Lesson 121 – Zebra Skimmers Product Features

In this training module we will focus on the Zebra products that are the most popular within each coolant maintenance protocol.

This overview touches upon product strengths, specifications and all other details are in the full line catalog or online.


It’s good practice to measure coolant concentration to help eliminate problems associated with low or high concentration values. Given that our customers are mostly practical in nature, Zebra provides an instrument that is accurate yet easy to use.

Zebra offers optical refractometers. This means that you use it by putting a drop or two of your coolant on it and read the value on its incremental scale by looking through its eyepiece. This optical scale is called Brix, which was designed for sugars in solution measurement.

brix refractometer

Metalworking fluid users will need to check their coolant product data sheet to find the “Refractometer Factor” for their coolant. They will then multiply this factor by the reading on the scale to determine the concentration value.

Machinist Mixer

Mixing coolant by hand is not practical, and consumes valuable labor time–time better spent making parts. Zebra offers the Machinist Mixer, which meets the needs for most coolant mixing applications where short distance mixed fluid delivery is acceptable.

venturi mixer

The Machinist Mixer uses water pressure to create a venturi, or vacuum, inside its chamber to suction concentrate up its standpipe and mix it with the incoming water.

The dial on the top of the mixer connects to a needle within this chamber. This needle makes the venturi larger or smaller to provide heavier or leaner output values. Four full turns of this dial open the venturi to its maximum value. Concentration percent is not a direct reflection of the number on the dial. You will need to verify the output, at any given setting, using a refractometer. The Machinist Mixer is the most rugged of its kind currently on the market.


Consider the Oxygenator the rain on a bacteria’s parade. We also call these units bubblers, because they make bubbles.

The bacteria we’re fighting within the sump thrive when their oxygen supply is gone. When the machine is shut down for the night, the pump stops circulating coolant, traces of tramp oil float to the surface, and the oxygen supply to the fluid is cut off. This is the best time for bacteria to grow.

Oxygen is diffused into the coolant using an Oxygenator, thus discouraging bacterial growth. Simple, yet very, very effective. Especially for those machines that run less than three shifts per day, including weekends.

The Oxygenators are inexpensive and similar to aquarium pumps, but we use oil rated tubing and sintered bronze air diffusers that won’t degrade in coolant.

Odor Control Tablets

Ever hear the line, “Gee, your sump smells terrific?” We didn’t think so! Neither have we!

Even with preventive coolant maintenance, some sumps still smell. The coolant might be quite old, sometimes it’s the configuration of the tank, or they’re being used as spit cans.

Zebra’s Odor Control Tablets are not deodorizers, which would just put a perfume over the originating foulness. OCT works chemically to rebalance the coolant’s pH. Remember, bacteria emit acid and it’s these acids that you smell. When we balance the pH back to where it should be, the smell goes away. Safe as directed, easy to use, and a must for Monday morning odor.

odor control tablets

Sidewinder Tube Skimmer

Skimming tramp oil is half the battle when it comes to clean and healthy coolant. Given the limited access that machine tool builders provide for their sumps, some consider the ZVA Sidewinder to be half the battle in achieving this goal.

Developed originally for the Mazak Quickturn in 1994, it has become a solid staple in Zebra’s mechanical skimmer fleet. The ZVA8 Sidewinder is a tube skimmer that works well in tight spots due to the flexibility of the tube.

Its compact design and zero vertical access (ZVA) feature, allow it to install on almost every machine sump known to mankind. Only a small opening is required to install the tube to draw off the fluid’s surface.

The Sidewinder tramp oil skimmer offers flexibility in terms of tube length. They are available in various reach sizes, from 8” all the way to 95”, in 3” increments.

Long reach tubes make it suitable for deep tank or underground pit applications.

Long reach tubes also allow it to skim elongated tanks, where oil is thinly spread across a vast surface. The washer on the tube may be clamped to the opposing end of the tank, at the low fluid level. It will now skim the entire surface, no matter the level of the fluid.

Since the tubing used is made for oil, the Sidewinder is not rated for use with coolant concentrations below 5%, nor on wash water. Some customers still use it due to space issues, but are warned that the tube will not be warranted, as it will prematurely degrade.