A couple of months ago I introduced Jay Lees, General Manager of Nu-Cast Inc. of Londonderry, NH who created a set of aluminum Ridgewing body frames using an investment casting process. I recently came across a couple of interesting pictures from that project.

This first picture shows freshly cast aluminum body coming out of its mold. To review, the investment casting process involves first creating a foam or hollow 3D-printed model of a part, then dipping it in several layers of finely ground aluminum oxide, then cooking it in a furnace to burn out the model and harden the coating, then pouring in molten aluminum, then removing it from the mold, and then cleaning it up. One very cool aspect of the process is that the time from pouring in the molten aluminum to taking the raw casting out of the mold is only a couple of hours.

It is obvious that a whole lot more got molded than the frames. This massive column in the middle and the various sprues connecting it to the separated frames are the plumbing for the aluminum pour. Aluminum is cheap, but even one bubble in the finished casting can be very expensive.

Here are the finished frames after Jay cleaned them up.