How To: How to mix small amounts of epoxy resin and hardener
We’ve all had those times when we only needed a little bit of epoxy. Maybe to fill in a chip, fix something that’s broken in the house or to glue something small together. How do you mix a small amount, properly? West System International’s very own technical advisor, Hamish Cook, explains all.
I’ve had a couple of phone calls from people recently saying that their epoxy isn’t curing. This always surprises me because WEST SYSTEM epoxy is ultra-reliable and will always cure if mixed properly.
When I get a call like this, my first question is: how are you measuring the resin and hardener? To which they usually reply that they only wanted a little bit of epoxy. So they measured with, say, teaspoons – maybe five teaspoons of resin and one of hardener. Or even two and a half teaspoons of resin to half a spoon of hardener.
In theory, this sounds fine (it follows the five-to-one ratio) but in actual fact, spoons will never give you the accuracy you need for a decent cure. There’s always residue left on the spoon, so you don’t know how much you’re really mixing together. Plus, you’re relying on getting the measurement right by eye, which is never a good thing.
Instead I recommend four, more accurate, methods that will ensure a decent cure for any amount of epoxy – especially small amounts.
1. Mini pumps
The mini pumps we sell are always the first place to start. The pumps in the WEST SYSTEM® 303 special ratio Mini Pump range are designed to mount directly onto the resin and hardener containers and have been calibrated to deliver an accurate working ratio.
However, you’ll get around 25g of product from using these – which means you’ll still have wastage on some really small projects. If that’s the case, you could try one of the other measuring methods below.
2. Graduated measuring/mixing cups
We supply these in our 101 Mini Packs. However, any small graduated cup will do – such as the really little ones that come with cough medicine. As long as it’s graduated and really clean, it should work.
If you really want an ultra-small amount, you can use a syringe. WEST SYSTEM® 807 and 807B syringes are great for this job. The 807B syringe can even help you measure just 6ml of epoxy resin if that’s what you’re after.
4. Digital scales
Don’t forget, you can also weigh everything out with an accurate set of digital scales.
Whatever method you use for measuring out your resin and hardener, as long as the mix ratio is correct the epoxy will cure – adding more hardener won’t make it cure quicker. An accurate ratio is the key to making it work!
Want to learn more about dispensing with mini-pumps? Watch our video here.
Interested in learning more tricks of the epoxy trade? Have a look at our complete list of Trade Secrets.