For metering larger quantities of 105 Resin and 207 Special Clear or 209 Extra Slow (3:1 ratio) Hardeners. The 306-23 Metering Pump will reduce mixing time and waste on large projects. A carrying handle allows you to move the pump where the work is. Reservoirs hold one gallon of resin, one quart of hardener. Dispenses approximately 0.5 fl oz of resin/hardener per pump stroke (about 1 qt per minute).
Ratio Verification with 306-23 Metering Pump
WARNING! Check the ratio of resin to hardener dispensed by the pump before using the epoxy on your project. Recheck the ratio periodically or if you later experience incomplete or unusually fast or slow curing.
The most accurate method of checking the ratio is by weight. Dispense at least five strokes of resin and hardener into separate, pre-weighed containers. Weigh each of the samples on a balance or gram scale to determine the net weight of each. Divide the net weight of the resin by the net weight of the hardener to find the ratio of resin to hardener. The ideal or target ratio and the acceptable ratio ranges for each resin/hardener combination are shown in the charts below. Deviations beyond the acceptable range in either direction will result in an incomplete cure and significant weakening of the epoxy.
The ratio can also be checked by volume. Pump at least five strokes of resin and hardener separately into the two graduated measuring cups included with the pump. Set the cups on a level surface to accurately determine the volume of resin and hardener, in either ounces or milliliters. Divide the volume of resin by the volume of hardener. The ideal or target ratio and the acceptable ratio range is shown in the chart below. The ratio by volume is different than the ratio by weight because hardener has a lower density (greater volume per unit of weight) than resin.
This check can be done with any two identical, narrow, cylindrical containers. Measure the levels of the dispensed resin and hardener in the containers with a ruler. Divide the measured height of the resin by the measured height of the hardener to find the ratio. Monitor the resin/hardener ratio by examining cured epoxy left in mixing cups. If the residue is not sufficiently hard after the appropriate cure time has passed, recheck the pump ratio.
Acceptable ratio ranges for WEST SYSTEM 3:1 ratio Resin and Hardeners (207 & 209) with the 306-23 Epoxy Metering Pump
|Resin/Hardener||Weight Ratio||Volume Ratio|
Learn more about mixing epoxy in large batches by reading Big Batch Mixing Methods by Tom Pawlak in Epoxyworks 9.