Rubber Band Based Pistol Project (One Day Challenge)

thingiverse

https://www.youtube.com/watch?v=VhslHK4820I&feature=youtu.be Hello! As part of the one-day Project challenge, I created a rubber band pistol that can shoot anything from paper balls to pens! Please be careful with it; it's not meant to harm others. I just wanted to see if I could make it work. I'm a 16-year-old student from Israel playing for our local robotics FRC team as the head CAD department. Time spent designing and tinkering: 4 hours Time spent printing: 7 hours Clean-up and video making: 4 hours Have a great day! Print Settings: Printer Brand: Printrbot Printer: Simple Black Supports: Yes Infill: ~10-15 Notes: The infill and resolution depend on how many rubber bands you plan to use. Mine slightly broke with eight bands, but my print wasn't as invested. This print will take a lot of supports, unfortunately. Try printing the body of the pistol upside-down. I deleted the sights for printing convenience. Post-Printing: Supports: As I said, there will be a lot of them. Try removing them and sliding the canister across the body quickly for a few minutes. It worked wonders for me! How I Designed This: I used Inventor 2016 to create this, and I had a blast doing so! I roughly sketched the mechanics on a piece of paper and threw it into the program as a big, ugly blob. It took some time, but I managed to get it to resemble a Desert Eagle (let alone a pistol). There was a lot of math involved – everything from the power of the rubber bands to the friction of the trigger with the canister. To be honest, it wasn't simple at all, and Google helped me more than I'd like to admit. I had to redo and reprint parts many times for it to work and even more times to make it look like a pistol again. I had fun, and that's what matters! Custom Section: Project: Project Name: "Rubber Band Pistol" Overview & Background: We've always used old rubber bands to make a "gun" with our hands. Time to take it to the next level! Objectives: Scaling designs to human proportions, basic engineering, tension between objects, and balance between tensions. Audiences: This project is great for anyone from 9th to 12th grade. Even though I'm the head of the CAD department in our local school FRC team, I think anyone with basic knowledge can invent and make their own design with a little more time than just a day – although that would be a pretty nice goal. Subjects: Basic engineering. Skills Learned (Standards): Creative thinking; there are many ways to make this pistol! While there aren't really any new skills to learn from this project, it's a great way to finish off a class with one good end project. I've educated other students on how to design in Inventor 2016, and this project covers all the basic and a bit more – just enough for new students. Lesson/Activity: Now of course you can just give this task to a student and tell them "do that," but personally, I think giving them a free hand on this idea might be the best thing here. There are endless ways to complete it! Duration: For me, it took 3-4 hours to design this top-to-bottom. Now for a new student who just started, my guess would be about 2-3 days of easy and relaxing work – giving them more time to think. When I started, I had one idea in mind and developed it while working. New students might have a little problem with that sort of thing. Preparation: A 3D printer or a woodworking shop would be a good start, but not necessary. If you're working with Inventor or other programs, they need to know how to work with more than one object and think outside the box! This task could be really easy or challenging – that depends on the student. And of course, a handful of rubber bands! References: None. Rubric & Assessment: The general idea I liked is to just give them the name "Rubber Band Pistol" and tell them to be creative and go from there. The design I went with works pretty much like one of a crossbow, but each student can take it down a different path and make their own thing. Now grading this might not be as simple. I think the teacher should grade each work based on simplicity, efficiency, and other things like those. Another important thing is to not grade it based on how much power it can output – that will take away all the creativity from it, and everyone will make basically the same thing, but that's my opinion, and you're welcome to feel free to do whatever you like with that idea.