Recommended Coolant
We recommend using Dowtherm SR-1 Heat Transfer Fluid in your chiller and water-cooled spindle. While many good-quality brands are available, all are designed to be mixed with water. Even automotive antifreeze, which contains ethylene glycol and anti-corrosion additives, can work.
However, Dowtherm fluid is specifically designed for this application.
The recommended mixture is 50% distilled water and 50% Dowtherm SR-1.
This mixture reduces spindle corrosion and improves the thermal efficiency of your chiller and spindle.