David Lang, something of a reluctant maker, is on a journey, intensively immersing himself in maker culture and learning as many DIY skills as he can, partially through a generous arrangement with our pals at TechShop. He’s regularly chronicling his efforts in this column — what he’s learning, who he’s meeting, and what hurdles he’s clearing (um… or not). –Gareth
In honor of Plastics month here on MAKE, I’m excited to chime in with some of my recent Zero to Maker exploits in the world of silicone. For the non-maker (or “pre-maker,” as I like to say), working with plastic can be revelatory. It opens your eyes to the wonders and possibilities of easily creating everyday objects with this material and provides a new perspective on the way so much of our world is manufactured.
My first experience with plastic-making was the RTV Moldmaking and Casting class at TechShop. The class was taught by Tom Twohy, a TechShop veteran, and the perfect person to introduce a complete beginner to the material. Tom spent a large part of his career doing custom molds for masks, toys, and other inventions. Not only does he have an incredible knowledge of plastics and materials, he’s been at TechShop since it first opened its doors, and he has a great perspective on how people learn. His passion for creativity and the endless possibility of plastics is infectious.
Masks made by Tom Twohy. More on his blog.
You can go on YouTube or Wikipedia and learn the process for RTV (room temperature vulcanization silicone) moldmaking – building a molding box, mixing the silicone with the catalyst, proper pouring technique, but you can’t be infused with passion and inspired imagination without being taught from someone like Tom. His insistence on careful preparation and his emphasis on precision contributed to a unique tacit learning experience. He made the standing time (the time required to let the mold and casts dry) an opportunity to show off some of the projects he’s recently completed: a mask mold, a new case for his phone, and a RTV plastic replica of a GI Joe doll. Each project emphasized a different way the process and material could be used: the mask, to show us how he personally made a living off of molding, the phone case, to give us an example of a very practical use, and the GI Joe doll to show the extreme detail the molds are capable of. He also took the opportunity to explain other classes and tools that utilize plastics, such as injection molding and vacuum forming.
Experimenting with three methods of waterproofing the motors on the OpenROV (left to right): no waterproofing, Silicone Conformal Coating, Silicone Spray
By the end of the night, my mind was swimming with new ideas for molding and vacuum forming. Surprisingly, my next experience with plastics would be outside any of the topics and uses we discussed in class. The very next day, during a design meeting for OpenROV at TechShop with Eric Stackpole and Zack Johnson, Eric expressed an pressing issue that needed resolving: finding a way to waterproof the brushless motors used on the vehicle. Eric had a number of other design challenges on his plate, so Zach and I took this one on. Zach had a few ideas, the best one being seeking outside advice. After the meeting, we walked around TechShop and talked to a few other Dream Coaches and Shop members that Zack suspected had more experience.
Sidenote: This is by far my favorite thing about TechShop: the culture and community there. Every single Dream Coach knows the skills and experience of all of the other staff, but also, most of the members, which represents a large and diverse knowledge base. The tools are nice, but the magic is in the community.) Soon we had a series of hypothesis, most involving different types of silicon sprays, and that afternoon, Zach and I started some experiments to see which, if any, would solve our waterproofing problems.
Zach continued (and expanded) on the experiments over the weekend. The experiment centered around Silicone Mold Release Spray and Silicone Conformal Coating. Zack wrote up a fantastic report on the results, which you can read here.