INTRODUCTION TO THE PUMPS
You will notice that each of the pumps has writing on the top: thus, the largest pump, imprinted with the word "Resin" on it naturally fits the can of resin.
The two remaining pumps both have the word, "Hardener" imprinted on top. However these pumps are not interchangeable with each other - the screw tops on each correspond to different types of hardener, and the pumps are pre-set to different measurements.
The "Hardener" pump with the smallest screw top fits onto the West System 207 OR 837 Clear Coating No Blush Hardener (Round can with blue Label).
The "Hardener" pump with the larger screw top lid fits the , (West System 206 Slow Hardener or 205 Fast Hardener, or the East System 834 Intermediate Hardener or 833 Fast Hardener).
Please note that the West System Pump set comes with different attachments depending on the size of the can - simply switch the tubes on the pump with the replacement of the appropriate size.
USING THE PUMPS
Once you have placed the pumps onto the appropriate container, mixing the resin and hardener becomes a simple job.
All that is needed is to press down on each pump ONCE = One pump resin for one pump hardener.
Using the pumps means that you do not need to worry about the correct 5:1 or 3:1 ratio that is listed on the can's label. The West System Pumps are pre-calibrated to give you the correct ratio required.
We have found the best way to mix the resin and hardener is to start with resin, then hardener, then resin and hardener again. This way you know that even if you have lost count of how many pumps of resin you've added, you always end on hardener, and will thusly have the right mixture.
Though some may have previous experience with polyester resins, we would like to highlight a major difference between the polyester resin and epoxy resins. Primarily, if you want the polyester resin to cure more quickly, it is perfectly acceptable to add more of the catalyst. This is not possible to do with the epoxy resin systems. Adding more than the correct measure of hardener will not make the epoxy cure quicker, it will only mess up the mixture and will result in the mixture not curing at all. Ever.