Scratch Gaylord Original Design / Scratch Built

Scratch - Gaylord {Scratch}

Contributed by David Chance

Manufacturer: Scratch
(Contributed - by David Chance - 07/31/09) (Scratch) Gaylord

Brief:
A longish rocket with purple and yellow, consisting of 6 fins, 3 tubes, and a head lamp with a comic super hero embedded. This rocket was designed to be able to be flown on the D12-5 or the E9-6 engines.

Construction:
Surprise items:

  • 3 ping pong balls
  • Something from a gum ball machine–-a light with a comic superhero inside.
  • A plastic egg

(Scratch) Gaylord

Here are all the parts. As you can see, I received a gold mine of various tubes. Unfortunately, I only had one tube that would fit the nose cone with all the other tubes being of various sizes.

I didn't know where to start, so I started with the motor mount. I found a tube that would fit a typical E motor (24mm) and I glued in a thrust ring at the proper spot, approximately 2.75 inches from the end. The thrust ring was made by cutting a portion of the toilet paper roll an inch long, then cutting a portion of that out to give it a smaller diameter.

(Scratch) Gaylord

The next portion I decided to do was to create the upper fins. This was done by cutting a ¾ inch tube in 3 equal lengths which came to 2.75 inches each. Then I glued the 3 orange fins to them. In order for the fins to lay flat on the tubes, a slit was cut into the tubes so that the tabs of the fins would slide through.

(Scratch) Gaylord

Wow, looks great doesn't it? Now set those aside for a moment. Next I took the 1/8 inch thick balsa sheet and cut 3 fins. Each fin had approximately the following dimensions:

(Scratch) Gaylord

I then glued the balsa fins at the bottom and the 3 orange and tube fins near the top of the tube. I didn't have a good picture of this so I'll use a diagram.

(Scratch) Gaylord

There, the rocket is taking shape. Now I just need to add a bit of flair. I took one half of the plastic egg, cut a hole in it the size of the diameter of the lower body tube (1 inch), then slid it down the top of the lower body tube until it was just above the tube fin combos.

(Scratch) Gaylord

Now at this point, I discovered a problem. I liked that the half egg was there, but because it altered the overall diameter of the lower part of the rocket, I needed to place the launch lugs on some kind of standoff or else the launch rod would have to go through the egg.

I found another tube that was about 4 inches long and 0.75 inches in diameter. I sliced it in half lengthwise. Out of one of those halves, I cut a piece that was 2 inches long and then another piece 1 inch long, discarding the remainder. I then placed the 2 inch piece centered between 2 fins about inch above the bottom of the lower body tube. The other was centered in between the upper fins. Then, on each of the standoffs, I glued a portion of the launch lugs. (Scratch) Gaylord

Now to work on the payload section. This portion of the project was a little trickier. I started with the easiest part: the nose cone.

(Scratch) Gaylord

First, one of my surprise items was to be something from a gum ball machine. One day I was at my local Fuddruckers, chowing down on a burger with extra pickles and mayo when my eyes were pulled to the dank corners of the restaurant. Lo and behold were all these little machines with blinky lights that for years have sucked the quarters from the lint filled pockets of starry eyed kids. I was starry eyed. I sauntered over, wiping mayo on my sleeve, and side stepped a pickle on the floor... Then I delved into my pockets with greasy fingers and pulled out a couple of quarters. Moments later I had this light bulb thingy on a key chain. It had a switch on the side that when flipped, will give off a glow from the top. If you looked into the glow, you could see a super hero type of comic character, but with my poor eyesight, it reminded me of a muscular cat with a funny hat. I nicknamed him Gaylord. When I got home, I cut off the chain with my trusty old Dremel and cut the tip of the nose cone. I cut the tip large enough to fit the mini flash doohickey. I now had my nosecone.

(Scratch) Gaylord

Next comes the harder part: using the pesky ping pong balls. I decided that I was going to use the balls as part of a pod like object that would be connected to the payload section. I cut a tube that was ¾ inch diameter into a 5 inch long piece. In each of the ping pong balls--and this is where it was tricky because ping pong balls don't like to cooperate--I cut a hole that would allow me to insert the 5 inch piece. I then slid the first ping pong ball onto it until just a tip of the tube was poking out. On this end, I did a little something more. I found a tube that would make a perfect coupler for the lower body tube. I attached this to the end of the ping pong ball. The next step was to take 2 more ping pong balls and slide it down next to the others. Now I had something like this:

(Scratch) Gaylord

(Scratch) Gaylord

But I'm not done yet. I took the toilet paper tube that I had left over and cut a piece 3 inches long. This piece will fit over the ping pong balls snugly. Now I had something like this:

(Scratch) Gaylord

Now, I glued the payload section, which is a 1.25 inch diameter by 10 inches long tube to the payload side (the side with the 0.75 inch tube sticking out). Now I had something like this (please forgive my artistry):

(Scratch) Gaylord

On the end with the coupler, a bulkplate will be needed. I made a mistake while I was building Gaylord. I cut a piece of round cardboard from the box that I received the parts in and then glued it to the end of the coupler. If I was smart, I would have used this as an opportunity to glue in the shock chord inside the coupler. Then I could have glued in the cardboard bulkplate pinching in the shock chord inside the coupler for further "holding" power.

Using the folded paper method (glue the chord to a strip of paper and fold twice), I glued the chord to the inside of the lower body tube and far down as your little fingers can reach. The other end, I glued the chord to the base of the bulk plate in the coupler.

(Scratch) Gaylord

Finishing:
I taped over the flashlight thingy of the nose cone to keep it from being painted. I then sprayed primer, sanded, and sprayed another coat. After some sanding I used some purple paint that I found on sale, which was great because the flash light thingy was already purple.

(Scratch) Gaylord

Flight and Recovery:
On July 25, at MDRA's launch, I launched Gaylord on a D12-5. The winds were eastward at about 10mph. At liftoff, Gaylord made a nice slow liftoff and arced slightly into the wind to an altitude of about 500 feet. The ejection was less than perfect as my shock chord did not hold to the base of the bulkplate and there was a separation. Fortunately the damage was only minor in that the coupler broke on landing.

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