a bit surprising. The first launched was on an OLD OOP 1/4A3-3T Apogee motor with 2 3.5g loads. the model seemed to struggle off the pad only getting maybe 45feet. I'm thinking it either hung on the rod a bit or it was a weak motor.

Launching the 14mm 1/2A3-4T with 3- 3.5g loads Wow! out of sight high. in fact since the streamer failed to fully deploy I didn't even see the model until it was about 30feet from the ground. One of the other flyers said he believed the model was well over 350-400 feet up at ejection.

I was impressed with the speed and altitude of the 1/8A PeeWee with a single 3.5g load flying on a mmx-II motor. flown from a tower (lugless) she easily hit the 150-175ft level.

leasons learned, I need to attach the streamers closer to the ejecting back end of the model rather then the nose area of the shockcord.
Pics still in the camera, I'll see what if anything I caught in the next day or two.
 
leasons learned, I need to attach the streamers closer to the ejecting back end of the model rather then the nose area of the shockcord.

Why?

I would think if you placed them too far back you would develop new problems a) deployment would take bit longer which would be bad for a duration event and b) if the ejection was weak (does that happen in MMX motors?) the streamer might not deploy at all.

This isn't based on knowledge or experience with MMX, just trying to think things through and understand.
 
its for altitude not duration if in thinking right. I have found that i stuff the shock cord into the payload section and stuff the teflon streamer into the bottom section on top of the motor. it blows it every time. im going to a launch this weekend so i should have a good chance to have some people help me track the altitude. the weather has been crazy if im working it is great out and if im off it rains or the wind is blowing way to hard to launch
 
its for altitude not duration if in thinking right. I have found that i stuff the shock cord into the payload section and stuff the teflon streamer into the bottom section on top of the motor. it blows it every time. im going to a launch this weekend so i should have a good chance to have some people help me track the altitude. the weather has been crazy if im working it is great out and if im off it rains or the wind is blowing way to hard to launch

Correct:
On two of the the 3 models with the Streamers installed in the body above the break, the streamers were not dragged completely out of the body at ejection, I think the aft section had to much time to slow down before hitting the end of the shockline.
Yes putting the stream in the aft section does make it automatic but I'm trying to make these base models "qualifiers" that anyone can build and fly. For most people its almost automatic to loading the streamer in the body, just trying to make the base design simple. I'm sure my own competition models will like have the streamers located in the aft coupler.
 
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I've been thinking about this for a little while. If mismatched ejection charge delay is the real problem with getting better altitudes, is there anything that can be done to fix it by the modeler?

High power rockets usually have a separate ejection charge. Is that allowed in Pee-Wee competition?

Could one of the following designs be made to work?

* Plug the ejection charge end of the motor with cardboard + superglue causing the ejection charge to go out the nozzle instead, possibly adding to thrust and giving more coasting time. Add a very simple timer+ejection charge to get the recovery device out
* Plug the ejection charge end of the motor with a fuse and glue it in so perhaps most of the ejection charge goes back out the nozzle. stick the real ejection charge on the other end of fuse, crating a longer delayed engine
* Upsize the outer body tube so you have a motor mount. Drill slots in the rings so gas can go through the back. Put a bulk head close to the ejection side of the engine with a hole in it for a fuse with ejection charge on the other side. ejection gas then lights the fuse and most of it gets kicked out the back of the rocket.

If an extra ejection charge isn't allowed, would some other mechanism to separate the body tubes work on this scale?

Maybe some combination of engine stuff above with holding the two body tube sections together with:
* a couple of electronic fuses
* regular fuse wrapped around the joint

or a solenoid to push the two sections apart?

Could any of these be made to be a net positive?

Or would any of this just be considered cheating? Wouldn't want that.
 
I've been thinking about this for a little while. If mismatched ejection charge delay is the real problem with getting better altitudes, is there anything that can be done to fix it by the modeler?

High power rockets usually have a separate ejection charge. Is that allowed in Pee-Wee competition?

Could one of the following designs be made to work?

* Plug the ejection charge end of the motor with cardboard + superglue causing the ejection charge to go out the nozzle instead, possibly adding to thrust and giving more coasting time. Add a very simple timer+ejection charge to get the recovery device out
* Plug the ejection charge end of the motor with a fuse and glue it in so perhaps most of the ejection charge goes back out the nozzle. stick the real ejection charge on the other end of fuse, crating a longer delayed engine
* Upsize the outer body tube so you have a motor mount. Drill slots in the rings so gas can go through the back. Put a bulk head close to the ejection side of the engine with a hole in it for a fuse with ejection charge on the other side. ejection gas then lights the fuse and most of it gets kicked out the back of the rocket.

If an extra ejection charge isn't allowed, would some other mechanism to separate the body tubes work on this scale?

Maybe some combination of engine stuff above with holding the two body tube sections together with:
* a couple of electronic fuses
* regular fuse wrapped around the joint

or a solenoid to push the two sections apart?

Could any of these be made to be a net positive?

Or would any of this just be considered cheating? Wouldn't want that.

One of the very first things everyone must realize is ADDING ANYTHING to a motor; would be considered AS "Altering the Manufacturers intended use" and as such is strictly forbidden in NAR competition.
So NO none of your first options would be allowed in competition. To be honest it's not generally allowable even for sport flights at NAR sanctioned Launches.
Plugging motors is a VERY risky thing to do. I've seen several illegal epoxy plugged D12 motors Cato so is not something I'd do or recommend others do as well.

As with all things Micro; Mass is alway the enemy. Adding anything EXTRA to a competition model has it's tradeoffs in lowering altitude. NOT a good thing. for instance I have several 2 and 3 second micro ejection timers that can be run on small SuperCap Capictors. but the added mass of these tiny electronics and ejection charge out weigh the benifit gained. The couple extra grams actually being the projected ejection time to nearly that of the normal 1 second delay.

No it's just not in the cards to add electronic ejection to a micro Altitude event. I've had these staging times designed and manufactured for use in Scale model compeititons, where the uppers stage sustainer is either T3 or T4 diameter to fit the Supercaps.

Increasing the Airframe diameter in competiton models will also decrease the expected maxium altitude achived by our models. It would be possible to go up to say T2++ (.316" OD) without doing to much harm to the achived altituded, given that our minimum diameter models are Still going up at a pretty good clip when the 1-second delay goes off. We just have to keep in mind the fact that extra diameter = greater frontal area = larger DRAG surface which always reduces altutude performance.
 
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What about using a MicroMax NE motor with fuse and charge. No modification of the motor would be required.
 
What about using a MicroMax NE motor with fuse and charge. No modification of the motor would be required.

Doubt it would be allowed in Competition as you're still ADDING something (Fuse & ejection charge) to the motor, but more importantly "not using the motor as intended by the manufacturer".

Competition rules are pretty cut and dry when it comes to what can and can't be done with our pre-manufactured motors. The Pink Book rules are intended to level (as much as possible) the playing field for ALL who wish to compete.
 
One of the very first things everyone must realize is ADDING ANYTHING to a motor; would be considered AS "Altering the Manufacturers intended use" and as such is strictly forbidden in NAR competition.
So NO none of your first options would be allowed in competition. To be honest it's not generally allowable even for sport flights at NAR sanctioned Launches.
Plugging motors is a VERY risky thing to do. I've seen several illegal epoxy plugged D12 motors Cato so is not something I'd do or recommend others do as well.

As with all things Micro; Mass is alway the enemy. Adding anything EXTRA to a competition model has it's tradeoffs in lowering altitude. NOT a good thing. for instance I have several 2 and 3 second micro ejection timers that can be run on small SuperCap Capictors. but the added mass of these tiny electronics and ejection charge out weigh the benifit gained. The couple extra grams actually being the projected ejection time to nearly that of the normal 1 second delay.

No it's just not in the cards to add electronic ejection to a micro Altitude event. I've had these staging times designed and manufactured for use in Scale model compeititons, where the uppers stage sustainer is either T3 or T4 diameter to fit the Supercaps.

Increasing the Airframe diameter in competiton models will also decrease the expected maxium altitude achived by our models. It would be possible to go up to say T2++ (.316" OD) without doing to much harm to the achived altituded, given that our minimum diameter models are Still going up at a pretty good clip when the 1-second delay goes off. We just have to keep in mind the fact that extra diameter = greater frontal area = larger DRAG surface which always reduces altutude performance.

Thanks so much for the reply. Yeah, I figured it was a long shot, and probably dangerous. That's why I wanted to ask rather then try.

After posting, I ran some simulations in OpenRocket and came to about the same conclusion you did. Upscaling the body tube to let the gas out back caused it to apogee at 124 feet while the reference min diamater rocket sim'ed to 153. Doing a hybrid where there was a transition as far back as you can, got 145. If there was an an additional kick to the gas out the back, it might break even with the reference model. Not really worth it.

Adding a 3 second delay to the reference rocket sim'ed up to 213 feet, so there is almost 40% more altitude that's off the table because of the low ejection charge time. Adding weight to the sim until its back to the reference height, says the rocket has to have less then 1.7 grams additional weight to get any benefit from a longer delay. 1.7 grams is not that much play room.... That's very very little wiggle room for anything electronic. Like you said, probably not doable at all.

Anyway, thanks for the discussion. Was an interesting thought experiment.
 
Doubt it would be allowed in Competition as you're still ADDING something (Fuse & ejection charge) to the motor, but more importantly "not using the motor as intended by the manufacturer".

Competition rules are pretty cut and dry when it comes to what can and can't be done with our pre-manufactured motors. The Pink Book rules are intended to level (as much as possible) the playing field for ALL who wish to compete.

Even if there is a gap of say, 2 or more millimetres between the engine and fuse? They wouldn't actually be touching/overlapping in any way. Seems like a gray area.

Say you used a ejection charge with a fuse and the engine lit it, would that be any different really then having an ejection charge with fuse, with an electronic fuse on the other end, a battery, and a pressure switch, and the pressure of the engine gas caused the system to go?

Maybe your saying though, that the whole thought exercise is infeasible by the rules, since the engine specifically was designed with a 1 second delay therefore any lengthening of the delay by any means is a disqualifying offence? I wonder how the HPR rockets work within the rules here?
 
Even if there is a gap of say, 2 or more millimetres between the engine and fuse? They wouldn't actually be touching/overlapping in any way. Seems like a gray area.

Say you used a ejection charge with a fuse and the engine lit it, would that be any different really then having an ejection charge with fuse, with an electronic fuse on the other end, a battery, and a pressure switch, and the pressure of the engine gas caused the system to go?

Maybe your saying though, that the whole thought exercise is infeasible by the rules, since the engine specifically was designed with a 1 second delay therefore any lengthening of the delay by any means is a disqualifying offence? I wonder how the HPR rockets work within the rules here?

Adding a separation between the motor and fuse "Should" be legal. Having the motor ignite a fuse at liftoff would also be doable. We just can't Add anything physically attached to a manufactured motors that alters or enhances the performance of said motor. It's like adding a few extra grains of BP to get a stronger ejection charge. it's simply a NO-NO!
Gap staging a fuse would certainly be a grey area; The modeler would have to disclose the intention at check-in, Showing the Gap actually exists, then reassemble the model/system in front of the Check-in and possibly RSO before proceeding to the assigned launch pad. I personally see it as an area of possible mischief on a competition range.

In no way did I say the "any" lengthening of the -NE motors .854s average delay would be a disqualifier. What I said is we CAN NOT add anything physically to a manufactured motors. It may be possible to add some form of electronic ejection system or something like it, but they will have a dramatic lowering of expected altitude due to added mass, increased frontal area drag or both.

To answer your last question: HPR rocket motors are not flown in NAR Competition at all. Largest motor allowed currently would be G's where the 1500gram model /125g propellant limits are the cut-off, no "H" motors period.
 
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Adding a separation between the motor and fuse "Should" be legal. Having the motor ignite a fuse at liftoff would also be doable. We just can't Add anything physically attached to a manufactured motors that alters or enhances the performance of said motor. It's like adding a few extra grains of BP to get a stronger ejection charge. it's simply a NO-NO!
Gap staging a fuse would certainly be a grey area; The modeler would have to disclose the intention at check-in, Showing the Gap actually exists, then reassemble the model/system in front of the Check-in and possibly RSO before proceeding to the assigned launch pad. I personally see it as an area of possible mischief on a competition range.

In no way did I say the "any" lengthening of the -NE motors .854s average delay would be a disqualifier. What I said is we CAN NOT add anything physically to a manufactured motors. It may be possible to add some form of electronic ejection system or something like it, but they will have a dramatic lowering of expected altitude due to added mass, increased frontal area drag or both.

To answer your last question: HPR rocket motors are not flown in NAR Competition at all. Largest motor allowed currently would be G's where the 1500gram model /125g propellant limits are the cut-off, no "H" motors period.

So what about killing two birds with one stone here... There is not enough wiggle room in the body diameter to have anything but a minimal tube diameter. That means that the ejection gas needs to come out the sides. If you drilled a hole through the body tube right above where the engine sits, that would allow the ejection gas to leave the body on opposite sides of the body tube, hopefully cancelling out the sideways thrust. If you put some little round stickers or hole reinforcement stickers + plastic wrap over the holes during flight, it shouldn't add too much drag? The bonus would be, until the stickers are applied, you'd have a very nice window into the fuse mechanism, easily showing any gap. :)

Modelling the above, and assuming 0.28 grams of powder/fuse (total guess), its sim's to 193 feet. That beats the reference model of 153 by 40 feet. That assumes there is no affect from the sideways ejection. Maybe something more could be done with it like creating a balsa transition that funnels the gas angled downward a bit. But as is, it looks like it might work, assuming its legal.

Ah, I didn't realize there were no HPR rocket NAR competitions. Thanks for the info.
 
That could work if it gets through Check-in. Sounds like it's time to stop talking and start flight testing. Actual flights results never match simulated results generally 10-20% lower. Most of the actual flight results currently available have this particular event will top out around 18o - 208feet +/-.

Assuming you're using a standard .049 x 12" launch rod to calculate your sims the numbers seem about right. Actually the BTC's would be flying from floating head pistions with Non-Standard materal minimum diameter model airframes. Personally I've topped 200feet with this type 1/8A payload model while the Standard models were designed to be qualifiers so even novice flyers could enter these payload events.

Good to see others are looking at flying this provisional event. Hopefully if we get enough clubs flying 1/8A Payload it will be made a permanent event.
 
That could work if it gets through Check-in. Sounds like it's time to stop talking and start flight testing. Actual flights results never match simulated results generally 10-20% lower. Most of the actual flight results currently available have this particular event will top out around 18o - 208feet +/-.

Assuming you're using a standard .049 x 12" launch rod to calculate your sims the numbers seem about right. Actually the BTC's would be flying from floating head pistions with Non-Standard materal minimum diameter model airframes. Personally I've topped 200feet with this type 1/8A payload model while the Standard models were designed to be qualifiers so even novice flyers could enter these payload events.

Good to see others are looking at flying this provisional event. Hopefully if we get enough clubs flying 1/8A Payload it will be made a permanent event.

I might take a stab at it if I can dig up the appropriate parts and figure out the appropriate fuse/charge.

Another idea thats been kicking around the back of my head is a chemical means, rather then electrical or pyrotechnic. I really think it would be funny to use tiny mentos and diet soda. ;) but I wonder if baking soda/vinigar would work as an ejection gas generator with a pistion/pin replacing the fuse.
 
I might take a stab at it if I can dig up the appropriate parts and figure out the appropriate fuse/charge.

Another idea thats been kicking around the back of my head is a chemical means, rather then electrical or pyrotechnic. I really think it would be funny to use tiny mentos and diet soda. ;) but I wonder if baking soda/vinigar would work as an ejection gas generator with a pistion/pin replacing the fuse.

LOL!
I haven't tried it on anything this small. Would have to make or create some sort of waterproof capsule so as not to burst the body-tube but Acid/Base reactions would certainly create enough CO2 to easily pop a nose cone. Not sure if it would be enough behind a small piston to push out a streamer but it's certainly not beyond the pail:)
Been flying Pill bottle/35mm film can Alka Seltzer & water CO2 rockets with the Grandkids for a few years now. They create enough pressure to pop the bottle 15feet in the air pretty quickly on a 1/4 table of alka seltzer. Baking soda/vinegar would be a stronger (faster) reaction.

Alka Seltzer-a_(CO2) Rocket Parts & Pieces_06-2008.jpg

Alka Seltzer-d_(CO2) Rockets & fuji film Canister_07-04-08.jpg
 
LOL!
I haven't tried it on anything this small. Would have to make or create some sort of waterproof capsule so as not to burst the body-tube but Acid/Base reactions would certainly create enough CO2 to easily pop a nose cone. Not sure if it would be enough behind a small piston to push out a streamer but it's certainly not beyond the pail:)
Been flying Pill bottle/35mm film can Alka Seltzer & water CO2 rockets with the Grandkids for a few years now. They create enough pressure to pop the bottle 15feet in the air pretty quickly on a 1/4 table of alka seltzer. Baking soda/vinegar would be a stronger (faster) reaction.

Nice rockets. :)

I was thinking the piston would go the other way. The piston head would be at the bottom of the rocket right on top of the engine. it would have a rod that would go through a bulkhead and then pop a bag at the top causing the chemicals to mix. The real trick I think would be getting the delay right. After popping the bag, you'd want 2.5+ seconds before the nose popped. baking soda + vinegar might be too quick. Maybe an elephants toothpaste variant of hydrogen proxide and dry yeast would be slow enough. How long does the alka seltzer and water take to really start going?

Another thought I had yesterday is using gravity as an altimeter. put the liquid at the bottom and the powder at the top, in a couple of tiny cups, and just after apogee the rocket flips and the liquid gets up to where the powder is. This way, you wouldn't have to time the reaction at all. It should be as fast a reaction as possible in that case.

For the alka seltzer, can you use a solid pellet or do you have to powder it? If it could be solid, that might be easier to deal with. Just cut/shave down a piece to fit perfectly into the tube.

Do you think a coat of Elmers glue down the inside of the body tube would be enough waterproofing?
 
Nice rockets. :)

I was thinking the piston would go the other way. The piston head would be at the bottom of the rocket right on top of the engine. it would have a rod that would go through a bulkhead and then pop a bag at the top causing the chemicals to mix. The real trick I think would be getting the delay right. After popping the bag, you'd want 2.5+ seconds before the nose popped. baking soda + vinegar might be too quick. Maybe an elephants toothpaste variant of hydrogen proxide and dry yeast would be slow enough. How long does the alka seltzer and water take to really start going?

Another thought I had yesterday is using gravity as an altimeter. put the liquid at the bottom and the powder at the top, in a couple of tiny cups, and just after apogee the rocket flips and the liquid gets up to where the powder is. This way, you wouldn't have to time the reaction at all. It should be as fast a reaction as possible in that case.

For the alka seltzer, can you use a solid pellet or do you have to powder it? If it could be solid, that might be easier to deal with. Just cut/shave down a piece to fit perfectly into the tube.

Do you think a coat of Elmers glue down the inside of the body tube would be enough waterproofing?

There are several problem areas with the list of suggestions.
First concerning the inverted piston approach: What is intended to drive the bag popping rod? If expecting the ejection charge to do this in the confines of a minumim diameter T2+ (.281") body tube there is No way the charge won't push the entire contents bags and all from the model. Perhaps using a larger airframe, some of the gas could be redirected back out through spill holes but getting all of these variables right could take a great deal of tinkering time. Not to mention lose of achieved altitude with the greater frontal area and mass. I think I'll just table the piston puncture option for awhile.

Gravity as your altimeter has another problem: Have you considered the fact that as soon as the motor thrust ends, deceleration will cause the liquids to slam forward. This is exactly how we used mercury switches to close circuits igniting upper stage motors. If this deceleration is strong enough to throw heavy mercury forward in a split second it will certainly do the same to any other liquid putting an abrupt end to any "Normal" coast phase before ejection.
If I were to attempt this type of ejection delay I'd use baking soda/vinegar as it will product a largest volume of gas the quickest. At least a second or two would be needed. which would give the model at least a little time to coast before popping the Nose cone.

Alka Seltzer tablets are usually used in portions of a wafer, they are fairly slow reactions. In our pill bottle/35mm film canister rockets 1/4 tab is all that's needed. From the time the model is inverted onto some solid base(Concrete, Rock, Stepstone, etc) a 10sec countdown is about all that's needed before the pressure pops the top off the film can Launching the rocket. Probably way to long for use in an Payload Altitude model.

NO way would elmers waterproof the inside of a body tube. Wicking in waterthin CA would turn the tube into a semi-phenolic tube but that would also mean it has become very rigid and brittle possibly letting the pressure build up burst the tube. My best guess would be to find a Thin wall Polyethylene or Polybuterate tube that would fit inside the model body. These little capsules could be plugged with epoxy or solvent welded caps that would sever to make them liquid tight enough to hold the proposed liquid.
Here again we come to the problem of automatic mixing at deceleration. So we must either PLAN for this to happen and use a slow enough chemical combination to allow for the coasting travel we expect or find some other way to retard the liquid/powered or tablet mixing.
 
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The mercury in a mercury switch used for staging is not thrown forward. The mecury is an object in motion and it stays in motion. The rocket decelerates because thrust ends and air drag and gravity are the only forces left acting upon it and the mercury keeps moving, so the even though everything is still moving forward, the rocket is slowing down a bit while the mercury keeps moving at the same speed so that the mercusy switch housing and the contacts on the front end approach the liquid mercury and make contact completing the circuit.

The liquid does not slam forward, it keeps moving. The rocket appears to slam backward, even though it is still moving forward because it is slowing down relative to the liquid mercury.

https://en.wikipedia.org/wiki/Newton's_laws_of_motion
 
The mercury in a mercury switch used for staging is not thrown forward. The mecury is an object in motion and it stays in motion. The rocket decelerates because thrust ends and air drag and gravity are the only forces left acting upon it and the mercury keeps moving, so the even though everything is still moving forward, the rocket is slowing down a bit while the mercury keeps moving at the same speed so that the mercusy switch housing and the contacts on the front end approach the liquid mercury and make contact completing the circuit.

The liquid does not slam forward, it keeps moving. The rocket appears to slam backward, even though it is still moving forward because it is slowing down relative to the liquid mercury.

https://en.wikipedia.org/wiki/Newton's_laws_of_motion

The Physics is of coarse exactly correct; Just simpler to explain as described.
Whatever Liquid is chosen Will Indeed be slammed into the rapidly slowing, Not "Slowing down a Bit" model causing the condition as described. Weather the liquid hits the contacts or the contact hit the liquid is Totally immaterial to this process. We both know this condition occurs in Less then a second after burnout so for all intent and purpose your post is a Difference without Distinction. The major Point being the liquid would NOT stay in place until the model arcs over at apogee as suggested. My apologies for not wasting a bunch of time beating around the bush doing a complete physics lesson to explain why the idea in question would not work.
 
The Physics is of coarse exactly correct; Just simpler to explain as described.
Whatever Liquid is chosen Will Indeed be slammed into the rapidly slowing, Not "Slowing down a Bit" model causing the condition as described. Weather the liquid hits the contacts or the contact hit the liquid is Totally immaterial to this process. We both know this condition occurs in Less then a second after burnout so for all intent and purpose your post is a Difference without Distinction. The major Point being the liquid would NOT stay in place until the model arcs over at apogee as suggested. My apologies for not wasting a bunch of time beating around the bush doing a complete physics lesson to explain why the idea in question would not work.

Hmm... ok. so flipping over won't work. Yeah, so lets go with assuming the reaction will start as soon as the engine cuts off. We just need to find a combination that is around 4ish+ seconds to pop the nose then.

I have some bt-2's on order and a scale and I have a bunch of the chemicals already. I'll see if I can find one that will work when the scale comes in.

I'll look around for some water proof tubes too like you mentioned. I was also thinking maybe waterproofing a spent mmx casing might work ok. It would be much thicker so might withstand the stress better if glued? Might be too heavy though.

If nothing else, determining if 1 gram of chemicals is enough to pop a nose is worth the experiment. If we need more then that, this method will probably never work.
 
Why not use a booster motor with it butted up to a thin ply/balsa bulkhead fire proofed-ish with epoxy , no thrust lost, and no ejection also NO MODIFICATION. Then all you have to come up with is a very light electronic ejection system (and tiny if used in 13mm tubes or the aforementioned BT-2s)
 
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I saw the first few words of the title of this thread, and got excited - I thought it was going to say the new Pee-Wee Herman movie would have something to do with model rockets!
 
Ok. I completed a first test with failure. But learned a few things along the way...

I built a Fliskits Tiny Triskelion earlier and had the inner material from one of the engine centering rings left over. It made a perfect end cap. I then cut out about 1 inch of T2 and super glued on the end cap. I then filled it up pretty good with Elmers glue to coat the inside, let it dry a bit, wiped out the excess, and then let it dry the rest of the way. This piece weighed 0.3 grams. I then used some more T2 to cut a cylinder out of a alka seltzer tablet. On some spare alka selzer, I tested super glue to see if it would react. It does not react, and glues nicely.

So, I filled up the tube with water, put a small ring of glue around the top of the cylinder, and topped it off with the alka seltzer. The whole capsule came in at exactly 1.0 grams and it looks to be water tight. At least for several minutes. I still have it and see no water damage.

I carefully took a T2+ tube with two nose cones, and slid the finished capsule inside, replaced the nose cone, and then tested it by turning it on its side, and then counted. After a minute of counting, It was a clear failure since it would never be in the air that long. I took it a part and saw that it hadn't gotten much gas out yet. After another minute, I could see gas escaping between the tablet and the tube, so it eventually started working. I'm wondering if I used too much super glue. Also, I did not thin out the alka seltzer cylinder. It was the full tablet thickness. Probably too thick. I also after the fact realized I didn't sand down the nose cones at all, and I think they were probably on way too tight to do a good test.

So, in summary, the good:
* Building a capsule out of T2/paperboard worked.
* Water proofing with Elmers seems feasible.
* The weight is correct. 1 gram.

To be figured out:
* alka seltzer or alternative. alka seltzer seems to be too slow a reaction.
* if not alka seltzer, how to keep the powder and liquid separate. Will the cylinder method still work for baking soda or whatever?
 
Ok. I completed a first test with failure. But learned a few things along the way...

I built a Fliskits Tiny Triskelion earlier and had the inner material from one of the engine centering rings left over. It made a perfect end cap. I then cut out about 1 inch of T2 and super glued on the end cap. I then filled it up pretty good with Elmers glue to coat the inside, let it dry a bit, wiped out the excess, and then let it dry the rest of the way. This piece weighed 0.3 grams. I then used some more T2 to cut a cylinder out of a alka seltzer tablet. On some spare alka selzer, I tested super glue to see if it would react. It does not react, and glues nicely.

So, I filled up the tube with water, put a small ring of glue around the top of the cylinder, and topped it off with the alka seltzer. The whole capsule came in at exactly 1.0 grams and it looks to be water tight. At least for several minutes. I still have it and see no water damage.

I carefully took a T2+ tube with two nose cones, and slid the finished capsule inside, replaced the nose cone, and then tested it by turning it on its side, and then counted. After a minute of counting, It was a clear failure since it would never be in the air that long. I took it a part and saw that it hadn't gotten much gas out yet. After another minute, I could see gas escaping between the tablet and the tube, so it eventually started working. I'm wondering if I used too much super glue. Also, I did not thin out the alka seltzer cylinder. It was the full tablet thickness. Probably too thick. I also after the fact realized I didn't sand down the nose cones at all, and I think they were probably on way too tight to do a good test.

So, in summary, the good:
* Building a capsule out of T2/paperboard worked.
* Water proofing with Elmers seems feasible.
* The weight is correct. 1 gram.

To be figured out:
* alka seltzer or alternative. alka seltzer seems to be too slow a reaction.
* if not alka seltzer, how to keep the powder and liquid separate. Will the cylinder method still work for baking soda or whatever?

Kfox1111:
I strongly suggest starting a new thread with regard to this chemical reaction deployment micro.
I'm sure if there is any interest others will join in on that thread.
At this point I would suggest to get any kind of rapid gas gereration you will need for proplution or recovery deployment a much more energetic combination will be needed. First guess would be a Base/Acid combo (Baking soda/vinegar) immediately comes to mind which should likely give the necessary rapid CO2 development to deploy a recovery system. It also makes MUCH more sense to use a Plastic Soda straw with the same OD has T2 tubing for the liquid capsule body then the heavier glue soaked paper tube. Both changes should save a few tenths of a gram.
 
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