The following design provides a cheap, simple, and unique way to create a rocket rail that will provide for a smooth launch every time. Materials include a 4-20 pipe, round headed bolts, part of a office chair, string, and a few stakes.
Step 1: Drilling the Holes for the Office Chair
In order to insert the 4-20 pipe into the base of the office chair, you will need to enlarge the size of the hole. This can be done by drilling into the top hole of the office chair base using a step drill. Once this is done, a smaller hole needs to be drilled at the bottom of the chair platform so a bolt can pass through. This can be done by using a regular drill bit.***Note***: The top hole will be much larger than the bottom hole. The rail will be going through the top hole while a bolt will be going through the bottom hole. In order to make sure that bottom hole is lined up with the top hole, look for a marking on the bottom outside part of the chair platform. This will indicate the center, and this is where you should drill the hole.
Step 2: Creating Thread for the 4-20 Pipe
This step requires the use of a threading tool in order to create thread for the 4-20 pipe. Simply take the tool and slowly twist the tool clockwise into the hole at the center of the 4-20 pipe. Keep twisting until the thread is at a satisfactory depth.
Step 3: Inserting the Pipe Into the Chair Platform
In order to complete this step, simply insert the 4-20 pipe into the top hole with the threaded side of the pipe facing into a hole. In order to fully secure the chair platform to the 4-20 pipe, use a bolt and put it through the bottom hole. Then take a wrench and screw the bolt so that it catches the threads of the 4-20 pipe.
Step 4: Adjusting the Rail's Position
At this point in the build you may notice that the pipe exhibits an unstable attitude, and is able to move back and forth slightly. To fix this, begin by installing bolts at the very top of the rail. To ensure that the bolts do not move, install a nut at the opposite side. ***Note***: Do not install the bolt on all four sides as one side will be use to hold your rocket. Once this is done, take string and tie it onto each bolt. On the opposite end of each piece of string, attach a stake. Ultimately, each stake will be driven into the ground in order to create the tension that is needed to mitigate the wobbly attitude that was originally exhibited by the rail. With this last step, your rocket rail is now complete. Enjoy!