6 D12 engines?

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Mar 9, 2004
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I need to be able to ignite 6 D12 engines simultaneously using just the estes electron beam launcher. I have modified the launcher so that it uses heavier guage wire, and am using a 7.2 volt RC car battery to power it.

Would this configuration be able to light all 6 engines at the same time? or would another batter, 14.4 volts, be safer? Thanks
make an aliminum foil bowl fill it with black powder. take one igniter and put it in the middle. That would ignite all the motors without a special controller ;)

wow flashpan is awesome
And now for the mandatory public service announcement always associated with this sort of advice:

</begin soap box statement>

Do not try this at home!

If you want to start trying flashpan ignitions, get someone with some experience at it to help, for heaven's sake! This isn't just something to be thrown together on a whim, and is potentially VERY dangerous.

</end soap box statement>

umm...ok...i dont think im gonna do that cause these rockets are on a BOAT .. on water....so ill need to light it in a normal way.

is 14.4 volts enough, or is 7.2 just fine?
You may be better off going with a car battery and a 6-headed clip-whip.

The key will be how many amps your pseudo-relay modified electron beam controller will deliver.

I'm no expert, so I don't have much to add here - other than:

"Good luck."

I would feel much more confident with a 12v or higher system for a 6 igniter launch. Makes no difference if it's 1/4a3-2t's or E9-6's - they all use the same igniter.
And now for the mandatory public service announcement always associated with this sort of advice part 2:

From the Model Rocket Safety Code:

Ignition System. I will launch my rockets with an electrical launch system and electrical motor igniters.

I don't think igniting black powder with an electrical motor igniter that in turns ignites the engine is exectly what they had in mind when they wrote the above....

The analogy would be to pour a trail of black powder leading to the flashpan containing more blackpowder and igniting the black powder trail..... I don't think anybody would consider that safe or smart or legal.....

From the High Power Rocket Safety Code:

I will use only electrical igniters recommended by the motor manufacturer that will ignite rocket motors within one second of actuation of the launching switch.

I don't think any self respecting motor manufacturer would advise anybody to use flashpans/black powder as an igntion methodology for their products....

I might add that the Model Rocket Safety Code is part of NFPA 1122 while the High Power Rocket Safety Code is part of NFPA 1127 and that NFPA 1122/1127 are the state laws in at least 30+ states.....
Originally posted by dohboy
umm...ok...i dont think im gonna do that cause these rockets are on a BOAT .. on water....so ill need to light it in a normal way.

is 14.4 volts enough, or is 7.2 just fine?

I would go with 14.4v. I have lit up to 4 motors with a 7.2v nicad r/c battery pack, (nicad's rock) but 6 would really be pushing it. (4 was pushing it).

BTW - 6- d12 motors would fall into the LMR catagory and require an "FAA notification" launch.
Ok, I know Carl is going to ban me from TRF from saying this :D , but the example set forth by the ATF should be a clear indication that it's unsafe to launch from a vehicle. Perhaps you might reconsider. ;) (Just teasing of course. I suppose it's always worth a chuckle to picture of bunch of "pros" having their master plan backfire. No pun intended!) Sorry Carl! Those good 'ol ATF boys can come visit me. I'll buy 'em a beer! Pfft!
Reliable Cluster Ignition will only by obtained with a RELAY system and a Large amp/hr battery at the launcher not at the controller. Clustering BP motor is my other great love. Please read the section on clustering in Stines Handbook of rocketry and/or Tech-Tip 006 BP motor clustering in the library section of Narhams.org. which will give you 30 some years of clustering tips and relay building instructions.

OBTW unless your flying with a waiver, 5 D12's is the limit within the 125g(4.4oz.) of propellant/1500g(3.3lb) LOWT safety code, or 4 D12s if your flying without a notum, under the 113g(4oz.) propellant/453g(1lb)LOWt safety code limits.
And now for the mandatory public service announcement always associated with this sort of advice part 3:

I personally would not launch from a boat. You didn't metion what type of boat, but be aware of gasoline fumes and the like.
Just because you are surrounded by water doesn't mean that you are safe from fire or explosion.

Gas fumes have a nasty habit of hanging around in odd locations on boats. Hence the engine compartment blowers.

Also, think about safe distance. 6 D-12's are a complex F-G motor. Is your boat at lease 50ft long? Your 15-foot electron beam line puts you too close. You should always double (at least) the minimum safe distance when igniting clusters.

Please don't put yourself or anyone else in that kind of danger.
I'd also recommend at least 30 feet distance for the launcher for safety, Never from a vessel you are occuping!
If the boat or vessel is moored off shore with a remote WIRED controller (Not RC) I'd say the boat launcher idea is...well... Whatever floats your boat:D
Wait, wait wait!!!

I need clarification please!

You said the motors are "in a boat"??? As in a rocket powered boat! Right?

Not launched FROM a boat!

That would be different!

A rocket powered boat would be no worse than a rocket powered car...but 6 motors???

I would be concerened with stability, water has a whole lot of drag!

The more this thread seems to go on the less feasible the whole thing becomes.

I can understand wanting to do something challenging, but this idea of a water based launch , together with custom ignition , and with a somewhat dubious motor configuration seems too complex. There are too many untested or untried methods bundled together in one plan.

Break it down a little huh ?

Try clustering and ignition in steps , if you can, sort out a towed floating platform and get all the permits and so on , try a single stager unclustered rocket from that.

Tell you something tho , if you can get it all together I want to see the video !!