Clustering W/Copper Heads or 1st Fires ?

[Zippy]

I know that Aerotech's direction's for these ignitors say not for use in clusters but why not ? Is it a matter of amperage ? If I'm using say a big 750 amp car battery why would I need some other ignitors ? Or how about a motorcycle battery ? I'm looking to ignite two 29/40-120's.
If I have too I could buy some pyrogen and dip some Daveyfire 28 B's I allready have, but do I really need to ?
What say you cluster freaks ?

 

[rbeckey]

Heck, I have a hard time getting one Cooperhead to light at the same time, let alone two. I also use a 12 volt system with more than enough juice. I don't think I'd cluster them. I wouldn't use them at all it they didn't come with the motor.

 

[Zippy]

Rbeckey,

I wouldn't use the CrouperHeads (cough, cough) either if they didn't come with the motor. Thats why I want to use them though, the motors cost enough as is and I don't want to spend more just to lite 'em. I bought FirstFires as backups for the CrapperHeads and since I have two of those left I thought I might use them but they say the same thing about not being for clusters in the directions. Is the "no clustering" warning just so Aerotech can cover their own arse or is there some real reason for it ? I would think if you jolt 'em with enough juice everything would spark just fine but I want to be sure before I risk a new rocket and two motors.

 

[loopy]

I know it's a bad idea to use copperheads, but I'm not sure about the First Fire's. The only way to check is to run a test with them, I would say.

Loopy

 

[Zippy]

Loopy,

The PooperHeads are probably a bad idea all around. I am leaning towards a test of the FirstFires, although it will probably be a "live fire" test.

 

[jetra2]

If you want, You could buy a set of wires from Rocketflite and I'll be more than happy to dip them for you, if you'd like! I've gotten very good success with these igniters, which means instant ON ignition, no chuffing. Send me an e-mail if you're interested, ok?

Jason

 

[Adam Selene]

i would guess that aerotech suggests not using copperheads for clusters because even THEY know that the darn things just aren't reliable and having only part of your cluster light up is very very bad. i sometimes use them just because they come with the engines but i prefer to spend a little more for something that works.

 

[Zippy]

I think I'll be able to use dipped N28B's with Jason's help. I've got the N28B's and he's got the dip. Were both in the same start up (HERC) club. Wonderfull how TRF works ain't it?

 

[UhClem]

It is possible to ignite a cluster with Copperhead igniters. I remember reading a document on one of California Tripoli groups on how they did it.

1) Verify igniter is not shorted. This requires measuring the resistance at two locations to make sure that resistance is lowest closer to the pyrogen head. You will need an ohm meter with "Kelvin" test leads that can see differences in the range of milli-ohms.

2) A separate relay controller was used for each copperhead.


I built my own ohm meter (0.001 to 1.999 ohms) to check igniters and I have not had any trouble with copperheads that tested good.

I still wouldn't recommend using them for clusters though.

Good luck on getting the dipped N28B heads to fit the motor slot. An undipped N28B just barely fits the slot of a G64.

 

[rocwizard]

UhClem, that would be ROC's site. the article was written buy our own Hyam Sosnow.

You can check it out here:

https://www.rocstock.org/wizards/clusterwizard.pdf

HTH

 

[Zippy]

Hyam did a pretty good job on that article. Very informative.

 

[vjp]

Clustering with copperheads?

I would sooner play Russian roulette with an automatic pistol.

 

[bsexton]

Forget the Copperheads and try B&K Firefly igniters for D - H motors. Iv'e never had one fail and I believe they would work well for clusters. I know Performance Hobbies carries them.

 

[Zippy]

It will be a month or two till I actually need to lite them so I think I'm just going to get some pyrogen and go the N28B route. It's my cheapest long term option since I allready have the N28B's.

 

[eugenefl]

Originally posted by Zippy
It will be a month or two till I actually need to lite them so I think I'm just going to get some pyrogen and go the N28B route. It's my cheapest long term option since I allready have the N28B's.

Alright dude - spill the beans. Whatta ya clustering? Is it going to fly at HERC? Talk to Joe M. next time you're at HERC. He makes some pretty sweet dipped igniters. That's what he used on his 4-29SS this last time.

 

[Zippy]

I can' t spill the beans just yet Eugene. It's a secret project...
oh what the heck, I never could keep a secret. It's a 3" Jayhawk w/dual 29's. Gates Bros. inspired but not nearly so big. I'm using 9" long MMT's so it can take the 240 case easilly but at HERC I'm planning on F-40's or maybe less if it comes in light enough. I'll definatly have to ask Joe what he used, he did get them to both lite right at the same time. It won't be ready for awhile though, it's the most involved scratch build I've done so far.

 

[eugenefl]

Originally posted by Zippy
oh what the heck, I never could keep a secret. It's a 3" Jayhawk w/dual 29's. Gates Bros. inspired but not nearly so big. I'm using 9" long MMT's so it can take the 240 case easilly but at HERC I'm planning on F-40's or maybe less if it comes in light enough.

DROOL!!! I am so insanely envious! The Jayhawk just defines what a rocket should look like! Wow - dual 29s. We'll have to measure your Jayhawk's finished weight vs. my dual 29mm Deuce. Mine is about light enough to go on 2 E16s or E30s. First flight will more than likely be on F20-7s if I can find some. Make you a deal - I'll show you my rocket if you show me yours. (Ok, borderline childhood perversive or reminiscent. Let's keep it clean folks!) Joe's dual G40 flight was flawless. Ignition was istant. BTW, I wasn't able to get the 29 Deuce up at SEARS. 20mph winds can put a damper on rocketry.

 

[n3tjm]

Originally posted by vjp
Clustering with copperheads?

I would sooner play Russian roulette with an automatic pistol.

Someone got the Darwin Award for that one...


Info for the fire-arm illiterate:
Unless the automatic pistol has not been cocked, or it is empty, there is always a round in the chamber...

On the range, I usually have the breach open (slide locked back)on the pistols, so when I slap in a clip, I thumb the slide release when I am ready to shoot and the pistol is ready to fire...

 

[Zippy]

Eugene,

Well I don't have a lot to show right now. Just a 3" slotted tube, a couple of centering rings, a couple MMT's and the two G10 finlets. I'm still waiting on some plywood for the main fins, more G10 for the canards the nose cone and everything else. I think I'm gonna glass the whole thing, except the G10 of course becouse that would be silly.
Sorry to here you didn't get to fly the 29mm Deuce at SEARS. I was wondering about that.