One of the most non common-sense procedures, yet *most* important for the proper performance of a water soluble metal working coolant is, simply, Oil In Last or OIL. Common sense says "put the quart of coolant concentrate in a 5 gallon pail first, then fill the pail up with water to get a better mix, solution" Wrong.. By adding the water TO the coolant, it is most likely that a significant portion of the mix will be an invert emulsion as opposed to a regular emulsion, which is what we want/need! An invert emulsion occurs when the coolant is overwhelmed by too much water; water is a very agressive solvent and if enough is present can completely surround the oil molecule, creating an 'invert' emulsion. The problem with an invert emulsion is that it can cause corrosion, greatly reduce the effectiveness of the coolant and create the possibility of mocrobial growth and its side affects. So, the procedure is: take a five gallon pail and fill it with water to the 5 gallon level, then add the appropriate amount of coolant, slowly, stirring as it is added. Then you will have the perfect emulsion and the maximum performance from your metal working coolant.
George Morrison
George Morrison