The author purchased a pattern set at a flea market and decided to have it cast at a close by foundry, "Mystic River Foundry" in Mystic, Connecticut. The foundry owner invited the author to come on the casting day and observe the step by step process, from pattern to finished castings. The 52 picture slides document the process very well.
The pattern set looks like a small gear box, smaller but similar to the gear box required for one of the hand operated grinders in the Advanced Projects post. I mention this to point out that it is not really as difficult as it looks.
Sharon Hertzler the owner, who doesn't mind getting her hands right in there, does a great job. A good example to all those critics on line, who like to deride the hobby casting process every chance they get (I think the term is "grow a set"). Having a big guy like the foundry man around to help with that big crucible sure helps a lot, ha ha.
To download this file click Mystic River Foundry. 2 MB - pdf