Foundry - Polygons in Bronze: Part 5
Bubbles, voids, patchy spots... A terrible cast
I used this poor cast as a way to practice some wax carving. I would've remelted it into our large wax pot, but I didn't want to contaminated the pot with specs of plaster dust that are embedded throughout the surface and interior of this wax.
This wax was much softer than I imagined it would be.
Strange banding throughout the surface
Here is our class's wax pot and pouring station
The plaster that made up my mother mold took much too long to dry... so much so, that it was still not completely dry when I poured my first wax cast into this mold. As you can see in the pictures, the surface is covered in banding lines, voids, bubbles, and other imperfections (the ear even broke off in the mold...). I believe that some of this was caused by my own impatience causing me to rush this cast, but I also think that much of the surface imperfections stem from the wax cooling too fast in some parts of the mold. Overall, I am of course to blame for all of this, but it was certainly a learning experience.
I couldn't re-introduce this wax into our large vat of molten wax without possibly introducing flecks of plaster that crumbled off the shell and into the open mold cavity where they were embedded into the wax itself. So, to not completely waste the material, I used it as a practice canvas to see how I wanted to carve the surface. I tried brushing hot wax onto the surface with a paintbrush, carved with all sorts of wax carving and linoleum carving tools, and also looked at creating a more abstract texture in place of the faux fur texture I planned on using.
Following this cast, I went and made a new mother mold. This time I fabricated it over the next 2.5 days using a material from Smooth-On called "Free Form Air". It is a very lightweight epoxy putty. To make this mother mold, I cut some slits into the registration keys (which I also trimmed slightly) and made some walls out of note cards and masking tape. The mold shell would be made up of 5 separate pieces that would then be bolted together to keep the silicone in place. I had to wait for each section to dry before making the next, liberally applying vaseline to the surface of the silicone and epoxy to keep things from sticking to each-other.
