I found a Youtube video that someone made about creating sand from bottles. I decided to copy the simple design. The machine can be called “Chain Mill” or I’ve heard them called “Chain Flail” or “Flail Mill”
The bottles should be washed and the labels removed. If you don’t remove the labels you will have to pick them out later. The labels may clog the classifier screen too.
The Machine
To build the processing machine I used a 20 Lb propane bottle, some chain, and a long 3/8 inch rod. It was powered by a 2 speed 1/2 inch drill. (I tried with a low speed mixer drill but the RPM’s are too low). You need a drill or motor that can turn around 2200rpm.
The propane tank has it’s valve removed, which was a challenge doing ( maybe get an old one from a propane shop that couldn’t be re-certified). I then cut the tank in half and attached a hinge and used bungee cords to hold it shut. The cut edges were lined with door seal off a car from the wrecking yard. Attach 2 short links of chain to the bottom of the rod. make the chain shorter than the radius of the tank. I drilled a hole in the rod and used a bolt to attach the chains. That’s about it.
The Process
Safety Gear
- Dust mask
- cut resistant work gloves
- Safety glasses or a face shield
- Work coveralls
Smash the bottles to reduce their size. Wear eye protection and gloves! Drape a wet cloth over the container while using a metal spear, or just knock one bottle against another until you are left with one.
You can add plates and pottery too if you are just wanting sand to fill drainage ditches. This stuff will work on utility grade concrete.
Test the chain mill with small batches of glass at first. I found I could only fill it half-way to the hinge, otherwise the dust would start spilling out.
I experimented with adding small amounts of water to reduce the dust, which helped.
You a classifier screen, a fancy term for a sifting screen to sort out the different sizes of silica. Again, depending on what you want to do, it may not be necessary.
If building your own processing machine is not for you, there are ones you can buy, but they are NOT Cheap!
https://www.bottlecrusherus.com/ Their cheapest one north of $6000 US.