How To: Minimising epoxy waste
In the days of ‘Reduce, Reuse, Recycle’, there is always a way to minimise your leftovers. David Johnson uses his epoxy experience to offer his top tips on working with these disposable consumables.
As the saying goes, you have to break a few eggs to make an omelette. When it comes to epoxy, you have to throw away a few tools to make a repair.
I consider myself frugal when working with epoxy. Through experience, I have learned just how much mixed resin/hardener/filler I need to undertake the work I have planned. It’s amazing how much work one squirt of resin and one squirt of hardener will do. With good work planning and estimating, it’s clearly possible to be efficient and not throw unrecyclable waste epoxy in the bin.
But what about the other so called ‘consumable’ products that we have at our disposal?
I have seen people all over the world using everything from yoghurt pots to sawn-in-half milk bottles, to baked bean tins to washing up bowls as mixing pots. But if you want a good job done, you should use the best pots.
Many proprietary plastic pots have a rebate in the bottom which allows them to be blown off the mould during manufacture; unreacted epoxy caught in this little reservoir will seriously compromise your work if you brush it on. What’s more, although it is possible to throw your clean yoghurt pots in the recycling bin, you can’t do this when they’re full of cured, hardened epoxy.
So, good quality, straight sided, flat bottomed pots of the same size should always be part of your epoxy toolkit. They can be used many times simply by carefully breaking out the cured waste by rolling the sides of the pot and pushing on the bottom. They are also recyclable if they break. In fact, this is a good opportunity for quality control, because if you have a residue of unreacted epoxy in the corner of your pot, you are simply not mixing for long enough.
Good hardwood stirrers and tongue depressor-type wooden sticks make mixing much easier as you can get right into the corner of the pot – remember that residue! What’s more, they cost barely anything.
I make a hardwood stirrer last for the day and for a few more jobs simply by wiping it clean on my gloves before disposing of them.
My mixing stick of choice is the WEST SYSTEM® 804 plastic tongue depressor. This makes filleting and residue clean-up so much easier. With their rounded and chiselled ends, cured epoxy just breaks off. For something so small and costing so little, they are brilliant.
Plastic squeegees also cost very little and are sturdy enough for many re-uses. When they get worn, they can be sharpened and straightened with a lick from a hand plane, or recycled to make great windscreen ice scrapers!
While we’re on the subject of re-usable tools, sturdy plastic roller trays are another wise investment. The cured epoxy simply breaks out with a twist. Leave the cured epoxy in the tray until you are ready to use it again, as the broken out waste leaves a super-clean tray beneath.
The WEST SYSTEM 800 foam rollers are essential for distributing even coatings of mixed epoxy. The thin foam prevents the epoxy from curing on the roller.
One 7″ roller should last for an entire single coat on even a large osmosis treatment. A top tip to preserve the roller frame is to leave the epoxy in the foam sleeve to cure before breaking the sleeve in the centre with a hammer – if done carefully the frame will last a long time.
Brushes are something of an extravagant disposable tool. I have yet to discover how to clean a brush and dry it without the bristles retaining the faintest residue of epoxy and becoming rigid. Cleaning solvents like acetone and vinegar all seem to render a brush unusable once dried.
So, cheap disposable brushes are a must. I use a lot of the WEST SYSTEM 803 glue brushes as these are inexpensive and get the job done. Make sure to crimp the metal bridle with some vice grips as this stops the hairs falling out into your work.
I stopped using latex gloves many years ago, replacing them with blue nitrile gloves. These give much better protection and are non-allergenic. I like to think I am frugal with them – it helps if you wear two pairs at once and then the top pair slips off without turning inside out – but in the end it is all about avoiding skin contact with epoxy. They are a necessary and very important disposable item that provides good skin protection and a clean result to your work.
All of the above might help you save you money, limit your waste, and be kinder to the environment. I like to think that the more epoxy you apply, the longer that component might last. So don’t throw it away – apply it to your work!
Find out more about safe epoxy disposal.
David Johnson is Technical Operations Manager at West System International. His regular contributions to epoxycraft include: The best way to avoid mistakes when using epoxy, Amine blush: What you need to know, and many more.