Tools – West System – Poly Mixing Pot

Dispensing epoxy resin and hardener into mixing pots

Dispense the proper proportions of epoxy resin and hardener into a clean plastic, metal, or wax-free paper container. Don’t use glass or foam containers because of the potential danger from exothermic heat build-up.

DO NOT attempt to adjust the epoxy cure time by altering the mix ratio. An accurate ratio is essential for a proper cure and full development of physical properties.

Dispensing with Mini Pumps – Most problems related to curing epoxy can be traced to the wrong ratio of resin and hardener. To simplify metering, we recommend using calibrated WEST SYSTEM Mini Pumps to dispense the resin and hardener. Mini Pumps are calibrated to deliver the proper working ratio of epoxy resin to hardener. Pump one full pump stroke of resin for each one full pump stroke of hardener. Depress each pump head fully and allow the head to come completely back to the top before beginning the next stroke. Partial strokes will give the wrong ratio. Read the pump instructions before using pumps. Before you use the first mixture on a project, verify the proper ratio according to the instructions that come with the pumps. Re-check the ratio anytime you experience problems with curing.

Dispensing without Mini Pumps (Weight/volume measure) – To measure 105 Resin and 205 Fast Hardener or 206 Slow Hardener by weight or volume, combine five parts resin with one part hardener. To measure 105 Resin and 207 Special Clear Hardener or 209 Extra Slow Hardener by volume, combine three parts epoxy resin with one part hardener (by weight, 3.5 parts resin-1 part hardener).

The first time you mix epoxy

If this is the first time you have used WEST SYSTEM epoxy, begin mixing epoxy in a small test batch to get the feel for the mixing and curing process, before applying the mixture to your project. This will demonstrate the hardener’s open time for the temperature you are working in and assure you that the resin/hardener ratio is metered properly. Mixing epoxy in small batches is a good way to gain confidence in the mixture’s handling characteristics.

Learn more about epoxy batch size and cure speed in the article “That’s a Fact” by Mike Barnard in Epoxyworks #41.