WEST SYSTEM 300 Mini Pump Set

Made job easier easier to measure

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!

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.

I used West System products as a rotor mechanic and it’s a good to go company.

Just as I expected

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.

Easy, accurate mixing. Pumped quantity is small enough for the small jobs, but large enough that getting a large batch accurately measured is also a breeze.

I didn’t buy these at first because I didn’t see the need to have these just for mixing the right ratio. However, I now love the convenience of just pumping to add more to my mix whenever I need it.