This week we took a wee trip to a plastics moulding company!
The company (which I won’t name for reasons which will become clear later on…), specialised in dip moulding, rotational moulding and Vacuum forming. There were a couple of things which in particular attracted my attention.
One thing I found really interesting about the trip was the dip moulding process, until Thursday I had no idea that dip moulding was a thing. I had never heard of it before, at all! Yet when I was at the factory I saw them dip moulding numerous products that I recognised, the concertina covers for gear sticks, handle grips and the covers for seat belt holders- these were all items I’d seen, but embarrassingly I had never considered how they were made. It turns out dip moulding is also used in the manufacture of other flexible products such as balloons and, surprisingly, condoms…
The process itself was great, it looked a bit like traditional candle making. Metal moulds are heated and then ‘dipped’ into tanks of liquid PVC (The PVC itself isn’t hot – mind blown!). Then the mould is simply lifted out, cured and then left to cool before being taken off its metal mould.
The thickness can then be changed by changing the length of time the mould is in the PVC, the temperature of the PVC and the temperature of the mould. What is fascinating is that the PVC begins to cure the minute it touches the mould, which is why changing the above can change the products thickness.
The last stage is then to just tidy them up a bit, trim the edges and remove the end if necessary.
Another thing I found really interesting was how the moulds are actually made.In this particular factory there was a single man in an upstairs workshop who was responsible for mould making. If a mould was simple, he just turned it on the lathe himself. For more complicated shapes he had to make them out of sections of wood so that they could be send to a foundry to be cast out of metal. His precision and skill was outstanding, and it was crazy to think that one man was so integral to the success of the entire factory. One wooden master he showed us was made out of 20 individual pieces of wood!
On a less fun note I was also, unfortunately, struck by the working conditions in the factory. It was the level of plastic fumes that got me. Obviously fumes are to be expected in a plastic factory but this seemed like too much for people to be working in all day without any protection. I was only there for an hour or two but left with a headache. There were men and women working beside vat of molten plastic that didn’t need to be. It seemed odd to me that the women who were tidying up the finished moulded parts should be sitting in such a warm, smelly and noisy room when their work could easily be done elsewhere. It also seemed bizarre that despite the signs all over the factory that ear protection must be worn, very few of the men working on the machines or the women beside them were wearing any at all. Surely it is not healthy for people to be working in such a toxic environment for so long. I couldn’t help but imagine that the health of many of these people would suffer as a result of their time spent among the noise and the fumes and that it’s likely that no one will even bat an eye or consider it some kind of injustice.
Ultimately my visit to the moulding factory was very insightful, although certainly not in the way I had expected.