My First level one Rocket

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kcobbva

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I finally decided to build the Madcow Torrent for my first level 1 attempt. I'm getting closer to completion and got the ebay wired up tonight. Thankfully the pin slot worked and it slid into place shutting off the PerfectFlight altimeter, after sealing the bay. (After gluing the aft bulkhead in place I finally test fit one more time and found I was WAY OFF from my hole, and I had TESTED that :bang:. (I put the sled in backwards...thank goodness :D)! When I turned it, the hole lined right up with the brass tube and switch. Thanks again to KenECoyote and rharshberger for answering questions and pointing me to the brass rods/tubes. Still got a ways to go, but it's sure fun again!

Sorry I cannot seem to rotate these. (btw, the tube isn't rotated properly with the kids picture. The pin isn't in line with the rail guides normally)
WP_20151118_21_21_44_Raw.jpgWP_20151118_21_42_15_Raw.jpg
 
Nice! The Torrent is a popular beasty for L1 certifications, and with good reason. Good on you for building with the altimeter and all from the start. Even if you cert motor eject, you'll want to get aggressive with that rocket one of these days (soon). Always good to have a fine launch and recovery crew as well.

Enjoy the rest of the build, and good luck on the cert when the time comes.
 
Nice! The Torrent is a popular beasty for L1 certifications, and with good reason. Good on you for building with the altimeter and all from the start. Even if you cert motor eject, you'll want to get aggressive with that rocket one of these days (soon). Always good to have a fine launch and recovery crew as well.

Enjoy the rest of the build, and good luck on the cert when the time comes.

Thanks very much. I don't want to motor cert at the start. I flew plenty of rockets up to the point I had to stop about 10 years ago, due to little kids and life. I always wanted to do electronic based deployment, so I'm going for gold. Whether I pass or not, at least I'm staying true to that desire. (I'm being as diligent as I can in the details to ensure it works the first time, to the best of my ability). Feels like being a kid again, and that has been fun!
 
Thanks very much. I don't want to motor cert at the start. I flew plenty of rockets up to the point I had to stop about 10 years ago, due to little kids and life. I always wanted to do electronic based deployment, so I'm going for gold. Whether I pass or not, at least I'm staying true to that desire. (I'm being as diligent as I can in the details to ensure it works the first time, to the best of my ability). Feels like being a kid again, and that has been fun!

Cert what and how you want to fly, I like it. In general I trust my electronics way more than a motor ejection charge anyway. Are you going to have to wait for spring, or do you have winter launches? In any event, good luck.
 
Nice choice. I've seen this fly on H's and J's. I'm sure you'll get some mileage out of it!
 
Cert what and how you want to fly, I like it. In general I trust my electronics way more than a motor ejection charge anyway. Are you going to have to wait for spring, or do you have winter launches? In any event, good luck.

I wish I could just jump out and do it, but I haven't even had a chance to join my local club yet, NOVAAR, because I always seem to have a family or company commitment on the night they meet. Took me 4 or 5 months between the time I joined NAR and bought the rockets, but something always comes up. Regardless, when I finally get all my junk in order, the rocket should be ready to fly. I might even have my Madcow Level-2 rocket built by the time this happens as it's sitting in a box by my workbench for my level 2 attempt. Haven't worked with fiberglass tubes before, so I'm wondering if I should pickup their 2" Black Brandt and work through that first. I don't see a whole lot of extra effort other than ensuring parts are prepared properly before epoxying in place (and using stronger epoxy than the bob smith brand I'm used to...something like West System or Aeropoxy - I'm all ears if anyone has suggestions there). Anyway, this kid is in the candy store having a blast for now.. unfortunately after the kids go down and well after I should be going down at night. :)
 
I have two short people, so I know the waiting until you should be asleep to build issue also. As for epoxy, I use Aeropoxy due to the testing of John Coker (linked below). I really like Aeropoxy, but it does take quite awhile to cure. It is just thin enough to flow slowly also, so if you are using it anywhere gravity could get involved a little milled fiberglass (can get at a hobby shop) added in really makes it stay put, and strengthens the joint also. In truth, you would probably be fine with the Bob Smith 5 min for all but extreme conditions, > Mach 2, HARD landings, etc. I switched to Aeropoxy when I started doing larger projects and was simply using more epoxy. Per oz it is very comparable in price with hobby grade epoxies, so it wasn't really a cost increase for me to move up to a better product. As for a 2" test kit, it never hurts to have one more rocket. :wink:

https://www.jcrocket.com/adhesives.shtml
 
MDRA has a launch Saturday and Sunday at the Higgs Farm on Maryland's Eastern Shore. $25 to join the club for a year, $10 to launch for the weekend. Lots of people there who can certify you. Come on out and git 'er done!
 
MDRA has a launch Saturday and Sunday at the Higgs Farm on Maryland's Eastern Shore. $25 to join the club for a year, $10 to launch for the weekend. Lots of people there who can certify you. Come on out and git 'er done!
Wish I could get out there, but it's about a 2 hour ride. Will have to take some planning and a hall pass when I can. Eventually I do want to as I understand you guys have a higher ceiling waiver than is out at The Plains. (ie. I know that the level-2 has the ability to go much higher, and after cert, I want to push that limit!) Looking forward to that day!
 
I have two short people, so I know the waiting until you should be asleep to build issue also. As for epoxy, I use Aeropoxy due to the testing of John Coker (linked below). I really like Aeropoxy, but it does take quite awhile to cure. It is just thin enough to flow slowly also, so if you are using it anywhere gravity could get involved a little milled fiberglass (can get at a hobby shop) added in really makes it stay put, and strengthens the joint also. In truth, you would probably be fine with the Bob Smith 5 min for all but extreme conditions, > Mach 2, HARD landings, etc. I switched to Aeropoxy when I started doing larger projects and was simply using more epoxy. Per oz it is very comparable in price with hobby grade epoxies, so it wasn't really a cost increase for me to move up to a better product. As for a 2" test kit, it never hurts to have one more rocket. :wink:

https://www.jcrocket.com/adhesives.shtml

Thanks again! That site is exactly where I got pointed toward those two options of epoxy. I also appreciate the tip of the milled fiberglass addition! While it may be a little overkill initially, it's also the pursuit of knowledge and understanding driving me to use that on the next rocket.
 
I finally decided to build the Madcow Torrent for my first level 1 attempt. I'm getting closer to completion and got the ebay wired up tonight. Thankfully the pin slot worked and it slid into place shutting off the PerfectFlight altimeter, after sealing the bay. (After gluing the aft bulkhead in place I finally test fit one more time and found I was WAY OFF from my hole, and I had TESTED that :bang:. (I put the sled in backwards...thank goodness :D)! When I turned it, the hole lined right up with the brass tube and switch. Thanks again to KenECoyote and rharshberger for answering questions and pointing me to the brass rods/tubes. Still got a ways to go, but it's sure fun again!

Sorry I cannot seem to rotate these. (btw, the tube isn't rotated properly with the kids picture. The pin isn't in line with the rail guides normally)
View attachment 276345View attachment 276346

Going with electronics with your level one...going for the gusto.

A lot of folks keep it real simple to get past the first hurdle...more power to ya!
 
I finally decided to build the Madcow Torrent for my first level 1 attempt. I'm getting closer to completion and got the ebay wired up tonight. Thankfully the pin slot worked and it slid into place shutting off the PerfectFlight altimeter, after sealing the bay. (After gluing the aft bulkhead in place I finally test fit one more time and found I was WAY OFF from my hole, and I had TESTED that :bang:. (I put the sled in backwards...thank goodness :D)! When I turned it, the hole lined right up with the brass tube and switch. Thanks again to KenECoyote and rharshberger for answering questions and pointing me to the brass rods/tubes. Still got a ways to go, but it's sure fun again!

Sorry I cannot seem to rotate these. (btw, the tube isn't rotated properly with the kids picture. The pin isn't in line with the rail guides normally)

Wow, looks great! I also like your planning and building...seems like you research and plan before building and plan ahead for what you'll do later and I usually do the same. Great looking rocket and safety flag! I also love your "it's sure fun again!" statement. Really covers why I enjoy rocketry so much. :grin:

Also try writing "UP" on the sled...may save you a bit of a scare. :wink:
 
Hey all. Question. So should I put 3 or 4 shear pins on the Torrent? The upper tube is extended from 12" to 19". I believe I just have to account for the added volume when determining the amount of black powder, the same as if it was 12", so the pins shouldn't have anything to do with the length. However, I'm curious what the school of thought is on the shear pins. They are #2-56 pins. Thanks in advance.
 
Wow, looks great! I also like your planning and building...seems like you research and plan before building and plan ahead for what you'll do later and I usually do the same. Great looking rocket and safety flag! I also love your "it's sure fun again!" statement. Really covers why I enjoy rocketry so much. :grin:

Also try writing "UP" on the sled...may save you a bit of a scare. :wink:

What a GREAT idea! Amazing how "simple" things can be so hard to think of!!
 
Couldn't add the pic a bit ago. Thanks again for the pointer!View attachment 276402

You have "UP" pointing sideways!!! :grin:

Here's a quick tip to rotate the pics. Assuming you're using Windows, go to the picture file in Explorer and double click on it and it should open in Windows Photo Viewer. There you will see rotation arrows at the bottom menu, just hit either one the correct number of times and close the viewer (or click on a "Next" button to view the next picture) and it will autosave for you. Then post/link/etc. Takes seconds. :)

Also I'd recommend that you put a block on the other side of the battery or drill holes to add a second zip-tie around the other way since the battery may slip out on boost. Simple addition that can save you a lot of headache. YMMV
 
Hey all. Question. So should I put 3 or 4 shear pins on the Torrent? The upper tube is extended from 12" to 19". I believe I just have to account for the added volume when determining the amount of black powder, the same as if it was 12", so the pins shouldn't have anything to do with the length. However, I'm curious what the school of thought is on the shear pins. They are #2-56 pins. Thanks in advance.

Here's a site for bp charge calculation which also notes the number of pins:
https://www.rimworld.com/nassarocketry/tools/chargecalc/index.html

You can also do a search for a build on the same rocket to see how many pins the other person used.
 
ALL my future HPR builds will use shear pins when the airframe permits, I like the consistency of knowing its going to work the same every. No estimating that my friction fit is the "same" as last go around.
 
I use the same amount of shear pins as fins. I place them in line with the fins. I do this because asymetry makes me crazy, not really for scientific reasons. As long as you ground test with the same configuration you will fly all will be well.
 
Thanks guys. I really appreciate all the helpful info. I've been watching a youtube video and asked him as he did place sheer pins in his torrent. It's a great guide on top of the Apogee videos and your expertise!! [video=youtube;HLvo2MFzDPk]https://www.youtube.com/watch?v=HLvo2MFzDPk[/video]
 
I use the same amount of shear pins as fins. I place them in line with the fins. I do this because asymetry makes me crazy, not really for scientific reasons. As long as you ground test with the same configuration you will fly all will be well.

+1 the symmetry
 
Here's a couple of things I do differently with shear pins which works for me, so I'd like to pass on:

1) Most available shear pins are just flat head. This drives me crazy since the pin is flexy and I kept having issue with the screwdriver slipping off and hitting the nicely finished rocket. Since then I've found phillips head screws (also slotted for flathead as well) and they are almost identical and work very well...always ground test first. On Amazon for $8 for 100 (different lengths available):
https://www.amazon.com/gp/product/B001GHKQX2/?tag=skimlinks_replacement-20

2) I thread the outer hole as shown in your video; however I drill a slightly bigger hole in the bay. This way it's easier alignment (much easier just seeing the inner hole, lining up and screwing it in than lining up two 2-56 tapped holes and trying a few times to screw in that last one or two. Also the screw head stays on the outer rocket so there's no littering and the other part can fall off inside the bay (make sure you don't have anything that the little nylon pins will mess up...unlikely, but each bay is different) and that makes it also simpler to remove the broken off part rather than using pliers to twist them off on the inside, etc.

Just my :2:. :)
 
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Here's a couple of things I do differently with shear pins which works for me, so I'd like to pass on:

1) Most available shear pins are just flat head. This drives me crazy since the pin is flexy and I kept having issue with the screwdriver slipping off and hitting the nicely finished rocket. Since then I've found phillips head screws (also slotted for flathead as well) and they are almost identical and work very well...always ground test first. On Amazon for $8 for 100 (different lengths available):
https://www.amazon.com/gp/product/B001GHKQX2/?tag=skimlinks_replacement-20

2) I thread the outer hole as shown in your video; however I drill a slightly bigger hole in the bay. This way it's easier alignment (much easier just seeing the inner hole, lining up and screwing it in than lining up two 2-56 tapped holes and trying a few times to screw in that last one or two. Also the screw head stays on the outer rocket so there's no littering and the other part can fall off inside the bay (make sure you don't have anything that the little nylon pins will mess up...unlikely, but each bay is different) and that makes it also simpler to remove the broken off part rather than using pliers to twist them off on the inside, etc.

Just my :2:. :)

+1 same techniques I use.
 
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Ok so the Pop Rivet holes have been drilled and the Shear Pin holes drilled and tapped. Went with three lined up with the fins - great advice! The tubes were lightly sanded and thin CA applied. Getting down to the BEST part of building a rocket, pinewood derby car, what have you... Sanding. Followed by paint choices. Speaking of paint, has anyone tried the Plutonium Paint line? From some previous research looks like good drying time and good coverage with less coats, but sellers often glamorize products. I prefer first hand knowledge or at least a few reviews that seem to agree with one another.

Spent the rest of the night testing the StratologgerCF in my vacuum chamber with a Jolly Logic 3 also in the chamber and comparing data. Pretty darn close apogee wise and the launch and recovery patterns look dead on. Guess I'm happy with those results; so I'll put it away so I don't break it!
 
Filling spirals and tube sanding done. Now waiting on the camera holder off Etsy before painting the primer. Again, anyone familiar with the Plutonium Paint line?
 
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