Just finished my first HPR kit

[Elapid]

i like it!
it is a USR Sonic 3100 Phase Two.
I just need to put a parachute in it and stuff a motor in!
wooWHOO!

it is a 54mm native mount and i got the 29mm mounts and 3x 24mm mounts with it so i can use a variety of motors in it.

here's a pic of it (yeah that's me.)

 

[BlueNinja]

WOW!

I didn't think it was so big! thought it was like a LMR kit. That's awesome. What will you be flying it on for the first flight?

well, I made it-

POST 1000!!!

 

[Austin]

Excellent job man...that model looks soooo cool...definitely post a launch report with tons of pics!!!

Nice Job,

Carl

 

[lalligood]

Elapid,

WOW. Great lookin' bird y'got there! Please keep us up to date on it when you get a chance to put it up in the air. And if you have the time, please submit a review (again, post-flight) to EMRR

 

[Elapid]

and after i fly it, i'll be happy to write up a review.

i didn't quite expect it to be so big, thogh the product description does mention a 1000g weight

actually, it weighs a bit more than that.

first flights will be with single stage 29mm motor, i have a G64-4 RMS reload that i may send her up on.

that, or 3x D12-5?
that might be risky.

i have a few E and F 24mm reloads coming, so i'll have a lot more choices soon. i can't get the rocksim file to work, so i'll just have to wing it...

 

[BlueNinja]

Maybe you could put 3xG37's in the 3-24mm adapter.

 

[Elapid]

Originally posted by Blue_Ninja_150
Maybe you could put 3xG37's in the 3-24mm adapter.

i reckon i could if'n i had some...


I think the D engines will be ok. since single D motors have a max liftoff weight of 1lb, 3 of them should lift this 2lb bird safely. if only to a few hundred feet.

 

[jetra2]

It'll be a iffy shot, Elapid...I would recommend trying to stuff a fourth D12-3 in the center tube w/ adapters, cause 4 D12's in a two pound rocket is pushing it, big time!

Be careful!

Jason

 

[eugenefl]

Very sweet rocket indeed. I concur with Jason. Put a 4th D in the middle. Or heck, an E9 would be cool. If you've got the field, I say go for more motors.

Wow Jason...advising to add more power rather than to risk an underpowered flight resulting in a prang. (Inside joke - see the thread on the cluster 4" Der Red Max.)

 

[Elapid]

the rocket has a single 54mm mmt

i have two conversion mounts for each stage.

3x24mm

which looks like this when installed

or
1x29mm

 

[Elapid]

I'll shove the conversion mount a little farther into the tube when i actually fly this thing...

if max liftoff weight recommended by the manufacturer is 1lb, that leads me to believe there is a margin of safety built into that figure as any wise company would. since the max liftoff weight for 3 D motors is 3 lbs, a rocket weighing 2lb is well within the safety margin as stated by the engine manufacturer. by a full pound.

of course, the thrust doesn't meet the 10x rocket weight as recommended by many design guides.

of course, theory is just that.
anyone have rocksim that can see what the speed is at the top of the launch rod? i use a 5' rod.

i may just have to go buy a copy...
(elapid *grumbles* something about RMS and money pit, and 38mm...480Ns...600Ns...Kosdon 54mm....money pit...)

 

[AlexNUMB]

Wait wait wait...

You bought you were on the fence until I posted, then bought the kit last week, it was shipped from socal to grass valley (overnight?) you built it, and then post pictures of it?

So from order to completion of the kit is less than 10 days?

How do you do that?

--Alex

 

[Jerry Irvine]

Originally posted by AlexNUMB
Wait wait wait...

You bought you were on the fence until I posted, then bought the kit last week, it was shipped from socal to grass valley (overnight?) you built it, and then post pictures of it?

So from order to completion of the kit is less than 10 days?

How do you do that?

--Alex

Honesty
Commitment
Fortitude

Please learn. Thank you.

Jerry

 

[AlexNUMB]

Elapid-- Why are the pics all dated 2000?

 

[firemanup]

LOL someone forgot to remove the dates from the pictures.. of the rocket that was just finished this week but yet it's dated April of 2000..

ouch... them automatic date stamps can be a pain in the rear sometimes....

 

[Elapid]

Jerry got the kit shipped within a day or two ( i guess that's what he4 means by 'Instaship', i got it on Saturday


i could have finished it a bit quicker if i had used something other than 30-minute epoxy and jb weld (fin->MMT joints) for all the joints.


i used my dremel with 3 cutoff wheels screwed together to carve the fin slots and the dremel drum sander to bevel the fins.
those where the time-consuming portions of the build.

i decided i had better pick up a copy of rocksim so i could run some simulations with different motors/motor combinations. looks like the Estes D-powered flight would be iffy with any kind of a breeze at all. the rocket would only be moving a measley 24.3 mph...

i think i'll stick to 29mm RMS motors for now.

 

[Elapid]

and i don't really care...
lol!

Originally posted by AlexNUMB
Elapid-- Why are the pics all dated 2000?

 

[Neil]

What size chute ya need?

I got 28", 36" and 45" in stock....

Man o man thats a nice lookin rocket!

I gotta get me one of those puppies! The cost is up there a bit, but once the grass starts a' growin again... It shouldent take long.

54MM... Nice...

I cant wait to get mine!

 

[Elapid]

good move, alex!
i wish i hadn't been asleep at the wheel...

i do have some 38mm hardware on the way, 480/600(2)/720
that should give me some choices!
i think it's time to get a PIC-based timer/igniter/ejection system developed...

Neil
i think a 36" main and maybe a 15" drogue?
what do you think?
feel free to email me with pricing.

 

[Neil]

OK, I just sent you a PM.

A chute might be a little much for the drouge... I would use a streamer. you want it comin down at a pretty good clip for the drouge... Then slow it down for a landing with a slightly oversized chute. At least thats the way i would do it...

People who know more about this, correct me if I am wrong

 

[edwardw]

I wouldn't worry about finishing quicker when you used the 30 minute epoxy, just gave it time to soak in more and give it some more strength. I use West System 206 hardener - that can sometimes take 90 minutes to cure

Edward

 

[daveyfire]

Originally posted by Neil
you want it comin down at a pretty good clip for the drouge... Then slow it down for a landing with a slightly oversized chute. At least thats the way i would do it...

Aim for a 55-60 fps descent rate with a drogue, then blow the main for a nice easy touchdown appropriate to your field. Usually for a main I just stuff in the biggest chute that fits!

 

[Ryan S.]

for a rocket this size I wouldnt even use a drogue. The only rocket I have a drogue on right now is my Mission IMpossible and that is only a 24" chute

 

[lalligood]

There's a guy in my club who goes drogueless with his LOC Magnum. He uses 2 long pieces of 2" wide elastic or tubular nylon to act as a very visible & effective streamer-like device. I've seen it work beautifully for him 4 or 5 times, including once when the main never came out. Amazingly, it landed with NO damage! If that will work on a beast like the Magnum, it should work for a more slender bird like yours...

 

[Elapid]

lots of great info!
thanks mucho!

2" webbing as the drogueless drogue to a 48" Niel special chute...

first I need to mow some lawns!

 

[Neil]

LOL....

If the rocket weighs 2.3 pounds with burned out case, chutes ETC, you will get a 50 FPS descent rate with a 15" drouge. You will get just about 15 FPS with the 45" main chute (or Maine chute ).

You could definetly get away with a streamer or go drougless with a nice slender bird like that.

Lawn mowing... one of the best parst of spring, especially when you have a big yard 2 hours of pushing a smelly, noisy mower will get you quite a chunk of $$!

 

[Ryan S.]

I doubt the webbing is going to slow down the rocket that much, usually the shock cord just helps the parts fall unsabally which slows down your rocket enough. 2" webbing is going to take up alot of space

 

[Neil]

i still think caution tape or a long strip of ripstop nylon would do you fine... Or just the tumble. I dont think you need a chute at all for the drouge.

 

[daveyfire]

The only purpose of a drogue is to keep the sections apart before main deployment and keep the booster from coming in "ballistic". If your booster is stable without the nose section on, then a drogue is required (or some sort of drag device to keep the booster from streaming in too fast for your main to deploy properly... seen it happen...). Otherwise, go drogueless -- the rocket will actually fall slower because the unorganized parts just flop around in the air. With a drogue they will descend in a nice straight line.

 

[edwardw]

I'm also a fan of drogueless. I used the setup on my L1/L2 rocket. Everything came in fine. I separated the two sections with 15' of 3/8 tubular nylon. On the L2 flight (altitude was 6788) when the main deployed the data said they were dropping at about 100fps. Fortunately I have a parachute that opens very slowly so no damage at all was done to the body tube.

You would be amazed at how the body tubes also want to try and separate going drogueless, they really flop and flap around up there. I've seen a rocket with a drogue that the parts beat each other up because they were swinging like a pendulum. Also have seen a rocket with a drogue tangle a ton because they swirl around and you get a big mess.

Go drogueless!

Edward