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Hey folks, just wanted to let you know that the Calnaga Castings store is open and filling orders again. We were closed for a couple of years due to a demanding work assignment, but the store is open again. The correct web address is www.calnaga.com. I’ve seen it stated incorrectly in various threads. We also have a Facebook page, Calnaga Castings. Happy Modeling Steve Perry/Calnaga Castings

For many years a friend of mine and I were collaborating on his model of a carnival in N-scale (that is a model train scale of 1:160). He built the models and I animated and illuminated them. The scene resides on a pair of NTRAK modules which we display at the local model train shows. Here is an older video showing the original midway. Couple of years ago my friend wanted to expand the midway by adding another couple of feet to the module set. One of the rides was going to be bumper cars. Since there are no commercially available models of N-scale bumper cars I offered to make them for him. I decided to make a master and cast them out of resin. The carnival is set in late 1960s or early 1970s. I first gathered some photos of bumper cars. I then got some rough dimensions. These are the prototype on which I loosely based my model. I started with a piece of acrylic (Plexiglas) which I cut to the scale length and width of the car. The scribed mark denotes how high the car needs to be. Then I planned on how to get to the shape I needed. Next, using a saw, files, and dental grinding bits in a Dremel tool, I removed all the material which was not the bumper car's body. I then scribed the front grille and a trim line around the body. Finally, I polished the body using an 4-grit fingernail polishing stick. The steps which I didn't photograph (I should have) were milling machine operations: Using a 0.025" mill bit I made a hole for the electric pickup pole in the rear and holes for 0.025" styrene rod I would use for the headlight pods. Then I glued in the styrene rod and trimmed it to represent the headlight pods. I then separated the car body from the rest of the acrylic piece. Then, using a piece of 0.032" acrylic sheet, I made the "rubber bumper" base for the car. Base glued to the car body (using a methylene chloride based liquid cement). I then glued the master pattern to a flat acrylic base. Using masking tape, I created a dam to hold the RTV rubber and ... ...poured the liquid rubber into the cavity. Once the rubber hardens, I remove the tape and pull the rubber mold off the master. It is a simple 1-piece open mold. I just poured the resin until the cavity was full. Here is the first molding popped out of the mold. I also went a little nuts: I photoetched the steering wheels. Then I soldered them to a steering column made from a 0.010" brass rod. Steering wheels ready to be painted black. A finished bumper car. The body and the bumper areas were airbrushed with Scalecoat II paint and the seat and grille/headlights were brush painted (under a microscope). Here is a couple on a Nickel .... And a whole gaggle of finished models. Before you ask, yes, I had to cut off the feet of the figures before I plopped them in the cars. I'll try a 2-tone paint job on the next batch I'll make. I am totally nuts for making them this detailed, since they will be placed inside a covered arena, viewed from about 2 feet. But I just couldn't help myself... Here are the bumper cars placed on the track. And a night shot. Here is an overall view of the new part of the midway. This is an early photo, before the people figures and final detailing was done. This is a newer video showing the entire midway.

Thought I would try to resin cast some brake rotors for a PT Cruiser convertible I'm working on, as the wheels are open and absence of rotors is quite noticeable. I am planning to use a rotor from a 1998 Firebird kit as a master, and use a one piece mold. Looking for advice on how to mold the center hole open so that the rotor will slip over the wheel.