Oct 17, 2026, 7:42 PM
Email: info@CNCmarket.ca
Phone: (825) 454 66 97
PRO399
Made to order
EASYCUT PRO399 Universal Metalworking Coolant incl. Yellow Metals, 55 Gallon Drum
PRO399-55Made to order
CA$2,363.18 excl. taxes
Retail price as of 10.17.2026
Retail price as of 10.17.2026
EASYCUT PRO399 is a universal water-miscible coolant for shops with a large share of brass, bronze and copper. Special additives keep copper from dissolving into the emulsion, so the coolant stays stable and parts stay clean even when yellow metals make up most of the work. It also machines steel and aluminum, so one coolant can run across the shop. Mineral-oil-based, about 26 % oil, boron-free.
Brass, bronze and copper chips slowly dissolve into an ordinary emulsion. The copper builds up month after month: the coolant turns greenish, the emulsion loses stability, parts stain, and the copper ends up on steel parts and machine surfaces. In a shop that cuts mostly yellow metals, this is usually why the coolant has to be changed early.
In a 28-day lab test, beryllium-copper swarf was kept in each coolant at 8 % in water of 20 °dH, and the copper content of the emulsion was measured every week:
| Copper in the emulsion, ppm | 7 days | 14 days | 21 days | 28 days |
|---|---|---|---|---|
| PRO399 | 20 | 23 | 21 | 23 |
| Conventional semi-synthetic coolant | 101 | 121 | 159 | 347 |
PRO399 picked up a little copper in the first week and then stayed flat; the conventional coolant kept rising and ended about 15 times higher. The pH of PRO399 held steady too, from 9.3 to 9.1 over the four weeks.
Run PRO399 from 7 % for general machining — a refractometer reading of about 5.4 °Brix. The refractometer factor is 1.3: multiply the °Brix reading by 1.3 to get the concentration. Add the concentrate to the water while stirring, or use a coolant mixer, and top up with premixed coolant; the coolant calculator works out the amounts.
Make-up water should be between 5 and 30 °dH (about 90–530 ppm hardness); a fresh emulsion stays stable up to 80 °dH.
| Type | Mineral-oil-based, water-miscible |
| Mineral oil content | about 26 % |
| Viscosity of the concentrate at 20 °C | 103 mm²/s |
| pH of fresh 5 % emulsion | 9.2 |
| Refractometer factor | 1.3 |
| High-pressure coolant (above 40 bar) | Yes |
| Free of | Boron |
| Contains | Amines |
| Shelf life | 12 months unopened, stored at 5–40 °C |
| Origin | Germany |
The 55-gallon drum is the working size for a shop running PRO399 across its machines: at 7 % it makes about 780 gallons of working coolant, at a lower price per litre than the pail. To try it on one machine, take the 5-gallon pail; for central systems and larger shops, the 270-gallon tote has the best price per litre. Small variations in colour and odour between batches are normal. Safe handling is covered in the SDS.
The refractometer factor or Brix factor for CNC fluid concentrate is a multiplier used to convert the refractometer readings (Brix scale) into the actual concentration of the emulsion (concentrate + water).
