Before filling in the resin, I glued the wings back on. I first used superglue gel. However, the gel I used was old, and wouldn't kick :( Bummer. The car is cast in 1630, which has some very odd properties. It doesn't really sand normally, and glue tends to take to it poorly. I ended up gobbing on a ton of 90 second duco epoxy, which seemed to hold the wings in place. Once the epoxy had set, it was time to pour in the resin.
The other reason I decided to fill the pieces with resin was to provide a stable, flat underside. Being that the pieces are warped, the underside edge is not even. It lists to one side. I want that to be flattened out so that when I start adding on the detail pieces to the underneath, they will be on a flat, even, level surface. Since resin pours as a liquid, it will naturally form a smooth, flat surface.
At this point in the project, I made another executive decision. My goal was to get these two cars cleaned up and then remold them. Considering the material that this was cast from, the poor state of the details, and the fragility of the wings, I decided that I will rebuild the cars, mold them, cast up a brand new car, and use that casting to do a final build up.
In these pictures, you can see both cars filled and sanded. Before I poured the resin, I build up "dams" around the car by applying a lip of masking tape and sulpher free clay. This was to make sure that no resin ran over the edges on some of the "low" spots. As it turned out, this was a great idea as the bottom of the grey car was VERY uneven. Anyhow, once the resin was poured and set, I took a sanding block and took down some of the high edges left over. At the end of this step, both cars have nice flat bottoms.
So far, this project has taken me about four hours from start to this point. I spent a lot of time examining the undercarriage, and trying to match thicknesses of styrene. My plan is to scratch build many of the parts found on the underside, and research is a necessary part of that.