*Myth Busting: Plastic Tool Handles From Milk*
I read an article on creating a natural plastic from milk that could be used to construct knife and tool handles. I set out to prove or disprove this "myth" with a lil' FNV!
What is Casein? Milk is a bunch of protein particles held in suspension. Milk protein is 80% casein and 20% whey protein (the stuff muscle heads take for body building) When an acid is added to milk, it chemically forces the protein globs to coagulate and form a chain of protein molecules called a polymer. Casein is a natural plastic that was used in the early half of the 20th century to make buttons and pens and as a substitute for expensive and exotic materials such as ivory.
How do we make Casein plastic? First I poured 3 cups of milk into a pot and placed it on the stove on high heat. I then added 2 tsp of distilled white vinegar for each cup of milk (a total of 6 tea spoons full). I stirred this and immediately saw the separation of the curds from the whey. The whey is the cloudy liquid that is left behind and the curds are the solid material that floats to the top. I placed a paper towel in a strainer and poured the pot through it to capture all the solid curds. I placed the curds in a measuring cup and determined that I had obtained almost one full cup of curds from the original 3 cups milk.
I then gathered all the curds and wrapped them in a paper towel to squeeze out all excess liquid. I then kneaded the ball in my hands. This seemed difficult at first as the ball had a tendency to break apart but after a few minutes it took on a doughy consistency. I wanted to use it to make a handle for a tool and I had thoughts of removing the handle from one of our steak knives but I foresaw how well that would go over with my wife. I headed for the basement and grabbed an old dewalt sawzall blade. I notched the top with a grinder so the blade didn't slide out of the handle.
I formed the ball around the blade into the likeness of a handle. The handle became an ergonomic impression of my hand. I made two of these hand saw combos as you can see. I let them dry for 3 days before trying to use them. They were very comfortable handles but they just didn't feel sturdy. I was able to cut through both wood and metal using each saw but the handles started to crack after about 10 minutes of hard use.
In the end, I feel that it is plausible to use this material in a pinch but with the wait for it to dry and the delicate nature of these makeshift handles, I would just as soon whittle the handles out of wood and use some duct tape. It would be less labor intensive and more rugged.
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