Derby Talk

So this summer, my son's pack is going to have a space derby. We have never done this before.

I know the physics behind pinewood derby racing, but very little about space derby.

What comes to mind is friction between the rocket and guide line, the friction of the propellor on its shaft, and weight. I'm assuming the propellors and rubber bands must remain standard issue, with no modifications.

Am I missing anything? Are there any tips to be offered?

No direct experience here, but what I've read in the past is that one thing you're missing is the friction in the rubber band as all those twists uncoil. Soaking in glycerin was the suggestion, as well as having several spares and seeing which worked the best. I've often thought that adjusting the flight surfaces to slightly counteract the rotational moment of the propeller and give it some lift to reduce the line guide friction would be useful. All just theory but given no other comments for several days I thought these might be useful.

Thanks for the input. I was talking with our CC at district today, and he mentioned a similar tip about putting dish soap on the rubber bands.

He also mentioned that more than one rubber band can be used- but he had not seen alot of difference between rockets that used 1, 2, or 3 bands.

I think I need to get my hands on a kit and play a little.

This is my first time posting, but I thought I would share what my son and I did with his rocket. We were building primarily for looks since we put so much into building his derby car for speed. I couldn't find many tips for building rockets, but I found some good info when searching for rubber band powered model airplanes. The info I found suggested that they used spools of rubber and just cut to length for what they needed. I noticed that the rubber bands extend well beyond the end of the rocket. We cut the rubber bands and used a square knot to make them about 2 inches shorter. We soaked them in a baggy with some armor all for about half an hour before the race. We used 2 rubber bands at 100 turns. At the race when the rockets were being wound it was apparent that my sons rocket was getting around 20 to 30 more usefull turns. I was kind of suprised to see how much faster my sons rocket was compared to all of the other rockets. Our rules were very loose so I don't know if this is allowed for your race. I hope you and your son fair well.

Thanks for the input, meancar.

The suggestions certainly make sense. I'll be curious to see what the rules look like when they pass them out.

lOOKING FOR INFORMATION ON SPACE DERBY..WE JUST FINISHED OUR FOURTH ANNUAL RACE AND HAVE LEARNED A LOT OVER THE YEARS. I HAVE A BROKEN HAND SO LET ME APOLOGIZE FOR THE ALL CAP TYPE.

MY WEB SITE http://pack252.greatplainsbsa.org... I am the webmaster and check my e-mail at least once a day.

We changed out our timers and went with the derby master software this year so we were consistent with our pinewood derby...

If i could help with any questions just send your questions to me or if you prefer to use this board just let me know and i will check it more regularly....

Bulldog wrote:Thanks for the input. I was talking with our CC at district today, and he mentioned a similar tip about putting dish soap on the rubber bands.

He also mentioned that more than one rubber band can be used- but he had not seen alot of difference between rockets that used 1, 2, or 3 bands.

I think I need to get my hands on a kit and play a little.

Soaking the rubber bands in glycerin works well too.