How to Fix Broken Molds

About: I'm a nerd who loves to geek out with makeup. And books, series, movies, you know.

One of the bummers on working with plaster to mold stuff is that it breaks, either if you’ve dropped it, or put a weird pressure on it, or even by simply demolding it.

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Step 1: Burlap

You can use burlap in between layers to add strength to it.

Step 2: Mixing the Plaster Like a PRO

You can mix the plaster properly by adding water FIRST, and dust the plaster on top UNTIL all water is absorbed and it ends up looking like a dry soil, then mix it throughly to use.

Step 3: Prepping for Mold

You can avoid cut areas that would lock a mold.

Step 4: Intensify Plaster's Curing Process

You can spray some water after the mold starts to cure, then cover with a plastic, so the reaction of the plaster will "kick in" stronger, and the mold ends up firmer (Rob Freitas tips).

But sometimes, your mold just breaks! And that sucks!

Step 5: Products & Tools

The misshapen can be fixed by mixing some more of your plaster, and just patching the holes. However, as I do work the minimum as I possible can with plaster, hence I hate the mess it makes, I’ve come up with a fairly obvious solution: using a paste that is close in chemicals of your plaster to patch those holes.

Since I use plaster of paris or stone in most of my molds (mainly because this is what I can find on the country I live), the paste that would best work together is Spackling Paste, which is made to fill holes in walls, and stuff like that.

So basically what you'll need:

• Spackling paste;

• Clean Spatulas; and

most important,

• Broken Mold.

Step 6:

In this video you can see exactly how simple it is to fix a mold with it. And mind you, my mold was in a dreadful state.

Per usual, I do let my molds dry for 24 hours so any water on the mold can evaporate. You don’t necessarily need to do this, but I do see a difference on the casting of the products when I wait.

Another alternative to spackling paste is: Acryl 60 mixed with the plaster of choice (it works with ultracal, so I guess it works with others).

I hope you found this post useful. Let me know if you do break your molds as often as I do, and how to you usually fix them!

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Laura x



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