Making Parts
I titled this generically so it could evolve and be added to, but I thought folks might get a kick out of seeing the process involved with making replacement parts.
I am casting a replacement part for Cathy (Mizkaki) for her Boye Needle Round display. Her's is missing the arrow in the center that is the handle to turn it with. Mine came with one in perfect shape. so, RTV it is.
RTV = Room Temperature Vulcanization. (Cures at room temp, no heating required)
It is a two part rubber compound that can not only cure at room temp but once cured can handle the temperatures involved with molten pewter (around 200 F) I have used this method to cast brass/bronze/copper but it fries the mold in a cast or two. For those metals I usually use sand casting.
Here is the Original Part in the plastic case we use to pour the mold into. We first put down a layer of soft Sculpey clay to simulate the second half of the mold. At the top right you can see the baked Sculpey that acts as the form for the pour cone. (once we add the rubber and it dries, that part will be hollow)
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Here is Heather mixing the goo...
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the goo (No matter how yummy this looks DO NOT TASTE IT)
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poured into the mold cavity
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and this morning after getting most of the bubbles out last night and letting it set up.
(it is cold and damp out so it will take a little longer to fully set)
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When Heather takes the 1st half of the mold out later today, I will post more pictures showing the prep and pouring of the 2nd half.