Ok, had a little goof up..
I made a mold, and apparently went about things the wrong way, so I have an RTV mold, which is basically three hex shaped holes. This should be ok, if I can attach something flat to it. The question is what if anything will actually stick to a cured mold? I made the mold in a coffee can lid, I figure if I can just get the lid to stay, I should be golden. And advice, comments, derisive laughter?
Thanks.
RTV: Attaching it to something
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RTV: Attaching it to something
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Shinnentai
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Something pourous. Cloth is good. Use spray adhesive (or other glue that won't soak the cloth) to glue cloth onto a flat piece of material. Then "glue" the mold to the cloth by mixing up a little more mold rubber, and letting it soak into the cloth surface before setting the mold atop the cloth. When the new rubber cures, it will become one with the old rubber, with the cloth acting as a structural binder to the flat surface.
Alternatively (and this is the fasterbettercheaper preffered method) is to make a mother mold base for your cured rubber to fit into. To do this, set up a clay wall around the rubber mold (with about a centimeter of clearance on all sides), then pour in plaster to about a 1cm depth, and allow it to self-level to a flat surface before it sets. Once it's set (don't need to wait for it to dry, just untill it's suffiiciantly solid to continue), lay the rubber mold on top, and pour plaster into the margins between the sides of the rubber and the clay walls. This gives you a plaster "tray" you can place the rubber mold into to hold its (flat) shape during casting,
The latter is the universally preffered method, as it is not only cheaper & easier, but also allows you to disengage the rubber from the solid flat surface at will (makes for much easier demolding of your final castings).
When you say "in a coffe can lid", what do you mean exactly? Is the rubber being held on by the rim/lip of the lid, or just by surface tension? If the rubber were to leave the lid, could it be set back into it the same way it was originally? If so, the lid is already your mother mold. The rubber doesn't usually have to be bonded to the substrate, in fact it's better if it's not (see reason above).
If the bottom of the rubber is truely flat already, you can just set it on the benchtop without a mother mold, provided it's thick enough (or the mold cavity shallow enough) that the weight of the liquid resin in the cavity won't deform the sides of the mold.
Alternatively (and this is the fasterbettercheaper preffered method) is to make a mother mold base for your cured rubber to fit into. To do this, set up a clay wall around the rubber mold (with about a centimeter of clearance on all sides), then pour in plaster to about a 1cm depth, and allow it to self-level to a flat surface before it sets. Once it's set (don't need to wait for it to dry, just untill it's suffiiciantly solid to continue), lay the rubber mold on top, and pour plaster into the margins between the sides of the rubber and the clay walls. This gives you a plaster "tray" you can place the rubber mold into to hold its (flat) shape during casting,
The latter is the universally preffered method, as it is not only cheaper & easier, but also allows you to disengage the rubber from the solid flat surface at will (makes for much easier demolding of your final castings).
When you say "in a coffe can lid", what do you mean exactly? Is the rubber being held on by the rim/lip of the lid, or just by surface tension? If the rubber were to leave the lid, could it be set back into it the same way it was originally? If so, the lid is already your mother mold. The rubber doesn't usually have to be bonded to the substrate, in fact it's better if it's not (see reason above).
If the bottom of the rubber is truely flat already, you can just set it on the benchtop without a mother mold, provided it's thick enough (or the mold cavity shallow enough) that the weight of the liquid resin in the cavity won't deform the sides of the mold.
"Chaos is found in greatest abundance wherever order is being sought. It always defeats order, because it is better organized."
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-Ly Tin Wheedle