Rocket Rubber Band Length

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tpica
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Location: Derry, NH

Rocket Rubber Band Length

Post by tpica » Thu Jan 17, 2008 9:20 am

Got a question about the space derby kit I just got. The rubber bands are much longer than kits I had in the past. A reasonable length for a 7" rocket with a prop assembly 1 1/4" max should be between 5 3/4" to 6 1/4". The rubber bands in this kit come in at 7 1/4" and hang out the back of the rocket. It takes 6+ turns just to hold the dowel in place. Has anybody else seen this? Any suggestions to shorten up the rubber bands?

Thanks

Tony Pica pack 405



BlackLotus
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Re: Rocket Rubber Band Length

Post by BlackLotus » Thu Jan 17, 2008 10:42 am

Someone in an earlier post suggested cutting about 2 inches off each band and using a square knot to tie them.

viewtopic.php?t=2737

I don't know if anything in your rules would prohibit this but, it is an idea.

Anyway, just for comparison, the rubber bands in our kit are about 7" without any tension.



tpica
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Re: Rocket Rubber Band Length

Post by tpica » Thu Jan 17, 2008 11:59 am

We were considering tieing a knot on 1 end of each band creating about 1/4" loop of excess "engine" and slipping the dowel in behind the knots. We were concerned the excess loop in the back would create drag. If we were to cut them off, then the square knot idea would be better so it doesn't slip. Either way, you're right, we don't know what the rules say about it other than we need to use the parts from the kit. Still, I went to find my Life Scouts old rocket from his Webelos days and confirmed the bands were almost 1/2" shorter in past kits.
Anybody know what the rules say about "shortening" (we are calling it supercharging) the engines?

Tony



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