I described the Ponoko laser cutting service and the Misumi semi-custom parts service. As nice as those are, sometimes you just need to make something out of a chunk of aluminum with a good old fashioned machine tool. Of course you can try to remember how to do that yourself, or find a really handy friend who can do it for you. Most of the time, I use emachineshop.com.
Here are some parts I made using the eMachineshop service.
Here are the eMachineshop parts combined with the Ponoko parts and the Misumi parts to make the completed assembly.
There are two super cool things about eMachineshop. First, they offer a free computer-aided design tool you can download to your PC. It is quite intuitive for doing anything that is basically 2 1/2 dimensional. That is, if you can think of the part as a slab of something from which you will remove material, it’s really easy to design using the free tool. Second, with one click you get a binding price quote from emachineshop to make the parts. How cool is that? So, you can try different materials and approaches to see how the cost is influenced. When you’re happy with the design, you click “order” and you get the parts in the mail a few days later. Basically, emachineshop gets bids from a bunch of suppliers, mostly outside the US who work directly from their part files. They are an intermediary between you and shop. I’ve used them a few times and it’s worked perfectly each time.