Sunday, January 24, 2016
Imperial Highway III
The sign is, alas, gone now.
In any case, the Imperial Highway project is turning into my big exercise in learning how to achieve clean casts. I've made about two dozen casts now, and they continue to have problems. Air bubbles, holes, overflow...and then there's my experiments with dying the Smooth-Cast 300 with something other than the pigments the manufacturer recommends (because I don't have time to order those and have them shipped).
The side pieces are being done in a two-piece box mold, made the classic way; lay up one side with clay, pour, flip and remove the clay, spray thoroughly with mold release, and pour again. I didn't remember to add pour spouts when I was laying up the clay, but that didn't matter so much; I needed to cut over a dozen vent holes (and I'm still getting trapped air in the cast).
The top deck is a one-piece mold, and in that one, the main issue is that if I don't have the mold perfectly level, and pour to exactly the right depth, the final piece doesn't have the right (or even consistent) thickness. I took the skin off my thumb trying to sand these pieces flat.
So I've been repairing with auto putty (not Bondo, but the nead-able two-part stuff) sanding and trimming, and gluing in the super-magnets that hold the final assemblies together strong enough to support lead miniatures for table-top play but that allow them to be packed flat for slightly better transportability.
As additives, Pelican black ink appears to be working. As long as I mix it into the B part of the casting compound. Or was it the A part? The primer, on the other hand, didn't adhere properly and I spent a nice hour removing that with acetone. There goes my illusion that I could assembly-line cast and paint all of them on Saturday, and have time Sunday to start cutting out the access ramp (which, assuming I get that far, will be done in a shell mold).
I picked up several cans of Tamiya model spray (I've had good results with it in the past), Model Master colors for the stonework and detailing (which I will probably add to with my old college set of acrylics), and some cheap brushes to stick in the enamels. There's also a little blood on them as well (see above re my injured thumb).
Ah, if only TechShop was more convenient. I'm tempted to move messy projects like this out to my work space, but I'm still waiting for things to firm up a little around there before I start asking favors.