Step 6: Finished! (and FAQ)
I know you have questions. There are always questions. I'll try and answer as many as I can and provide as many resources for you to explore if you're still curious about all the parts:
- Q: Where did you get the silicone? How did you cast it?
- A: I got mine at Douglas and Sturgess in SF, but you can order it online at smooth-on, freeman, and even Amazon. It tends to be rather expensive but has a long shelf life and is a great mold making material. You can even cut up old silicone molds to use as a filler when you cast new ones. The casting process was super simple. I just built a box around the wax part with some paint stirrers and poured the silicon on. I've got some more detailed tutorials about casting silicone here and here.
- Q: What kinds of wax did you use?
- A: What I cut out was a hard, easily machinable, fine grained wax called machinist's wax. It's pretty cheap and is an awesome material for CNC especially if you want to test out something super fast before doing the final version in metal. I get mine from Progress Tool. To do the duplicates, I heated up red casting wax from Douglas and Sturgess in a coffee cup in a toaster oven and poured it into the silicone mold.
- Q: How do you get metal parts cast?
- A: Feel free to build your own home forge to cast metal parts. I don't really have the time or inclination to do all that just for some buckles, but it's still on my list of life goals. You can mail wax parts to almost any small investment casting studio and they'll duplicate them in metal. You lose the wax (that's why it's called lost wax) but you get back a really high resolution metal part. Be sure to call and ask what kind of metal they cast, if there are any limitations on the dimensions of your part, how they cast it (if you have to make special allowances for sprues) and try to supply them with as much information as you can so they can give you an estimate on cost. I have used JR Casting for several of my projects and have been really impressed. They cast silver, gold, brass and bronze there. The cost of your part will vary on how big it is (how much space it takes up in their casting container or flask), how much labor it takes to get it set up, and how massive it is (how much metal they have to pump in.)
- Q: What is Techshop? How do I get access to a CNC?
- A: Techshop is a kind of gym for nerds. You sign up for a monthly membership and they give you open access to a huge selection of industrial machines, hand tools, workshop space, and cool people. For the more complex machines like the Tormach you have to take a class. Getting time on CNC machines is kind of hard. Although the technology's becoming cheaper and more ubiquitous every day it's still not common to find a CNC machine available to use at the rec center or your local library. Chances are you won't be able to get time on one unless you buy one, build one, have a TechShop near you or know how to get in touch with machine shops and beg your way inside.
- Q: What is CNC? What is the Tormach?
- A: CNC is short for Computer Numerical Control. This means a computer handling something by numbers, coordinates, or vectors. Often this is used to talk about machines that are driven by this architecture. Wikipedia has some pretty good articles. If you really want to learn more there are really good videos on youtube and forums all over the place. Instructables even has several CNC projects as well as Thingiverse and RepRap. The Tormach is a fairly powerful CNC machine, especially at its low price tag of $7000. It lives at TechShop, but was previously employed on Prototype This.
- Q: Steampunk? Bioshock?
- A: Steampunk is an ethos and fashion trend that has really caught on with geeks and makers from across the globe. It's essentially an interpretation of an imagined past where steam technology was never replaced by electronics, therefore you get mad ideas like steam powered helicopters and spaceships. Bioshock is a videogame made in this style. It's a bunch of fun to play.
- Q: What is brazing?
- A: I used a torch and some bronze filler rod to weld on the rings and pin that make this a belt buckle. The process is called brazing. It happens at a lower temperature than steel or aluminum welding but is still very strong.
- Q: Why did you cast it in bronze? I thought brass was the quintessential steampunk metal.
- A: I originally wanted it cast in brass. I like the green verdigris brass gets with age. Unfortunately a lot of metal casters won't get many brass orders so will wait until they can fill a whole flask with parts before casting. I decided I didn't want to wait the month or so it would take to get it cast in brass so I just opted for bronze, which is apparently more in demand.
- Q: How do I get my own?
- A: You can't. At least, you can't now. You'll just have to suffer in envy.