Thanks Thom, I just did a autopsy on a used K1450 motor. I think I will leave the stop in my next motors. The area where the two sections of PVC butt up against each other widened to about 1/16 inch. The heat of combustion did not appear to penetrate the coupling, but it might be better to leave it thicker here by leaving the shoulder in the coupling.
Nice. Any info on the grain dimensions other than you used 8 grains for a M-2400 We've built M and N sugar pvc motors and now working on an 'O-impulse' (we've already flown an 'O' sugar in an aluminum motor with steel nozzle. Have you fired or flown your 'M' motor?
My first motor was a M3000 in a schedule 80 pvc electrical conduit. Pressure rated pvc was not in stock and cost 3 times as much. Obviously all PVC is not the same! I use schedule 80 because of the 2.5 second burn. I ordered pressure rated pvc and reduced the nozzle exit from 3 inches to 2.65 inches. I keep my pressures at the low end, 307 psi for the M3000 motor and 259 psi for the M2400 motor. ua-cam.com/video/_X3uFq2epWo/v-deo.html
So by building the throat with the convergence and divergence. What percentage does this increase the speed or the efficiency of the rocket? Right now I am learning so I am building class 1 rockets.
I don't know if the converging part is that necessary, but the diverging cone accelerates the gasses to three times the velocity of the throat diameter without a diverging cone.
@@dariocardajoli6831 The gasses are flowing at the speed of sound through the throat area (choked flow). which is the maximum no matter what the pressure is. The gasses expand in the diverging part of the nozzle and accelerate to about three times the speed of sound. The diverging nozzle is very important to good performance,
I can't really say, I have entertained the thought of using a 10 pound fire extinguisher, An end burner would not work, it would have to have a core. PVC is the way to go in my opinion, I would not recommend making this type of motor.
I would have figure that if you used metal cases you could use higher pressure fuels and such without the risk of an explosion. I'm currently designing a system to vacuum cast sugar fuels to see if that will affect performance. And along side that was wanting to just use the metal as the body of the rocket too to save that much more weight.
Oh of course I'll be standing back! I will probably make some sort if makeshift bunker to hide in from cement block or something. My plan was having a nozzle of about two inches throat diameter. I might also try some dextrose based fuel.
Sorry, i mis spelled the name . It is Rockite. It sets in about 15 minutes and leftover in the bottom of a cup snaps like a ceramic tile.. I have used Durhams rockhard water putty, but I prefere Rockite. www.rockitecement.com
My first motor was made with schedule 80 electrical PVC conduit. I could not find pressure rated PVC in my city, and the cost was $50 vs $15. I figured PVC is all the same, right? Lesson learned, I salvaged about half of my rocket. The CATO occurred about one second into the 2.5 second burn. I estimate about 8 pounds of propellant fragmented and did not burn. Next version will launch in February. Here is the on board video of M3000 sorbitol motor ua-cam.com/video/_X3uFq2epWo/v-deo.html
I have two M2400 motors ready to fly. Wet season is here, just waiting for a clear wind free day. The rocket weighs about 70 pounds, max altitude should be about 4,000 feet. I expect my first flight to fly nicely, but my second motor is made from a bent piece of 3 inch schedule 80 PVC. I guess I will fly this motor, but either the top of the motor will be offset from center by 3/4 inch or the nozzle will be off centerline by a few degrees. I can't realy believe that it will fly straight.
I have a newer version, it plays at a faster speed with more watching and less reading. ua-cam.com/video/3NcNwrqLl4o/v-deo.html&lc=z22rjjzblyqjdndssacdp43b0wa3kjpugwbvxvom001w03c010c.1546287354826350
Do NOT do this! I'm an engineer (BS, MS, PhD) and a registered Professional Engineer (California - Mechanical, mainly for pressure vessels) . Making ANYTHING that contains gas pressure using PVC is incredibly dangerous. This is why shop air systems (at least safe ones) do not use PVC. For rocketry, PVC is a really, really bad choice of materials. Motor pressures can go up to 3500psi inside high performance engines. Sugar motors range in the 560-750 psi range. Maximum safe working pressure for (for example) 3 inch PVC is 260 or 370 psi (schedule 40 and 80 respectively). If you don't want to believe me, at least trust experts. If you want to launch at any Tripoli sponsored launch, they shouldn't let you if you are using a PVC case. From section 10-10.2 of the Tripoli Safety Code: "Non-Metallic cases shall not be made of brittle materials which may rupture into sharp shards, SUCH AS PVC". (I added the emphasis). Paper tubes, fiberglass, or ductile aluminum (such as 6061 in the proper heat treat state) are all fine choices. Use PVC and you are basically making a potential grenade. DON'T DO THIS!
My three inch PVC sorbitol motor operates at a constant 350 PSI for 2.6 seconds. I don't try for maximum performance and have only experienced one motor failure due to using three inch PVC electrical conduit instead of pressure rated PVC. I wouldn't like to be standing next to it, but I am always about 300 feet away from the launch. All of the pieces fell within a 200 foot circle, they don't travel very far ua-cam.com/video/jZHfL3lX5jc/v-deo.html
If you have done this, then it doesn't matter that you are good or bad in communication, you should try again definitely it will rock and dont forget to keep background music.
I was all excited to watch your video until I realized you're not going to say a single word and I really don't like that so thank you anyway and goodbye
Great video.
More specifics on grain count, dimensions, nozzle angles, etc would allow for easier replication.
Thanks for the video!
From scratch ! Yes.
Good Hands.... Great Flight...
I really appreciate you sharing your work through these videos. Thank you, they are so informative and thoughtful.
What video? It's just still pictures and text.
Love the videos Gary. Can't wait to see it go woooosh.
It flew March 31,2018 the flight went well, but the landing was bad. one fin broke but it will be repaired.
ua-cam.com/video/NYmj-KYKH78/v-deo.html
I flew it yesterday, everything worked. ua-cam.com/video/t1M_WC4t5k8/v-deo.html
NYC Gary... You are too familiar you are not like the other...
They make a 3" repair coupling with no stop inside.
Thanks Thom, I just did a autopsy on a used K1450 motor. I think I will leave the stop in my next motors. The area where the two sections of PVC butt up against each other widened to about 1/16 inch. The heat of combustion did not appear to penetrate the coupling, but it might be better to leave it thicker here by leaving the shoulder in the coupling.
ckecks video upload date to see if it's 2007 or 2008
HOLY SHIT, 2017 ? but I thougnt the YT editor was dead ?
Nice. Any info on the grain dimensions other than you used 8 grains for a M-2400
We've built M and N sugar pvc motors and now working on an 'O-impulse' (we've already flown an 'O' sugar in an aluminum motor with steel nozzle.
Have you fired or flown your 'M' motor?
My first motor was a M3000 in a schedule 80 pvc electrical conduit. Pressure rated pvc was not in stock and cost 3 times as much. Obviously all PVC is not the same! I use schedule 80 because of the 2.5 second burn. I ordered pressure rated pvc and reduced the nozzle exit from 3 inches to 2.65 inches. I keep my pressures at the low end, 307 psi for the M3000 motor and 259 psi for the M2400 motor. ua-cam.com/video/_X3uFq2epWo/v-deo.html
So by building the throat with the convergence and divergence. What percentage does this increase the speed or the efficiency of the rocket? Right now I am learning so I am building class 1 rockets.
I don't know if the converging part is that necessary, but the diverging cone accelerates the gasses to three times the velocity of the throat diameter without a diverging cone.
@@hs72comm so the gasses are already sonic when entering the diverging part ?
@@dariocardajoli6831 The gasses are flowing at the speed of sound through the throat area (choked flow). which is the maximum no matter what the pressure is. The gasses expand in the diverging part of the nozzle and accelerate to about three times the speed of sound. The diverging nozzle is very important to good performance,
Say I wanted to build a motor out of a few of those helium tanks you see at birthday parties. What would that be classed as?
I can't really say, I have entertained the thought of using a 10 pound fire extinguisher, An end burner would not work, it would have to have a core. PVC is the way to go in my opinion, I would not recommend making this type of motor.
I would have figure that if you used metal cases you could use higher pressure fuels and such without the risk of an explosion. I'm currently designing a system to vacuum cast sugar fuels to see if that will affect performance. And along side that was wanting to just use the metal as the body of the rocket too to save that much more weight.
Oh of course I'll be standing back! I will probably make some sort if makeshift bunker to hide in from cement block or something. My plan was having a nozzle of about two inches throat diameter. I might also try some dextrose based fuel.
Sounds good, I usually size my nozzles between one third and one half of the motor ID. Good luck, it certainly will handle a lot of pressure.
That would be classified as entertainment.
Rocktite? Or locktite? Never heard of rocktite
Sorry, i mis spelled the name . It is Rockite. It sets in about 15 minutes and leftover in the bottom of a cup snaps like a ceramic tile.. I have used Durhams rockhard water putty, but I prefere Rockite. www.rockitecement.com
There is no video here. It's just still pictures and text that's hard to follow. Why bother?
Where's the video of this monster firing?
My first motor was made with schedule 80 electrical PVC conduit. I could not find pressure rated PVC in my city, and the cost was $50 vs $15. I figured PVC is all the same, right? Lesson learned, I salvaged about half of my rocket. The CATO occurred about one second into the 2.5 second burn. I estimate about 8 pounds of propellant fragmented and did not burn. Next version will launch in February. Here is the on board video of M3000 sorbitol motor ua-cam.com/video/_X3uFq2epWo/v-deo.html
It flew March 31,2018 the flight went well, but the landing was bad. one fin broke but it will be repaired.
ua-cam.com/video/NYmj-KYKH78/v-deo.html
I flew it yesterday, everything worked. ua-cam.com/video/t1M_WC4t5k8/v-deo.html
So this is what happens whencs plumber tinkers 😄
Gary. Any update on this motor?
I have two M2400 motors ready to fly. Wet season is here, just waiting for a clear wind free day. The rocket weighs about 70 pounds, max altitude should be about 4,000 feet. I expect my first flight to fly nicely, but my second motor is made from a bent piece of 3 inch schedule 80 PVC. I guess I will fly this motor, but either the top of the motor will be offset from center by 3/4 inch or the nozzle will be off centerline by a few degrees. I can't realy believe that it will fly straight.
Be sure to record it!
It flew March 31,2018 the flight went well, but the landing was bad. one fin broke but it will be repaired.
ua-cam.com/video/NYmj-KYKH78/v-deo.html
@@b5a5m5 I flew it yesterday, everything worked. ua-cam.com/video/t1M_WC4t5k8/v-deo.html
more pictures. at least one for every time you make me READ, please.
I have a newer version, it plays at a faster speed with more watching and less reading. ua-cam.com/video/3NcNwrqLl4o/v-deo.html&lc=z22rjjzblyqjdndssacdp43b0wa3kjpugwbvxvom001w03c010c.1546287354826350
WHY DIDN'T YOU SHOW IT IN ACTION????
it flew about a year ago with wrong kind of PVC for motor. ua-cam.com/video/jZHfL3lX5jc/v-deo.html It will fly again very shortly.
It flew March 31,2018 the flight went well, but the landing was bad. one fin broke but it will be repaired.
ua-cam.com/video/NYmj-KYKH78/v-deo.html
I flew it yesterday, everything worked. ua-cam.com/video/t1M_WC4t5k8/v-deo.html
Do NOT do this! I'm an engineer (BS, MS, PhD) and a registered Professional Engineer (California - Mechanical, mainly for pressure vessels) . Making ANYTHING that contains gas pressure using PVC is incredibly dangerous. This is why shop air systems (at least safe ones) do not use PVC. For rocketry, PVC is a really, really bad choice of materials. Motor pressures can go up to 3500psi inside high performance engines. Sugar motors range in the 560-750 psi range. Maximum safe working pressure for (for example) 3 inch PVC is 260 or 370 psi (schedule 40 and 80 respectively). If you don't want to believe me, at least trust experts. If you want to launch at any Tripoli sponsored launch, they shouldn't let you if you are using a PVC case. From section 10-10.2 of the Tripoli Safety Code: "Non-Metallic cases shall not be made of brittle materials which may rupture into sharp shards, SUCH AS PVC". (I added the emphasis). Paper tubes, fiberglass, or ductile aluminum (such as 6061 in the proper heat treat state) are all fine choices. Use PVC and you are basically making a potential grenade. DON'T DO THIS!
My three inch PVC sorbitol motor operates at a constant 350 PSI for 2.6 seconds. I don't try for maximum performance and have only experienced one motor failure due to using three inch PVC electrical conduit instead of pressure rated PVC. I wouldn't like to be standing next to it, but I am always about 300 feet away from the launch. All of the pieces fell within a 200 foot circle, they don't travel very far ua-cam.com/video/jZHfL3lX5jc/v-deo.html
use video and narration for more effective communication.
I tried that on my earlier videos, I am not a very good communicator.
If you have done this, then it doesn't matter that you are good or bad in communication, you should try again definitely it will rock and dont forget to keep background music.
😍ههههههه كويس الحمد لله
@Iraqi.Basra ١٢سنة ملحد that escalated quickly!
Kamprettt.. Lieur macana geh.. Tulisan jeung gambarna nu jeben geh dia
Excuse me for not speaking, but I don't think you would understand that either
Un peu complique ils n en vendent pas des tout fini
I was all excited to watch your video until I realized you're not going to say a single word and I really don't like that so thank you anyway and goodbye
If you watch some of my earlier videos you will see why I do not narrate the video. I am not a public speaker, and I am a worse narrator.
I flew it yesterday, everything worked. ua-cam.com/video/t1M_WC4t5k8/v-deo.html Note for you, 2/3 of the video has a sound track
Gorgeous