This year I have decided to build an Honest John Rocket. This will be my largest rocket yet. Many thanks to John for the design and knowledge of this build.

This rocket has a main body tube of 5.5 inches; the nose cone is 7.5 inches in the middle. The overall length of this rocket is 88 inches. At completion the rocket will weigh around 13lbs.

Construction:  Nose cone

Take one 18-inch peace of 5.5-inch airframe. Take one bulk plate and drill a half-inch hole in the center. And also place a u-bolt facing downward. Glue this bulk plate into one end of the 18-inch length of airframe. In the other end friction fit another bulk plate with a half-inch hole in the center. Now take a 4-foot peace of ½ inch dowel and slide through the holes in the bulk plates. Leave about ¾ of an inch out of the end with the friction fitted bulk plate. At the other end place a couple of drops of wood clue to secure. DO NOT OVER GLUE!!! Later step will explain why.

Next cut your Styrofoam into 9inch blocks. Find the center of your blocks with a straight edge. With a marker draw lines from corner to corner, the point where the cross is your center. At the point drill a half-inch hole. Your first block will need a whole the size of the airframe. Slide this block up and glue in place so that the top of the block is flush with the top of the glued in bulk plate. After that continue down the airframe, gluing all blocks in place until you are bout 4 inches from the bottom. Then slide the other blocks down the peace of dowel, also gluing in place. (Try not to get glues on the dowel)

Cutting the nose cone:

Next after all the glue has dried, it is time to not wire your cone into shape. This is why you need to leave about ¾ of an inch hanging from the bottom of the assembly made in the previous step. That amount hanging down will be your pivot point on the jig.

Now its time to hot wire the cone. Using a hot wire start at the top of your jig and slide the wire downward till flush with bottom. When it comes to turning the cone to start shaving more off, turn the cone as little as possible. By doing this it will give you a more rounded cone to work with.

This is what is should look like after almost two hours of cutting.

Now it is time for the sanding. My father and I came up with a good idea on how to do this. While he stood on the bench and operated the drill, I stayed on the ground with an extended sanding block. We used the drill to spin the cone in the jig. By using the edge of the jig I took the sand block and followed it just like I was using the hot wire. This worked really great to take the heavier amount of Styrofoam off.

After you finish sanding the cone so it is somewhat smooth, then it is time to glass the cone. What I used for glass was a 7-inch diameter sock. When you get the sock into position tie the sock off at the bottom and top so it tapers to the Styrofoam  nose cone.   This would slide over the cone perfectly. Make sure when applying your resin to the sock make sure that you are putting enough on. A good way I use to tell is if the sock has become transparent, and you can see the foam on the other side. Set the cone aside for a couple of day's to dry.

Construction of electronics bay:

First I took a 12-inch phenolic coupler that would fit the airframe that I'm using. Typically you would use a 3/8 thick ply bulk plate. On the other hand I stepped it up a notch. I used a 1-inch thick oak bulk plate. With that balk plate drill five ¼ inch holes. The first hole needs to be in the center of that plate. The other four need to be at equal lengths around the inner edge of the plate. These holes are to mount four threaded rods. I used a standard ¼ 20 rod. These rods will be used to hold the electronics board plate, align and secure the top bulk plate. This assembly is glued into one end of the coupler. On the other end is a 3/8-ply bulk plate that is drilled with the same holes as the bottom plate. The bottom plate and top plate on my rocket have ejection canisters mounted to them. In the 1-inch oak plate in the bottom I have inserted 4 threaded inserts to secure this whole unit into my main airframe. Through the holes in the center of the two bulk plates is were the ejection wires will come through. in both of these plates there is a u-bolt to tie shock cord and parachutes to.

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