From: rlosee@unlinfo.unl.edu (Robert Losee)
Newsgroups: rec.scouting
Subject: Re: Space Derby Help Wanted
Date: 16 Nov 1992 20:46:19 GMT
Organization: University of Nebraska--Lincoln	
Distribution: world
NNTP-Posting-Host: unlinfo.unl.edu

scottb@col.hp.com (Scott Brunton) writes:
[Well this is a first for me, responding to a post about real scouting,
not gays, girls, or godless on this group.  Thanks for the 
opportunity!]
  
>	Our pack has traditionally held a Pinewood Derby each spring and
>is looking to try a Space Derby.  I contacted our local DE to see if
>he knew of any other packs that may have experience in running one.  He
>was not aware of anyone.

We ran the Space Derby last spring, and then took it to the scout expo
where it was well received.  

>	I would appreciate help and direction in any of the following
>areas (and others if you think it important):

>	* how to construct the track
>		- I had been told that the runs can be as long
>		  as 50-75 feet ... apparently, these spacecrafts
>		  really fly!

The space in our church was probably about 40 feet, and I suspect
they could have gone much further. Mechanically the tricky part is
the starting mechanism.  We essentially made two saw horses out of
2x4s, we may have had weights pulling on the strings for tension (I
didn't build it but am just trying to remember it).  Hooks were made
out of coat hangers I think. These held the propellor.  It's also
necessary to have a wire against the actual rocket so the torque in
the rubber bands don't twist the rockets on the launch pad.  These 
were attached to the saw horses and stuck out about four inches.  As I
recall the hooks were on a dowel attached to the saw horse by velcro,
which was dropped to start the race.  My advice is experiment.  Our
designer dads got together for an evening creating different starting
mechanisms till they found one that worked.
 
>	* how to start them off
>		- I recall reading that a starting block can be made
>		  out of wood that would lock the propellors until all
>		  spacecrafts are ready to be released

>	* material to use a runners
>		- I had been told that monofilament fishing line works well

We used heavy duty mono, hard to see but people figured it out pretty 
quickly.

>	* how to determine winner (is electronic necessary?)
>		- again, I had been told that close finishes over a long
>		  run are not likely; however, placement may be important
>		  for subsequent rounds

We may have had one tie in forty kids.  They tended to spread out 
pretty quickly.  We just eyeballed it but gave up having a real race 
at the pack meeting (see below).

>	* your choice of advice
>		- I'm open to ideas!

We decided not to race the space derby rockets at the pack meeting
because a number of parents felt things were unfair. Here's the REAL 
IMPORTANT advice to try to avoid our problems:

*  set the track up with the length you'll need.  Then experiment with
the NUMBER and TURNS for the rubber bands (RB) needed for a rocket to
fly the length of track before the big event.  The directions are
ambigous and left a lot of room to interpret, which or course the
parents did.  We're still not sure what's right.  Some thought three
RBs were needed in the rocket, others one.  Our current hypothesis is
to use one RB (three seemed to bind and then break pretty easily). 
Then run the rocket with 50 turns, then 100, then maybe more till it
loosens up. I use the word hypothesis deliberatedly as next time we
run we're going to experiment before the big event.

*  have the lubricating solution and extra rubber bands on hand.  I'm
guessing at least half the rockets had to be recalled to change out
the RBs. Had we tried running our tournament as planned (double
elimination I believe) we'd have been there all night waiting for
contestants to reinstall the RBs, or having the winners be the lucky
ones with good RBs.  Have a table set up with solution and fix up
parts (which you should also have).  Also USE THE SAME KIND OF RBs. 
The spares we got at the office supply store weren't the same as the
rockets came with, again leading to cries of foul.

*  have the scouts team up with their parents to count the number of 
turns for each rocket.  Have 'em winding up when they're in line to 
go.  We tried the wiring thingy that you're supposed to put in a hand 
wood drill, but it didn't work so well.  We resorted to hand turning 
all props.

*  tell the parents they'll have to change rubber bands, so don't glue
the nose propellor unit or the bar in the back onto the rocket.  Help
them figure out which way to turn the prop so that it spins
correctly.

I'd encourage you Scott to use an ad hoc race format we were forced 
into.  In the end we just had a line of kids coming up running their 
rockets against their buddy's or other dens.  It was spontaneous and 
fun for them, without the pressure of winning the derby.  If their RB 
broke they went back to fix it and got in line again.  I think an 
organized race such as double elimination would be difficult.  Too 
many technical difficults and variations that can result in time 
delays and parental squabbles.  Most kids left with smiles without 
doing it this way.  Winning SD is based less on good design, and 
more on the luck of the RBs, the bounce in the lines, etc..  

The most memorable rocket in our group looked like a milk bottle with 
the name "Milky Way" on it.  Loved it.  Maybe you want a design 
catagory but we just gave ribbons to everyone.

Hope this helps.  If you really need to know more details about how
the starting mechanism works I'll take a look at it.

>	Thanks, Scott Brunton (scottb@col.hp.com)
Bob Losee, Cub Master, Pack 29
--
*-------------------------------------------------------------------------*
Robert D. Losee                 BITNET: ucas402@unlvm
University of Nebraska          Internet: rlosee@unlinfo.unl.edu
Lincoln NE  68588-0496          Phone: (402) 472-7663