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Wade Sun's 13 Rules of Invention Success - Part 3

1Wade Sun is the inventor of the Disc Eraser™. He has written an article for AmericanInventorSpot.com AmericanInventorSpot.com readers as a guest blogger. Yesterday, we published Part 1 and 2 of a 4 part series on his 13 Rules of Invention Success. Here is Part 3 of 4: * * * * * * The next step: designing my product/final prototype. When you design a product, you need to weigh the factors of material cost vs. functionality vs. size vs. safety vs. appearance, among many other things. To beat out the shredders and the hand-held CD scraping devices, I wanted my device to be compact, portable, and small enough to fit inside my pocket. Smaller is better, for inventoring and shipping purposes, and being compact and lightweight is a definite plus. Looking at my first prototype, I determined that I could make my final prototype even smaller without compromising the stability. For added safety, instead of a retractable blade design, I thought about making a hinged baseplate that opened in simliar fashion as the paper trimmer, with the CD alignment stubs on the inside surface. In terms of engineering and manufacturing, a retractable blade would complicate my product's development as well as increase production costs. RULE #8 KEEP YOUR DESIGNS SIMPLE. I reasoned that the blade did not protrude out much from the slider because the distance from the CD surface would be very close. Besides, with my hinged plate design, the blade would not be exposed during operation. So there would be no need for a retractable blade mechanism. 1516 With these implementations in mind, I looked for a small, thin box. I could have made one out of clay or cut one out of styrofoam, but I was lucky to find a plastic pen box that was the size I wanted. 1718 Inside this box was a plastic black tray, and I taped both open ends and cast the mold around this tray to be used as the new body shape of my final prototype. 1920 RULE #9 BE EFFICIENT. Instead of making two molds for the two different hinging pieces, I would use the same mold to make both the top piece (with the slider railing assembly) as well as the bottom alignment baseplate. Unlike my first mold, which was a hollowed cavity mold, I came up with an entirely different approach: to just leave it open, doing half and half. Gravity will keep the surfaces nice and flat, and should prevent the warping and bulging that I encountered with the first mold. My first mold was simple, to duplicate the baseplate that I had made out of the pieces and clay. This time, it wasn't duplication; I will actually use the mold to create something new. That means, I will have to reverse-cast the "innards" first. I reverse-cast the middle railing from the original slider assembly and peel it out after it cured overnight. I coated the base mold beforehand with vaseline to prevent the slider railing from fusing to it. Since I had to make a slot where the CD would go through, I cut out a small strip off the edge of my first silicon mold. I also cast a thin CD mold to get the shape and middle hole of the CD, which I carefully trimmed out with scissors after superpositioning it relative to the slider slot and the body cavity size. 212223 Mold with the innards, ready to cast. Finally, I am ready to cast my two-piece prototype. With the slider railing carefully positioned inside the cavity, I mix and cast the top piece and allow it to cure overnight. 2425 After removing the top piece from the mold, I remove the strip and the railing from the cavity and cast the bottom base piece inside the same mold. This takes two sessions, because I need to make a beveled surface. I first cast the foundation. After that cures, I position the thin CD shaped mold over the foundation, then fill in the middle hole and the sides with casting to form the CD alignment surfaces. 2627 Taking the top piece, I snap my slider inside and check for smooth and straight operation. It was straighter and much closer to perfection than my initial prototype. My idea of reverse-casting with a half and half open mold worked! I sanded off the rough edges. Hastily, I used some scotch tape to hinge the top and bottom pieces together and inserted a CD to try it out, and it worked smoothly and beautifully! 2829 I needed a stronger hinge, the scotch tape was only temporary. So I shopped around, looking for the smallest, flattest metal hinges in local hardware stores. It seemed like they weren't small enough, and that it would be too difficult to implement (I'd have to drill small holes in both of my pieces, risking damage if I failed). Then, I saw some adhesive bathtub sealing strips and decided that would be a quicker and easier way to hinge my pieces together. RULE #10 BE OPEN-MINDED AND CREATIVE. Just because you need a 'hinge' doesn't mean you should look for a 'hinge'. Anything easier that would serve the same function will suffice, so keep your eyes and options open! After all, you are inventing here; it's better to come up with new, unconventional ways. Don't do things the 'normal' way. Try other things. You may discover something totally new and unique in the process. Many great technological breakthroughs have been discovered "by accident". This is why being open-minded and creative is my RULE#10, you will greatly increase your chances of invention success. 30Bathtub caulk strip? Yes! Copyright 2006. SunZag Creative Products. All rights reserved. Reprinted with permission from the author. ****** Part 4 of Wade Sun's 4 part article on his 13 Rules of Invention Success will be posted here tomorrow. news weblog technology computers Wade Sun Disc Eraser inventions prototyping hobbies misc. science