Here are the materials you need to make this catapult. Ten popsicle sticks, a ruler, a pencil, scissors, a rubber band, and a roll of masking tape. The rubber band, when cut, should be at least 5 inches in length. Before you start making the catapult take a look at the popsicle sticks and make sure they aren't cracked or weak.
Some Masking tape Tips before you begin
There are some neattricks that I use when applying masking tape and you should use these techniques.
First off, cut yourself ten pieces of masking tape and stick them lightly to the table or the wall. This will make it easy to grab and use them.
Another great technique for using masking tape is to lay it on a table with the sticky side up. Then you can apply the craft sticks to it easily. And itmakes taping two sticks together very easy.
Now cut the popsicle sticks so you end up with what you see in the picture above:
• 3 pieces that are two inches long
• 6 pieces that are four inches long
• 1 piece that is three inches long (leave one rounded end on it)
• 1 piece that is four inches long (leave one rounded end on it)
Now take two of the four inch piecesand two of the two inch pieces and tape them end to end so it looks like one big long stick. The sequence should be short stick, long stick, short stick, long stick. (like this picture):
I tape them using the technique I described in the taping technique above. I lay a piece of tape on the table with the sticky side up then press the two ends of the sticks onto it. Wrap the tape aroundthem with three solid and tight wraps.
[pic]Now fold the assembly into a square and tape the final joint together. It should look like the picture here on the left. Use plenty of tape.
Now place a two inch piece on the inside of the structure like this.
And tape it firmly into place. Use at least three wraps of tape and do not put any tape in the center area of thesticks. I will show you why in the next picture.
[pic]You will be inserting a stick into that space in the middle so that's why you should leave the middle untaped. But don't insert it now. We will do that later.
Now tape two of the four inch stick together side by side like this. You are going to do this twice. Make sure to use plenty of tape and do at least three wraps around.
Make two ofthese and this is what you end up with. Two assemblies each with two four inch sticks.
Now tape these assemblies to your rectangular base. First you put tape on the long end like this picture shows.
Then tape it the other way like this.
This is what you end up with. The base is completed and you are almost done. Just a few more things and one thing I want to point outabout your taping so let's flip this base over and take a look underneath.
See how, underneath, the tape forms nice tight triangles? This will lend a lot of strength to the catapult base. So do at least three wraps and make it nice and tight.
Now tape the rubber band to the three inch popsicle stick as shown by laying it on the stick at the rounded end then wrapping it with tape. Do atleast four wraps and make it nice and tight.
Now insert that assembly right into the base of the catapult as shown. It slides tightly between the two pieces that are taped together. You will need to use a little tool to opend up a gap. Use a small screwdriver or the tine of a fork to get the gap to open up just a little then force the stick in there. It should be a nice tight fit and shouldstand upright nicely.
This is what it should look like.
Now we are going to make the hinge for the catapult. Stick a layer of tape right down on your table (sticky side down). Yup, stick it right to the table like shown at left. Then stick three more layers of tape right on top of it. You end up with a piece of tape that is four layers thick. Now peel this tape up off the table and...
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