My level two cert rocket

[grouch]

Looks like fun. Good luck with the cert!

 

[bandman444]

I wonder how long till ROC gets rid of their one 1/2"rod.

Whens the cert?

Bryce

 

[edwinshap1]

I wonder how long till ROC gets rid of their one 1/2"rod.

Whens the cert?

Bryce

saturday and they have like 4 1/2" rods they may or may not replace the rods when they become unusable, but they have a bunch of em as of now

 

[UPscaler]

it's a 1/2" LL hole. spaced it far enough away from the main body that i wouldn't have any issue as far as the spokes, and most of the weight is right in the saucer anyway. i can use upto a 17" long motor, so a 54/1706, or a pro54 4grain. don't really intend to go much over that in thrust, but it's definitely strong enough

K185




Braden

 

[edwinshap1]

K185




Braden

burn tapers off to long. The motor will still be burning while facing down, so the ejection will happen far far too close to the ground for comfort.

only safe longburn is either the K270W or K300, both of which are really long.

 

[edwinshap1]

So i failed my level 2. aced the written exam, cuz u know...it was soo hard after memorizing the practice test, but at launch the rocket experienced a weird phenomena...crappy chinese made plastic nose cone failure. The NC eyelet broke at ejection and it separated, disallowing me to gain my level 2 cert. i could've just epoxied it one and tried again, but i think one 3 second money burn is enough for one day, so i've put this rocket on the back burner til i devise a fool proof (well almost fool proof) way of keeping it on

 

[daveyfire]

Oh hey, that's me in the blue shirt.

 

[edwinshap1]

Oh hey, that's me in the blue shirt.

wow i love this shot, can you email the original to me @[email protected]? thanks

 

[terryg]

One easy way to prevent this type of failure is to drill two holes into the base of the nose cone (as far apart as practical) and run a loop of high strength kevlar thru the openings and attach the quick link to it.

 

[edwinshap1]

One easy way to prevent this type of failure is to drill two holes into the base of the nose cone (as far apart as practical) and run a loop of high strength kevlar thru the openings and attach the quick link to it.

i didn't quick link, i just knoted it. does anyone know a good ahesive to use that'll attach kevlar to plastic? i just want to have it so well attached that it'll never come off.

 

[o1d_dude]

What terryg said.

Drill two holes in the bottom of the nosecone and pull the recovery harness through. Secure with a bowline knot.

Not quite as easy to remove as a quick link but I use the quick link to attach my chute to the recovery harness anyway. Not the nosecone.

 

[gdjsky01]

Not having followed this too closely... I should have... sorry... :bangpan:

Cut the tube. Screw the nose cone into the cut piece. Take a normal ply bulkhead, add a large eyebolt, fender washers and nuts. Epoxy in a coupler with the bulkhead in the other end of the cut piece. Done. Oui?

As as side benefit you have a (very?) small payload bay.

 

[edwinshap1]

Not having followed this too closely... I should have... sorry... :bangpan:

Cut the tube. Screw the nose cone into the cut piece. Take a normal ply bulkhead, add a large eyebolt, fender washers and nuts. Epoxy in a coupler with the bulkhead in the other end of the cut piece. Done. Oui?

As as side benefit you have a (very?) small payload bay.

ooh jeff i do like this idea

thanks for idea, but hmm, now i need a coupler tube XD

i had to do a small repair to the base of the rocket because what most people don't see is that after the thrust phase, the motor burns the phenolic for a good bit, and well...my rocket didn't coast upwards for more than half a second, so the unglassed foamboard got messed up. i mixed up a batch of jb weld and smeared it on the exposed foam portion. once that's hard i'll take a pic of the nosecone and what i did with it.

i drilled 4 holes through the base part of it as far to the edges as i could go, and i looped the kevlar through that. i think that'll be enough, but if people still think it's iffy i'll order a coupler piece

 

[edwinshap1]

So after my unsuccessful L2 due to a terrible plastic eyelet, i've made an "innovative" redesign. I drilled 4 holes around the side, and i intend to run the shock cord through all 4 holes and then tie it off.

I figure that if any of them break they'll all break, but i also figure that the plastic is thick enough that it'll be okay. anyone have any more solid ideas?

 

[Handeman]

So after my unsuccessful L2 due to a terrible plastic eyelet, i've made an "innovative" redesign. I drilled 4 holes around the side, and i intend to run the shock cord through all 4 holes and then tie it off.

I figure that if any of them break they'll all break, but i also figure that the plastic is thick enough that it'll be okay. anyone have any more solid ideas?

My first L2 attempt was also unsuccessful for the same reason. I had another rocket with the right sized nose cone so the second attempt that day worked just fine. I think the problem I had was two fold. The plastic loop was smaller then what I was used to using on my Binder Design rocket so I trusted it. I also used more powder then I use now.

I just cut two holes in the nose cone and they worked fine. As long as you don't "blow it up" with the ejection charge, it should work just fine.

 

[edwinshap1]

ah, so drilling was a good choice, thanks

and actually because of the extreme stability of this rocket, i could've flown it again without a nosecone, but i didn't want to burn 220 bucks in one day so i just launched my L1 rocket

 

[edwinshap1]

Level 2 complete on a K513 FJ. I'd like to thank Jack Garibaldi of Whats Up Hobbies for loaning me a case and having every motor i could possibly choose from in his trailer.

by the way, do not use blackjack motors on saucers, the bottom of my saucer was white...now it's a nice dark grey...

Well, time to send in my cert paperwork. I'll upload the vid i took of it on the rocket, and the pics/vids that people will upload of the flight.

I highly recommend building a saucer for your level 2. It keeps it very low and slow, which keeps the smoke nice and thick, and creates an awesome pressure effect for the kids to watch

 

[gdjsky01]

Congrats!!! It was an excellent flight!
:clap::clap::clap::clap:
:wave:

But your friend had some crappy happ'ns oui?

 

[stealth6]

Concerning the "drilling two holes in nosecone base and looping harness/cord through them" method:

I had a recent failure with this method. 2.5" diameter, LOC plastic cone, kevlar shock cord, motor ejection (AT 29mm F motor). Due to a couple of reasons, the rocket turned earthward way too early, and the ejection delay was way too long - the result was a rocket that was coming in VERY ballistic. The ejection charge kicked about 30' from the ground, with the rocket pointing down and coming in fast. The cord just ripped right through that base, and the nosecone kept right on going. Fortunately, I don't tie my chute to the cone itself, but rather to a loop in the shock cord a few inches down. So the chute deployed and saved the rest of the rocket (mostly) from any serious damage - a pretty healthy zipper, but that can be repaired. The cone is history.

I'm not sure that cutting off the cone's base and installing an actual bulkhead to attach the cord to would have helped in this situation, but I'm leaning toward this method more for future builds.

s6

 

[edwinshap1]

Congrats!!! It was an excellent flight!
:clap::clap::clap::clap:
:wave:

But your friend had some crappy happ'ns oui?

yeah bryce got 4 or so grams of black powder to his chest and such. He's okay though, cept that hes got an L851 he'll have to hold on to for a month or 2. perfectflite mawd had some capacitor issues or something (my guess).

i was more concerned with the 7 people out at that airstart rocket. two young girls who had no business standing near the nozzles of a rocket. one had to go to the hospital for possible burns, and the other was deafened for a few minutes by the exhaust noise.

A J401FJ ignited when the perfectflite ignited while supposedly shunted...

but yeah, time to upload my on rocket vid

 

[gdjsky01]

yeah bryce got 4 or so grams of black powder to his chest and such. He's okay though, cept that hes got an L851 he'll have to hold on to for a month or 2. perfectflite mawd had some capacitor issues or something (my guess).

i was more concerned with the 7 people out at that airstart rocket. two young girls who had no business standing near the nozzles of a rocket. one had to go to the hospital for possible burns, and the other was deafened for a few minutes by the exhaust noise.

A J401FJ ignited when the perfectflite ignited while supposedly shunted...

but yeah, time to upload my on rocket vid

People bring there kids out constantly. One person, surveying the whole f'in flight line AND launching, AND tracking rockets can not enforce what you just said. I had a spotter and many many times I was interrupted by him to point something out to me. That was awesome and as it should be. LCO should never be a lonely job.

I am always leery of someone blaming electronics... not that they don't fail, but more often than not, its a systematic error in handling.

 

[edwinshap1]

bryce's electronic were definitely at fault. i looked at his wiring setup and there was no way for those wires to ground or spark. he wasn't even touching the wires when it blew.

the other rocket, however, i'm less convinced on.

but thats not the point of this thread.

if anyone's got pics/vids of my successful (abiet "very very low and slow") i'd love to see them. I got a video posted to my facebook page, but i don't know how to post it externally.

 

[jeffgeraci]

if anyone's got pics/vids of my successful (abiet "very very low and slow") i'd love to see them. I got a video posted to my facebook page, but i don't know how to post it externally.

Congrats again Jared, that was a great flight. Too bad for anyone who missed it, and I hope you can get a vid on here soon. The way the exhaust "rippled" behind the octagon was keeeeewl as hell!! You've set the L2 bar pretty high pal!

 

[edwinshap1]

Congrats again Jared, that was a great flight. Too bad for anyone who missed it, and I hope you can get a vid on here soon. The way the exhaust "rippled" behind the octagon was keeeeewl as hell!! You've set the L2 bar pretty high pal!

actually, haven't i set the bar pretty... LOW

someone did upload a video to facebook, but i can't create an external link to the video

my favorite part about it is that it took a moment for the rocket to actually start moving, so theres a big poof of jet black smoke all around it before it starts. i need to add some lights and night launch it on a sparky

 

[gdjsky01]

This one here?

I'll delete the post if this is wrong.


BTW: One very popular reason for charges going off is people screwing up pos and neg on the battery or on the switch.

Do that on a G-Whiz and POOF!

 

[edwinshap1]

This one here?

I'll delete the post if this is wrong.


BTW: One very popular reason for charges going off is people screwing up pos and neg on the battery or on the switch.

Do that on a G-Whiz and POOF!

ah yes perfect, thanks for the link. and i hadn't thought to check for that when the charge went off. there was another live charge and i just wanted to get it safed. i'll ask bryce, but i think the MAWD has a safety feature for wire switching.

 

[RocketRob]

I have done this a few times and it works very well so far. last launch I had a 38mm 6 grain case in the rocket and it was pushing out my nose cone 1/4 inch since the case was so long. So only the chute and lines were between the Nose cone base, so there was a lot of force on that one area and it was just fine!

One easy way to prevent this type of failure is to drill two holes into the base of the nose cone (as far apart as practical) and run a loop of high strength kevlar thru the openings and attach the quick link to it.

 

[tstone]

I'm not creating a build thread for this one because i'm making a pretty much exact replica of this
https://www.rocketrytoday.com/octagon.html

but the BT is 32" and there's a nosecone and chute. The longest motor that i'll be able to fly is a 17" of any type.

It has a 54mm aeropack retainer, and I intend to fly it on a K540 MS from aerotech.

i need names for this rocket, any and all suggestions, but I do prefer ironic or punny names

I think you should glue some model chain link fence around the perimeter, and glue some WWF wrestling action figures on top of it.