If you’ve done any silicone mold making, you know to treat the material like liquid gold. Silicone ain’t cheap. That’s a fact of life. If you end up mixing too much of the goop for your current mold making project, you could be scrambling for some way to use it that doesn’t waste the dollars you’ve just poured into a cup.
What do I do Bill!?
The first thing you could do is to just let the silicone cure in the bottom of your mixing cup. Then, when you peel it out, you’ll end up with a reusable silicone dish that you can use for stirring Bondo or epoxy. So handy!
If you have a touch more forethought, you could make another, smaller mold! I usually keep tiny, neat looking hardware around. You might call this “hoarding”, but I say it’s “planning for future builds”! For example, large hex screws can be really neat additions to prop projects. So, if I’m mixing up some silicone and I’m worried I might have a little extra, I’ll put the screws in some clay to make a jury-rigged mold box before I stir up the silicone.
Then I go ahead and pour the big mold that I had already planned on making. If I end up with extra goo, I scrape it into the tiny clay mold box that I made.
Once the silicone has cured, you can liberate your hex screws and use them for another project. You’ll be left with a handy little mold to use whenever you need to make a bunch of hex screw heads.
Bonus: You have a mold to keep around for when you’re casting larger things. If you have any extra resin, throw it into this mold and make copies to keep on hand! Now you’re saving wasted resin too!
I’ve ended up with a small library of these kinds of molds over the years. Whenever I find a neat little piece of hardware, I’ll clay it up and keep it around for whenever I’m mixing up a batch of silicone.
You can also chop up left over silicone to use as registration keys or filler for new molds!