Mold making for cheeses

Yesterday I made a cheese mold, yes, a mold for a mold that makes milk mold. A cheese mold. I thought I might share with you how I made it. The type of cheese mold I was making is a basket mold that can be set on a press for making Tomme style cheeses. You will see from the pictures that it has a slight taper. The dots that you see will be guides for me to put the holes in the finished cheese mold once the plaster mold is removed from the cast piece. 

First things first. I threw an original. It is solid and upside down (When the plaster is cast the clay that is touching the throwing bat on the wheel will be the opening). Allowing for final shrinkage the piece measures 8 1/2" at the top of the mold and 8" at the base with a height of about 4". It's finished dimensions should be about 7 1/2" wide at the top and 7" at the base with a height of 3 1/2". I'm working with about 12.5% shrinkage. Divide any wet dimension by 87.5 to get your final dimensions.

Next I needed to divide the piece in two for a two part mold. Now the cast pieces coming out of the mold will not be in two parts. I am only doing this to make it easier to get the finished pieces out of the mold earlier in the process before they start to warp. 

I used an old plastic lid from a defunct container as a divider. This will keep the plaster from running into the second part.

Next I built up a ring of clay around the 1st part and inserted the second part of my mold walls. I use metal roof flashing. It is cheap and flexible. It comes off my molds very easily and clay sticks to it, making for secure mold walls! A blow out when working with 6 or more pounds of plaster is a nightmare to clean up!

Here you can see the mold ready to be poured with plaster. I use a very simple plaster mixing ratio 3:1 that is 3 pounds of plaster to 1 quart of water. This can be broken down to smaller increments like 1.5 pounds and 1 pint or larger quantities like 9 pounds and 3 quarts, super simple.

For this mold I started out by mixing 6 pounds of plaster and once I poured it realized I needed a little more so I mixed up an additional 1.5 pounds and poured it in as well. 

I use hot water when I mix up plaster and an immersion blender or a stick blender. This gives me about 5-8 minutes of working time, which is more than enough time to mix more and add it in before it sets. I can usually remove a piece from the mold after about 15-20 minutes.

Here is the second half being set up for pouring. I put in a key hole on the top and bottom of both sides of the first piece. I usually use a coin for this. Depending on the size of the mold it can be a penny, a dime, a quarter, whatever works! Also, before I pour the second piece of the mold I use mold soap. This is a product I buy. I have tried many other types of soap and find that mold soap is worth the small amount of money and time it takes to track it down.

Finished mold ready for clean up.

Here you can see the key's that I put into the mold. This allows for a nice seating of the two pieces.

On the mold itself I use a metal rib to clean up the joint. This will make it easier to clean each piece coming out of the mold. Remember, the better you make the mold the better the pieces come out and the less time you have to spend working each new piece.

Here is the final mold. I use a sure form tool to clean all the edges of the mold before it starts to get hard, usually within the hour. Once it set's to its final hardness it is tougher to clean up. As you can see from the mold I try to make the mold with about 1 1/2" of plaster around the mold to get even walls when casting. One other thing to note is that I do not force dry the plaster! It will calcine the plaster and make it a worthless mold. Let it air dry in a warm room for about a week (at least here in the Northwest). At that point you can use it. I will cast these next week with porcelain and show you a finished product. 

Now that the goats are freshening I will be making some awesome Tomme style cheese this spring!