WEST SYSTEM 300 Mini Pump Set

These pumps are perfect for mixing epoxy and make it easy to get the ratios correct. I appreciate that the cans and pumps are designed so they are mistake proof from mixing up pumps with resin and hardener.

I have been using the West System 5:1 epoxy system for over 15 years, and have been extremely satisfied with the consistency and results....so much so that I decided to treat myself to this new set of metering pumps. I do a lot of small batches and these pumps make that task so easy!

These worked perfectly. I was irresponsible and did not do a "test pour" to check if the proportions were right. I literally came home from work, slapped these things onto the 105 resin and 207 hardener, went through half a gallon of 105 and 1/6th gallon of 207. No problems with the curing/hardening process. I did see someone else comment negatively about how the plastic was brittle and broke for them after a couple pumps. Because of that I was cautious at first but after a while I saw that point was null and void. I was not gentle with these suckers, I just went to town on them. Included hardware notes: This comes with the 3 nozzle heads you see in the picture, 1 is for the resin, 2 are different sizes for hardener containers of differing spout sizes. There is also extension tubing included for if you need to fine tune the length of the nozzles.

Easy to identify which is which for resin or hardener and the pump out the right amounts.

Using a pump makes using epoxy SO MUCH EASIER. One of these was to replace one ancient one that gave up the ghost. I would only recommend using this brand as they last SO LONG.

UPDATE 16 Feb 2015: I purchased another set of these pumps since the compound in my other containers turned yellow and I didn't want to mix any of the old stuff with the new compounds. This second set is much better than my first set. They work smoothly and do not loose the suction like the first set I had. Therefore, I upgraded this review to four stars. See the original review below: This is the pump kit specifically designed to meter the correct amount of chemical for the West System epoxies. Their system is a 3:1 ratio. These pumps seem to be well made, sturdy, and come with different length feed tubes to fit two different size cans; very convenient. But in operation, they don't work so well. During the upstroke, they occasionally suck in air from the seal at the top of the pump. This results in the next pump delivering an incorrect amount of chemical. An incorrect amount of chemical results in weak epoxy. This problem seems to happen more with the pump used in the hardener can. I tried several pumps from each chemical squirted into separate cups as a test. I then poured the chemicals back into the cans when done. I found that if the pump handle is very carefully pumped down while applying a slight lateral pressure in one direction, then I get more reliable results. Then doing the same procedure on the upstroke. However, it did not work 100% of the time. I talked with a friend of mine, who has been working with West System epoxy for several years, and he said it has been a problem for years. I would have expected a better product from West System considering how great their epoxy is. The only other option is to pour the chemicals in graduated cups to get the right mixture, but this is not as practical if you are mixing several small batches.

These things are great. So much quicker and less messy than measuring out each component. The pump delivery volume is not described very clearly and so can be misunderstood. Here are results of measurements I made on pumps I purchased. The large pump delivers about 0.66 fl. oz. of resin per full stroke. The 207/209 hardener pump delivers about 0.22 fl. oz. per full stroke; mixing this with the resin yields a total of about 0.88 fl. oz., with a resin to hardener volume ratio of about 2.95. The 205/206 pump delivers about 0.12 fl. oz. of hardener per full stroke; mixing this with the resin yields a total of about 0.78 fl. oz., with a resin to hardener volume ratio of about 5.45. With this information, you can figure how to use these pumps with other brands of epoxy. Just be sure to get it right!

Works great if used often, stoped working after being stored in a cool dry place for 9 months with out use.

They do what there supposed to do.