Cluster reliability

[Veracity]

To all,

A friend pointed out to me that it seems as if clustering is something that rocket companies no longer promote. (Estes, for example)

I think the author of the handbook is not a big proponent of it either.

Is this the case, or am I wrong?

If it is the case, why? Reliability? Launch pad disasters?

V

[Chas Russell]

Clustering took a hit when the manufacturers went to putting the batteries in the controller. Four AA batteries do not weigh much, but they are also marginal for igniting just one motor. Back when Estes and Centuri offered launch systems that used car batteries, then clusters were cool because you could get a proper system. Once they went to the mass marketing "everyone" systems, clustering became a liability.
Centuri Sure-shot (actually RDC Ignit-rite) nichrome/fuse systems) were the best. Also the AG-1 flashbulb/ Sureshot fuse system was almost foolproof.
Then came REGULATION...

12 Volt car/marine/motorcycle battery with an appropriate launch controller used with a clip-whip or igniters used with wire extentions that are twisted together will usually result in a high percentage of clustering success.

Chas
NAR 9790

[JoeLaunchman]

I agree with that which makes it puzzling why Estes would market a rocket like the 36 D Squared which features a 2 D-engine cluster, then tell you that you need the E Controller. The E Controller uses the same 4 AA batteries as the regular controller, the only difference seems to be it has 30' of launch cable instead of 17'. This actually causes less current to reach the igniters.

I wonder if anyone here has had any luck igniting 2 engine clusters with 4 AA batteries.

Nowadays, I use nothing less than a 6V lantern battery with a controller I built myself with parts from Radio Shack. I think the Go Box is a good alternative for clustering, anyone here try it out?

http://www.apogeerockets.com/go-box_controller.asp

[Bohica]

I wonder if anyone here has had any luck igniting 2 engine clusters with 4 AA batteries.


You can light off 2 or 3 motor clusters fairly easily with the Estes controller but you have to have fresh batteries. I launched a Borocks Magnum (3x18) 3 times as a test and 3 times was the limit... Nothing on the 4th try.

Despite the above...I don't recommend it at all. I typically use a 12V jump box in conjunction with a Mercury Engineering Igniter Lighter. This combo has lit many different cluster combos (up to 6 Estes D's) and also lights the fire on Copperheads with no problem. A better system is of course one utilizing relays but the "jump box/Igniter Lighter" combo is a reasonable and reliable compromise.