Model Rocketry Thread

[Vostok]

As promised, a video and a \'result\' picture of the last launch....

as you can see, it was a bit more energetic than my last few, which I call progress, of sorts.

It also goes to show that no matter how sleek and shiny your rocket is, if it\'s badly sealed, it will go boom.

[LukeTim]

Wonderful launch Luke.

I am envious, that you can use rockets so freely..

May I ask:

What grade of Rocket did you use? ie, the Black Powder cartridge grade?

Was that the basic Estes Launch Pad, or the bigger version?

Does the launch pad, come with some form of level, or adjusters, to help level it perfectly vertical?

An importantly will Patriot, launch again?

Hey, man. I\'m sorry, I could\'ve sworn I answered these questions the other day.

I used an Estes B4-4 Motor. It\'s an Estes Porta Pad II, which comes with all their launch sets. It\'s not a particularly great launch pad, though I\'ve had no experience of any others, it\'s not particularly easy to adjust and it\'s pretty basic really... but it does the job.

The Patriot will indeed launch again! I plan on Launching again next Sunday, when I should have a bigger audience. Last time it was just me and my brother.

[GWBBQ]

I also decided to get back into rocketry thanks to KSP. Here\'s my first rocket since high school. The perspective is a bit funny, the rocket is 18' long and my wrist most certainly isn\'t as fat as it looks in this picture.

The boosters are designed to fall away after burnout R7-style. I\'m not sure if I want to risk flying it without testing the attachment points, I might build a test rig and point it at the sand in the blast pit in my back yard (I was tired of reseeding scorched lawn after setting off firework so I built a blast pit.)

The difference between high explosives (like semtex) and other explosives (like gunpowder) can basically be summed up as this; if you put a low explosive into a tube with one end open, the pressure produced will just come out of the tube (and you\'ve got a rocket). If you put a high explosive into a tube, open ended or not, it\'ll explode.

High explosives detonate (blast front propagates faster than the speed of sound,) low explosives deflagrate (burn with a subsonic shock wave.) That said, Semtex and most plastic explosives will burn rather than detonating if ignited without the impact of a blasting cap.

[LukeTim]

I also decided to get back into rocketry thanks to KSP. Here\'s my first rocket since high school. The perspective is a bit funny, the rocket is 18' long and my wrist most certainly isn\'t as fat as it looks in this picture.

The boosters are designed to fall away after burnout R7-style. I\'m not sure if I want to risk flying it without testing the attachment points, I might build a test rig and point it at the sand in the blast pit in my back yard (I was tired of reseeding scorched lawn after setting off firework so I built a blast pit.)

High explosives detonate (blast front propagates faster than the speed of sound,) low explosives deflagrate (burn with a subsonic shock wave.) That said, Semtex and most plastic explosives will burn rather than detonating if ignited without the impact of a blasting cap.

Wait, how do the boosters fall away? And how is the main stage then ignited?

I love that design, man. Would love to see a video of it launching.

Also, I recently saw some plastic explosive which exploded when ignited using a traditional fuse and match...

[Vostok]

The boosters look like they\'re held in place with pin-and hoop straws, so that they fall out downwards, and rely on the acceleration of launch to hold them in place, until burnout and they just drop off.

[Seanoog]

The boosters look like they\'re held in place with pin-and hoop straws, so that they fall out downwards, and rely on the acceleration of launch to hold them in place, until burnout and they just drop off.

Exactly how I see them.

Perfect approach for adding More Boosters.

---

On further reading into N Ireland Fire Arm Law.

I believe N Ireland in covered under Main Land England interpritation of Rockets

So it may be totally legal to buy/store an fire Black Powerder Rockets + Hybrids.

However its completely illegal to mix our own..

(In fear, of hobbiests using there new found knowledge to make weapon grade explosives for Terrorists purposes.Which isn\'t good.)

However I am concernned why there is no Rocket Clubs.

I shall continue reading an researching, so I know its legal.

Dont fancy been fined or time, for a hobby/interest..

More to follow soon...

[GWBBQ]

Just like the folks above me said, once they burn out (and the main engine is still burning) the boosters will fall away due to gravity. It could be a challenge to make them fall away and make the parachutes deploy on time, but the whole thing cost maybe $15 and I\'m OK losing it as long as it doesn\'t hurt anyone.

[LukeTim]

Ahh, I see. That makes sense.

Is anyone here a member of a model rocketry club or anything? Know any good ones in the UK?

[OdinYggd]

This thread is making me miss my old rockets. Though I don\'t miss the one that got stuck on the launchpad. That one burned a hole clean through a 1/4' steel deflector plate using an A8-3 engine.

I used to have a small fleet of Estes brand model rockets built from kits, and would fly them somewhat regularly about my yard. Sadly the few surviving pictures of them are film prints, though some of these I\'ve found similar ones on google for reference images.

My favorite was the Viking, if I can find another kit I\'ll probably rebuild it.

But I also had an Alpha, Mosquito, Astrocam (This took pictures in flight, really fun), Skywinder (Rocket launch, autorotating helicopter recovery), Gnome (this always whistled like a bottle rocket for some reason), Longshot, Commanche3- a massive 3-stage that only ever flew the top two, and the Silver Comet- a craft that strongly resembled a 1960s scifi vessel that was quite fun to fly.

Perhaps I should dig through the attic and see if any of them survived. The prepackaged engines I used back then should still be available at the hobby shop, all I would have to do is rebuild my launch pad- more than 10 years sitting forgotten in the barn did some damage.

Also the pics above of the kit that drops the gliders- what is that called? I used to have something similar, it carried two gliders into the air on launch, and at ejection the main tube separated, dropping the gliders to circle the airfield while the main body returned via parachute with both halves dangling from it. The layout looks identical as do the relative sizes, you just haven\'t installed the wings on the gliders or the bottom half of the glider mounts.

[LaydeeDem]

This thread is making me miss my old rockets. Though I don\'t miss the one that got stuck on the launchpad. That one burned a hole clean through a 1/4' steel deflector plate using an A8-3 engine.

I used to have a small fleet of Estes brand model rockets built from kits, and would fly them somewhat regularly about my yard. Sadly the few surviving pictures of them are film prints, though some of these I\'ve found similar ones on google for reference images.

My favorite was the Viking, if I can find another kit I\'ll probably rebuild it.

But I also had an Alpha, Mosquito, Astrocam (This took pictures in flight, really fun), Skywinder (Rocket launch, autorotating helicopter recovery), Gnome (this always whistled like a bottle rocket for some reason), Longshot, Commanche3- a massive 3-stage that only ever flew the top two, and the Silver Comet- a craft that strongly resembled a 1960s scifi vessel that was quite fun to fly.

Perhaps I should dig through the attic and see if any of them survived. The prepackaged engines I used back then should still be available at the hobby shop, all I would have to do is rebuild my launch pad- more than 10 years sitting forgotten in the barn did some damage.

Also the pics above of the kit that drops the gliders- what is that called? I used to have something similar, it carried two gliders into the air on launch, and at ejection the main tube separated, dropping the gliders to circle the airfield while the main body returned via parachute with both halves dangling from it. The layout looks identical as do the relative sizes, you just haven\'t installed the wings on the gliders or the bottom half of the glider mounts.

Those ain\'t no gliders. They\'re boosters. 8)

Also, I decided to make a 'manned' capsule for my rocket. I\'ll post pics soon.

[ping111]

Just like LukeTim, my first rocket was the Estes Alpha III, with B6-4 engine. It was a great launch, but the wind carried it away and we lost it. I have an Estes Big Bertha, and I\'m going to try and build that today.

[GWBBQ]

Those ain\'t no gliders. They\'re boosters. 8)

What this guy said. I ordered a bunch of parts from Apogee Rockets and threw that together. In retrospect, I poured way too much lead shot into the nosecone for ballast and will probably need to replace it before it flies.

[Polecat Industries]

My first rocket was an Estes Sky Twister. Third launch, hit the ground hard from 650 feet. No chute. Small crater in the snow, and a basically obliterated body tube. Has not flown since.

[dogon11]

I forget what my first was called, but the second launch got it stuck in a tree... a branch over from someone else\'s pencil rocket.

[Polecat Industries]

Hey, Vostok, do those rockets you showed (minus the papercraft one) run on standard model engines or our own concoction?

[Vostok]

Hey, Vostok, do those rockets you showed (minus the papercraft one) run on standard model engines or our own concoction?

They run on my own pseudo-legal mixture of Potassium Nitrate and sugar. Which is why none of them have flown yet. Although, for no flights, a 30m height record is pretty good, I reckon... (height of Command Module after explosion)

[Wolvenhaven]

I used to do a lot of rockets in highschool. One of my favorite builds was a no-parachute glider which used the fins to come down at a 45 degree angle in a lazy spiral. I got yelled at several times by adults for making 'a ballistic missile' because they had never seen it work. It consisted of a full length BT-20 tube with 4 2' high basswood fins cut so that a 2' high BT-80 tube would fit around them and glued in place. C and D engines would get it up to several thousand feet and then you could watch it fly back down for a gentle landing. I know I have pictures of it somewhere but I can\'t find them. I also did the TSA rocketry competitions which required a lot of math and work, rocksim was a lifesaver for design testing. I miss flying them but it was too much work to get to decent launch sites around here, you\'d have to drive 3 hours just to get somewhere you could launch above 200ft and as a teenager that was difficult. When a friend told me about Kerbal I got addicted because it was like my childhood with rocksim only so much cooler.

[TouhouTorpedo]

Hmm a lot of people calling Estes units engines here. But they aren\'t really engines, they\'re single use motors.

The SEDS society at my university launched a pretty big one, about 2.5m long nearly 3km high. Its a nice piece of kit. Think it was using a Cessaroni motor, May have been an L class if I rememeber right.

[LukeTim]

Hmm a lot of people calling Estes units engines here. But they aren\'t really engines, they\'re single use motors.

The SEDS society at my university launched a pretty big one, about 2.5m long nearly 3km high. Its a nice piece of kit. Think it was using a Cessaroni motor, May have been an L class if I rememeber right.

There\'s a difference between motor and engine? I\'ve been using the two terms interchangeably.

[Wolvenhaven]

There\'s a difference between motor and engine? I\'ve been using the two terms interchangeably.

There is, but no one really cares about being that pedantic.

[Vostok]

I did have some pretty far out ideas myself for making a small sized rocket motor with an aerospike nozzle

Although with only a potters\' wheel and a kiln at my disposal for making ceramic pieces, It\'d be unlikely to happen to any kind of accuracy.

Although I do wonder, what\'s the lower size limit on rocket engines with liquid fuel? if there is one, that is?

[Wolvenhaven]

I did have some pretty far out ideas myself for making a small sized rocket motor with an aerospike nozzle

Although with only a potters\' wheel and a kiln at my disposal for making ceramic pieces, It\'d be unlikely to happen to any kind of accuracy.

Although I do wonder, what\'s the lower size limit on rocket engines with liquid fuel? if there is one, that is?

The smallest one I\'ve seen was about 2ft high and 4' diameter. The problem is they aren\'t really true liquid engines, they\'re hybrids, they use parafin wax and liquid oxygen. I don\'t know of any true liquid engines, I\'m sure they\'re out there but I haven\'t seen any.

[Vostok]

The smallest one I\'ve seen was about 2ft high and 4' diameter. The problem is they aren\'t really true liquid engines, they\'re hybrids, they use parafin wax and liquid oxygen. I don\'t know of any true liquid engines, I\'m sure they\'re out there but I haven\'t seen any.

I found some interesting sites with stuff about them, even kits!

It all seems very dangerous to me, I think I\'ll stick to soldering coins and fins to metal tubing.

Speaking of which, The MkIII bomb rocket is now under production.

After stripping all the old paint with acetone and a blowtorch, I\'ve set about soldering the main tube (a dubiously soldered 10p piece fit nicely to plug up the non-rockety end), in order to make it not explode this time, and I\'ve found a nice new way to deploy the parachute that doesn\'t rely as much on luck. I need to re-solder the engine mount bolts, since they mostly melted off in the last firing, and also re-make a new guide rail loop. Then, all that\'s required is a new CM, and a parachute. (and of course some paint, and a large '03' written on the side somewhere.