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A New Opportunity to Over-Engineer a Cub Scout Balsa Kit!

Posted: Wed May 29, 2013 8:56 pm
by Scrollsawer
Just got back from our 2013-2014 Pack Activity planning meeting for the upcoming season. Looks like we're going to be conducting a Space Derby for the very first time, and I have zero experience with this event, so the twins and I will be learning all about a brand new Derby this year. Really excited about the chance to try something completely new.

I might have to run the event. If any of you have any 'tips or tricks' for this 'foreign Derby', I am all ears!

Sincerely,

Scrollsawer (or should I change my screen name to Buck Rogers? The Rocketeer? Rocket Man? Captain Kirk?)

Re: A New Opportunity to Over-Engineer a Cub Scout Balsa Kit

Posted: Sat Jun 01, 2013 3:29 pm
by whodathunkit
Scrollsawer wrote: If any of you have any 'tips or tricks' for this 'foreign Derby', I am all ears!

Sincerely,

http://www.derbytalk.com/viewtopic.php?f=17&t=6747" target="_blank

Scrollsawer (or should I change my screen name to Buck Rogers? The Rocketeer? Rocket Man?
Captain Kirk?)
NOPE: Just to..BUZZ.. Buzz..Scrollsawer...Maybe? :thumbup:

Re: A New Opportunity to Over-Engineer a Cub Scout Balsa Kit

Posted: Sat Jun 01, 2013 10:29 pm
by Scrollsawer
"To Infinity & Beyond"!

Re: A New Opportunity to Over-Engineer a Cub Scout Balsa Kit

Posted: Mon Jun 03, 2013 9:39 pm
by whodathunkit
Reduce air friction or "drag" by makeing all surfaces smooth as possible.
A blunt rounded nose causes less drag then a sharp nose.
A good design has all the leading edges rounded and trailing edges tapered to reduce the drag.

Rubber bands are the motor: so thay should be lubricated to help keep them flexible.
soak over night (spray silicon, ethylene glycol, castor oil, or two parts green soap and one part
glycerin and one part water,..)! Rub the mixture on the rubber bands about one hour befor race.

To help increase the rocket speed reduce the wall thickness to a minimum or 1/8 inch.
Do not weaken the area around the hanger (carrier) or carve away the nose button circle.

The little plastic straw MUST go over the hook:
(not just the shaft as the drawing shows in the space derby kit illustrates).
This is where the the rubber bands will hook on the wire hook..
With out the plastic straw liner, the hook will cut the rubber bands!!!

The plastic dowl at the rear of the space derby to hold the rubber bands must be kept from
rotating (groove out the back so the dowl can sit in it!) do not glue it!
You will need to remove it to reload rubber bands.
Groove for the rear dowl should be deep enough so the dowl does not twist when
rubber motor is wound tight.

Do not glue the front nose/propeller assembly into the front of the space derby it is pulled off to reload new rubber bands!
The propeller should have the rounded shaft -end pointed into (touching) the space derby
(this makes the bending of the wire easier & reduces friction).
Make the propeller shaft as short as possible by bending it close to the prop. Cut off the excess!

Stretch the rubber bands numerous times before loading, hand wind the bands numerous times before races (20 winds, then 40 winds, then 60, 80, 100) this helps relax the elastic properties of the rubber band.

Test the balance of the space derby rocket by hanging it with a string through the hole of the hanger fittings.. if it nose heavy carve or sand a little wood off the end of it!
if it's tail heavy remove wood from tail area.


Over- Engineered! Nope.. Good luck.. Scrollsawer.

Re: A New Opportunity to Over-Engineer a Cub Scout Balsa Kit

Posted: Tue Jun 04, 2013 9:04 pm
by Scrollsawer
Great information. Thanks Whoda! :idea:

Regards,

Scott (Scrollsawer)