For casting (after extensive testing) I've found a mixture of 50 mL of warm water (or about 1/4 cup) and 7 1/2 Tablespoons (I use 5 flattened measures of 1 1/2 Tablespoons) stirred for at least 5 minutes (preferably until there are no lumps) performs well and produces sufficient mixture to easily fill the Wizard's Tower mold with some left over for other uses (see below). Mixing does tend to introduce a lot of bubbles, but this doesn't affect the casting if you are careful to tap the mold thoroughly and run a paintbrush along all the mold edges immediately after pouring.
After pouring, the mixture should reach toothpaste consistency after 30 minutes so you can scrape off the excess. After 1 additional hour you can remove the blocks from the mold (you can be rougher the longer you wait for the putty to set). The excess putty may be put to several uses, especially between 30 - 50 minutes after mixing. Once it has reached a toothpaste or thicker consistency, it makes a strong and highly effective mortar for bricks, producing a more natural look than normal gluing. Additionally, for any bricks or pieces that come out concave (you scraped too aggressively) you can fill in the concavity and either flatten it now, or let it dry and sand it down later. Lastly, if any air bubbles marred the cast and you have a light and steady hand, you can make impromptu repairs to it.
Merlin's Magic Hobby Stone (Grey) 10# $15.00 1 $15.00
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