User:Dross4565/enes100/My Work 3

[|Link To Rubberband Project]

Write problem/project Goal
Design and make rubber band gun

My First Task
Make a decision matrix and let class or team pick out model/structure of rubber band gun team will start building. Take the sheet of wood we found in class and start cutting out pieces for gun.

Design of Rubberband gun group picked:

10 Round Gun Video

Summary of actual work over second weekend
Decided on which Model we were going to use for the project, and started cutting out pieces for gun.

Week1 Narrative
Each member all using the same design that we all picked out, the 10 round rubber band gun, using the tutorial.

Materials:
 * A 48x4.5 inch piece of wood
 * A basic ruler with centimeter and inches
 * Pencil
 * A wood saw(or anything else that will help you cut wood)
 * A calculator (to help convert millimeters to centimeters if you don't know how)

Found a piece of wood in the back of the class room, but thickness wasn't big enough for the specifications of the rubber band gun. So decided to use the piece of wood anyways, just using wood glue to glue to pieces together of the same cut to make exact thickness needed. Using the tutorial I started to make measurements. First, I measured off all the specifications for the barrel, trigger bar, sliding bar, etc. just using the outline. Once the outline of the pieces were cut out, I measured the "special" cuts each piece had. For example, the sliding bar and barrel have knicks in them to make the sliding bar move. Once this was done, I glued together the same pieces making it the right thickness and then trimmed the pieces up to rid off overlaying wood.

My Second Task
Start gluing pieces of gun together and attaching to one another to make gun. Then test gun out.

Summary of actual work over second weekend
Forgot to cut out pieces to the gun, making building difficult. So had to rebuild gun.

Week2 Narrative
Last week I cut out all the pieces for the gun with a hack saw, but forgot to cut out the wood and plastic plates to hold the gun together. So putting the gun together was complicated until I figured out I had pieces missing. Also using the hack saw to cut the pieces out of the plywood made the pieces rigid along the edges. So had to rebuild the gun, but this time used a jigsaw to cut the wood and plastic pieces making it more smooth and precise. In building the new gun I used the following steps:
 * 1) Drill a hole 2mm in diameter in pieces P1 and P2.
 * 2) Glue P1 to P8, and P5 to P6 to Trigger-Bar. Then glue the P1/P8 piece to one side of the trigger bar
 * 3) Glue P2 to the side opposite of P1 on the Trigger-Bar.
 * 4) Insert Ratchet into Ratchet-box, and insert two wood pins (2-3mm diameter) to the each holes.
 * 5) Fix Barrel to Frame L with screws.
 * 6) Glue P7 and P9 to Frame L.
 * 7) Put Trigger-Set on Frame L, and contact it with P7. Glue P10 and P11 to Frame L. Glue P3 to Frame L. Glue P4 to Frame L.
 * 8) Glue Grip L to P3 and P4. Glue P12 to Grip L.
 * 9) Put Trigger-Set and Sliding Bolt on Frame L. Contact Trigger-Set with P7.
 * 10) Drill a hole (2-3mm diameter) to Sliding Bolt, and insert a wood pin to the hole.
 * 11) Glue Releasing Plate L to Sliding Bolt with a glue for plastics.
 * 12) Glue Release-Plate R to Sliding Bolt.
 * 13) Fix Frame R with screws.
 * 14) Glue Trigger Guard to gun. Glue Grip R to P3, P4 and P12. Set a rubber band for Trigger-Spring and Ratchet-Spring.

My Third task
Start testing the rubber band gun and make sure it works properly. If not, make proper adjustments. Also compare my rubber band gun to the rest of the team, pick the best one out of the group and start making advancements on that gun.

Summary of actual work over third weekend
Last week I didn't have the opportunity to post the video on my father and I cutting out the wood pieces using a jigsaw because for some reason the video wouldn't upload completely from a mac to youtube in time. I took a day for the video to actually show up on youtube, so here is that video: Rubberband Gun Cut Out. Last week was all about building the gun, which I finished. This week I want to enhance the gun.

Week3 Narrative
This week, after finishing the gun, I tested the fire capability of the rubber band gun by using different size rubber bands to see how far each rubber band shot. What I found was that rubber bands being 1/8" thick and 2" in length seemed to shot the farthest. Any rubber bands in less thickness than that, seemed to not have the resistance to spring back into original shape. Making it so when you fired the rubber band from the gun it just seemed to fall off. The rubber bands thicker than 1/8", like 1/4", were too resilient and were hard to stretch enough from the back of the gun to the tip. After finding out which rubber bands suited best with the gun, I wanted to upgrade the gun to make it less difficult to reload. For example, the gun is built so that after the rubber bands are shot, the barrel of the gun slides forward pushing the rubber bands off. To reload the gun, there is a built in rachet box in which u have to pull down in order to push the barrel back to its initial setting then reload the gun with rubber bands. I want to make a recall system on the barrel so when it finishes firing it will spring back into place on its own.

My Fourth task
For my fourth task, I'm building a decision matrix on how to go about building this recoil system for the barrel of the gun instead of having to push it back after pulling down the rachet system built in to it. After deciding which recoil system will work best for the gun, begin building and testing in trail and error fashion.

Summary of actual work over fourth weekend
Over the weekend, the rebuilt gun I had built broke at the trigger part because the piece was divided into three parts. upon pulling the trigger, it had split where I had glued and instead of re-glueing the whole thing, I decided to recut the trigger and make it into one big part making it stronger.

Week4 Narrative
This week, I presented my idea for a recoil system to the class in which this experiment has taken place and expressed my ideas on the matter, but none was concerned about the recoil system as much as the completion of the gun itself. So looking more on the tutorial site I found numeral recoil systems the company had used Recoil Systems for Rubberband Gun. I decided that type A was the best one that resembled the rachet system within our gun design and researched the different guns the company had built with the same rachet system as ours. What I found was that only the machine guns had a recoil system with this type of rachet system by using a motor the website called a Tamiya's gear box and the rotary cam. Because they made machine gun's the motor was more ideal and it pulled the sliding bolt within the gun back itself by attaching string from the motor to the sliding bolt. Within our gun, we have no use for a motor so I thought about attaching a rubber band from the tip of the sliding bolt to the back of the barrel. That way when we would release the rachet system, the sliding bolt would snap into place instead of us having to guide it back with our hands. Im currently building and testing this method by trial and error, using wood nails for the holding spots on the barrel and sliding bolt and seeing how much strain I need to put on the rubber band for it to force the sliding bolt backwards.

Video of completed rubberband gun firing Finished Rubberband Gun

For the next group, I would suggest purchasing the Tamiya's gear from the website and seeing if u can't make our 10 round gun automatic gun compared to a semi-automatic, all u would have to do is rebuild the trigger system and add more cuts to the barrel if u wanted more ten 10 rounds firing.

Complete Team Page
[|Link To Rubberband Project]