How to make your own polythene bags
It’s generally recognised that making stuff at home is cheaper than buying it ready made. After all, you’re not paying for other people’s labour. Davpack sells clear polythene bags at prices you’ll find hard to match elsewhere, but it may be that you could make savings by making your own. Not being ones to deter an adventurous or entrepreneurial spirit, then, here’s our handy guide to help you get started.
Phase one: the raw materials
Obviously the first thing you’ll need is some polythene. Regular readers will know that this isn’t as easy as it sounds. Making the stuff is famously hazardous and is not to be recommended unless you’re very knowledgeable and/or very foolhardy. Nor can it be bought at your local supermarket, even if it’s a Tesco Extra. Happily, there are people out there who’ll be more than happy to sell it to you in resin form. Just put the right terms into a popular online search engine and you’ll come across them soon enough.
I ought to point out at this stage that these people are unlikely to be willing to supply it in small quantities, so if it’s only a few dozen polybags you need to package up some home-made sweets for a village fete, this probably isn’t a practical solution. Basically, if you can afford the ready cash and storage space to take a container load in one go, keep reading.
Phase two: extrusion
Once you’ve got your polythene, you need to extrude it. This will require a special piece of machinery which can also be sourced from the internet. I should warn you, though, it won’t be cheap.
Extrusion is basically the process by which your container load of resin is turned into the plastic film from which your polybags will be made. It does this by pushing the resin through a long barrel, while applying increasing levels of heat so that it slowly melts. You need to make sure you get your temperatures exactly right here, because overheating can cause degradation in the polymer and you wouldn’t want that; don’t worry though, your extruder should come with an easy-to-follow instruction manual that will make it all clear.
Once it’s been melted, the polythene has any contaminants removed by being forced through a screen, before entering the die. You set this to create the final ‘profile’ of the polythene. We’ll be needing it in a tubular form. You can also determine how thick you want your plastic to be here.
The polythene then needs to be cooled so that it keeps the shape you’ve just given it. Again, specialist equipment is strongly recommended. Putting it in the fridge won’t do, I’m afraid. You should now have what is essentially a very long piece of layflat tubing.
Phase three: conversion
A converter is basically a giant, automated heat sealer, in that it cuts and seals the film as it passes through. Some converters can do other clever and useful things, like perforating instead of cutting so your bags are on a roll, or even turning the film into grip seal bags. Obviously, if you do just want basic poly bags, then hand operated heat sealers could do the job, but given that you’re working with vast quantities of film here, it’s probably going to take you a number of years to work your way through it all.
And that, as Bruce Forsyth used to say on the Generation Game, is all there is to it! If you’re still keen, then may I wish you the very best of luck in your new venture.
The more rational among you will long have realised, however, that the above is only going to be practical if you need literally millions, if not billions of polythene bags. So, instead, why not just keep calm and carry on buying your bags from the UK’s friendliest packaging supplies company?
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