The wax parts I sent them looked like this:
Once the parts are on the tree it is time to 'invest' them. In production this is an automated process that repeatedly dips the tree assembly into a fine ceramic slurry and then lets dry. The composition of this material is important as it needs to transmit fine detail yet be strong enough to survive handling and thermal shocks. After several coats the wax parts now have a thin ceramic shell surrounding them. The shell is still uncured 'green' ceramic so is very fragile.
The parts look great and the smooth surface finish is a relief after all the work that went into finishing out the Makerbot mold patterns.
Now I need to find some time to put into machining both the fixtures and the parts. Now that these have come out so well I'll start the same process for the remaining 2 parts: the lower chassis crossmember and the front suspension mount.
Slowly but surely progress is being made!