Space Derby Assembly

We promised and now we've delivered!  Hopefully these photos of Nathen putting together his rocket will help you all put yours together.  Remember that our space derby is Tuesday, January 22, even though there is no school!  If you're still unsure of how to put the "motor" together, bring the rocket to scouts on Tuesday the 15th and see Ryan or Amy for assistance.  Don't forget that you can email Ryan any time at evannpd@charter.net if you have questions. 

First, start off with your 2 blocks of wood and some wood glue.  Have your scout put a line of glue down both sides, but not so much that it oozes out the side.  Making sure the same size holes line up, place the 2 pieces together.  Your rocket should now look like the photo to the right.  The small hole will be the front of the rocket, the larger will be the back.

Now it's time to shape the rocket.  The easiest (and safest!) way we've found is to use a vegetable peeler.  This is balsa wood which makes it very soft.  Please do not allow the boys to use pocket knives or electric sanders for this.  Those will only destroy the wood. Truly, the peeler works amazing!  After the basic shape is there, sand it smooth! 

Mom or Dad can step in at this point.  A notch needs to be made in the top of the rocket for the hanger to fit in.  Any kind of sharper object can be used: pocket knife, butter knife, even the side of the hanger piece itself will work.  Be sure not to make the notch too big or the hanger will not fit well.  This piece is super important as it's the piece that will hold the rocket to the "race track" on race day.  Glue this piece in place with the rounded part facing the front (toward the small hole) Make sure it's glued in well!  If if comes out on race day, chances are the rocket won't be able to be raced.  We did this part before painting in hopes that the paint will act as an extra way to help hold it in place. 

  

Your scout can get creative with this next step.  There are 3 plastic pieces in the kit that are designated for fins.  He can draw whatever shape he'd like on these pieces.  (obviously use pencil in case it needs to be erased)  He can cut them out and affix them after he's painted the rocket.  He can feel free to use sharpies to decorate the fins or he can even paint them.  That's totally up to him.  We won't show this step since Nathen wants to keep his finished product a secret, but they are easy to attach.  Just cut a small slit in the rocket and using wood glue, glue the fins on.  They can go just about anywhere on the rocket. 

Here's where Mom or Dad will come in once again.  This step is mega important and for some crazy reason, they don't really go over it in the instructions that come with the kit.  The way the space derby motor works is this:  there are the 3 elastics inside that will get wound up.  Once we let the propeller go, the rocket flies down a line of fishing line.  In order for the elastics to do their job, one end must be held in place.  This step will allow that to happen.  On the back of the rocket (large hole end, remember!) you will have to cut a notch to hold the little white dowel in place once the propeller is released.  First, hold the dowel where the notch should go, roughly in the middle of the back.  Mark where you are going to cut out.  Using a pocket knife cut out little grooves that are the same size as the dowel.  Hollow them out just enough so that the dowel will stay in place.  Too much bigger and the dowel can

pop out causing the rocket to malfunction on the line.  The elastic will be wound around this part once you finish assembling the entire thing.  DO NOT glue or otherwise permanately affix this part to the rocket.  We may have to do some maintenace to the rocket on race day and if this gets glued down, there's not a whole lot we can do to fix the rocket.  The final picture shows how the dowel should fit in the holes.   

Now it's time to assemble your motor and propeller pieces.  The following photo shows all the pieces you'll need to do this step.  

First thing to do is to take the metal piece with the "o" at the end and the little red tube.  The tube should slide quite nicely over the metal piece.  Before sliding the tube on, however, you will need to cut about 1/4 inch off the end of it as this has to be threaded through the propeller.  The picture below shows the tube on the wire PRIOR to being cut.  It's much easier to cut yours first!  Make sure the entire hook part is covered.  This is what will protect your elastics from being damaged. 

Next step: assembly! Lay your pieces out as shown below.  Do note 2 things: the little tiny brass bushing that is right above the white knob and the propeller...the middle of the propeller has 2 sides to it-a smoother, rounder side, and a flat side.  Make sure the flat side is the side facing away from everything else.  The little bushing should fit snugly inside the little white knob.

Thread the metal piece through everything.  If it doesn't fit all the way thru because of the red tube, feel free to cut more off, but only tiny pieces at a time.  (you can see how our red tube is shorter in this photo since it's been cut)  The picture below shows the unit just before the propeller is added on. 

This is the flat part that should be facing out when the propeller is aded.  Remember--round side in!

Now the propeller is added on.  Give it a spin!  It should go around relatively freely.  The next step seems pretty simple, but is actually very important.  The wire needs to be bent down over the propeller ( a pair of pliers works the best for this.  Just be careful not to bend any more than just the end).  This wire is what will allow us to wind the elastics on race day.  If it's not secure enough, we will be winding the rocket but the elastics will keep coming undone.  To know it's done right, after you've bent the wire down, you shouldn't be able to spin the propeller while holding the hook.

Now all that's left is to attach the elastics!  Remember that we're using 3 elastics and 3 elastics only.  Using only 2 won't propel it enough and more than 3 will just jam up.  If you want to soak your elastics in a lubricant (castor oil is recommended) feel free to do so a day before the race. 

They simply slide into the hook part of the metal piece with the red tube.  Make sure to only do 1 at a time so as to not overstretch the elastic.  To put the entire thing together (and again, Nate wanted to keep his a secret so we're not showing any more photos) you'll need a special "device" to help thread the elastics through the rocket.  What we use is a metal coat hanger flattened so it fits through the rocket.  The hook can catch the elastics and pull them through the rocket.  The white knob should fit snugly in the small hole at the front of the rocket.  DO NOT glue in place!!  Wind the elastics around the dowel, put the dowel in the notches at the back, and you're ready to go! 

Your scout should be able to do most of these steps on his own.  Let him get creative with the painting and the fins.  If he wants to put a number on it, he may.  Just be aware, however, that he may end up getting a different "official" number on race day.  Feel free to google "cub scout space derby" to get other ideas and tips.  Our plan is to have this be a den race and not an individual race, so there will be no single winners.  Our top den will be the proud recipient of our spirit stick! 

It may be tempting for boys to keep winding the propeller to see how fast it goes.  Please discourage boys from doing this!!  The more they play with it, the weaker the elastics become and less effective they will be during races.  Remember to bring your extra elastic to the derby--just in case!

Please remember that if you have any questions, either email or call Ryan or bring your rocket and parts to your den meeting on Tuesday the 15th for assistance.  Happy building everyone!