So beginning this step by step I want to test out all the various steps independently, so I can tackle each problem one variable at a time. I've been reading through a mess of books and other resources keeping my brain stirring around the ideas and hunting for image sources for the oval brooches. To begin with the simplest things first, I started with how to apply the period appropriate pinback findings. Generally these are constructed out of three tabs, two to act as a hinge and the third a bit longer to eventually be shaped to make a hook/loop. The designs I picked for the test cast are waxes things I've made in in the last year or so with a nice thickness and simple shapes. The bird is my version of a style that was found in Sweden (Image: http://www.flickr.com/photos/32404172@N00/6735308883 , Museam: http://www.luhm.lu.se/Main_eng.htm ) and the round brooch is just a simple line and dot pattern.
Here's the finished and touched up waxes showing their sprue forms and then, below, there's some pieces of my local clay, wedged, pliable and ready to go.
Two flasks ready to go, for the first firings I will be running these alongside a series of normal plaster flasks, the kiln firing for casting which is to ramp up in stages to 1300F and then back down to about 1000 to cast over the course of 6 hours.
Now the next wee adventure, there's much to be said for working in the right materials. So I poured out a sheet of beeswax about 3mm thick. I then transferred a rough tracing of the design to scale, on the wax by drawing over a piece of paper placed over the wax and tacked down in place.
This, when finished will be a replica of a belt end strap very much like this... " http://www.britishmuseum.org/research/collection_online/collection_object_details.aspx?assetId=968329&objectId=64687&partId=1 "
Building up the wax where the heads and beads will go gives me a good layout and helps the detail lines fall into place. I'm not inclined to obsess over each and every line but I'm getting the feel for this.
The wax was a bit gummy and would have been easier to work on if it were a bit colder, but it's now at a place that's good enough to try out some impressions. I've kept the design free of undercuts though if there are small ones the clay will actually be fairly forgiving, there's really nice plasticity in this earthenware.
Pretty good transfers in these, a few touch ups on the high points and a retracing of all the linework. At the same time I melted up some of the some more wax and formed a bowl for the first of the simple brooches that I want to carve, these are large beasties, about 11cm x 7cm.
Wax #1 is a mess, the sides were pulling in too much as it cooled, so I messed around (a bit too much), but things get better on the next pour. I pushed out the sides about 1/2 cm all around to give more allowance for shrinking.
Then, I did a clean pour and additionally to help fight shrinkage, I kept dripping wax into the middle without breaking the meniscus.
A collection of all the pulled waxes.
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