Many WEST SYSTEMÂŽ Epoxy users take their new Mini Pumps out of the bag, mount them on the resin and hardener cans, and begin dispensing and mixing epoxy without ever having read the instructions. Most use them for years without a problem. Of those who do experience a problem, weâve found that it most often could have been prevented byâyou saw this comingâreading the instructions. The instructions offer simple steps that you can take to help assure that every batch of epoxy you apply to your project will cure properly and reach its maximum strength.The ratio of each pair of pumps is controlled by the installation of a clip, that limits the stroke (and volume) of one or both of the pumps. All pumps are carefully inspected during this operation and during packaging. But the final test of a pumpâs performance canât be made until it is actually pumping resin or hardener, a test we canât perform and still keep the 300 Mini Pumps affordable. The ratio verification test described in the instructions confirms that both pumps are dispensing the correct volume and that the ratio of resin to hardener is within a critical narrow range.Getting the most out of Mini PumpsNow that you made the right decision and bought the pumps, hereâs how to make the most of your purchase.When you first install the pumps, check to make sure the resin pump is ready to use. Hold the white cap that screws onto the can and the clear plastic pump barrel and make sure they are screwed together snugly. You will also want to check on this from time to time.Priming the pumps before the first use is simple but important; the instructions in the package explain how to do this. You will want to check the prime if the pumps been sitting for a long time, or when changing cans.
Thatâs right, when changing cans. No need to buy new pumps every time you buy new cans of epoxy. Store the pumps right on the cans and when you run out of WEST SYSTEM Epoxy you can move your pumps to the new cans of resin and hardener.
If the pumps have been sitting on the cans for a while they may develop a crust on the end of the spout. Hardener pumps particularly seem to do this. The crust is easily cleaned away: just break it off and wipe the spout. You can use warm water to clean the hardener pumps and acetone or denatured alcohol for the resin pump, if needed.
Use only full pump strokes and do not pull up on them; let them return on their own. Alternating one stroke of resin and one stroke of hardener eliminates the need to count strokes and reduces the time spent waiting for the pumps to return to the top of their stroke. Slow pump return can be an issue when using epoxy in cooler weather when the epoxy becomes âthickerâ (actually, more viscous as our chemists would say). Try to keep your resin and hardener warm even if what youâre working on isnât. Mix your epoxy indoors if youâre working at low temperatures in the garage. In the boatyard, an empty cooler and a shop light with an incandescent 15-watt bulb will keep your resin and hardener nice and warm.