Full-Synthetic CNC Coolant Technical Material Specification
Comprehensive technical specification for full-synthetic CNC coolant used in Canadian fabrication, woodworking, and machining operations. Covers properties, sizing, machinability, defects, and handling guidelines.
Material Overview & Common Uses
Full-synthetic CNC coolant is a high-performance, water-soluble metalworking fluid formulated without mineral oils. It consists of synthetic lubricants, corrosion inhibitors, biocides, and surfactants designed to provide exceptional cooling, chip flushing, and rust protection. Unlike semi-synthetic or soluble oils, full-synthetic coolants offer superior heat dissipation, extended sump life, and reduced bacterial growth. They are transparent, allowing operators to clearly view the cutting zone, and are ideal for high-speed machining, grinding, and turning operations on ferrous and non-ferrous materials. Common applications include CNC milling, turning, drilling, tapping, and sawing in Canadian job shops, production facilities, and woodworking operations where coolant mist and cleanliness are critical.
Core Technical Properties & Sizing
| Property | Value / Specification |
|---|---|
| Concentrate pH | 9.0 – 9.5 (as supplied) |
| Working solution pH | 8.5 – 9.2 (at recommended dilution) |
| Refractive index | 1.0 – 1.5 (varies by formulation; typical for 5-10% dilution) |
| Viscosity (concentrate) | 100 – 300 cSt @ 40°C |
| Specific gravity | 1.02 – 1.08 g/mL (concentrate) |
| Flash point | >150°C (concentrate, closed cup) |
| Corrosion protection | Passes ASTM D4627 (cast iron chip test) at 5% dilution |
| Recommended dilution range | 3% – 10% (typically 5-7% for general machining) |
| Hard water stability | Stable up to 400 ppm CaCO3 |
| Biocide type | Formaldehyde-releasing or isothiazolinone-based (per formulation) |
| Shelf life (concentrate) | 12-24 months in sealed containers, stored between 5-40°C |
| Packaging | 20 L pails, 205 L drums, 1000 L IBC totes (standard Canadian industrial sizes) |
| Freeze-thaw stability | Concentrate may thicken below 0°C but returns to spec after warming and agitation |
Machinability, Tooling & Feeds
| Parameter | Recommendation / Effect |
|---|---|
| Cutting Speed Increase | 10-15% over straight oils due to superior heat dissipation |
| Tool Life Extension | 20-40% over straight oils |
| Ferrous Materials Concentration | 5-8% to prevent rust |
| Aluminum Concentration | 4-6% to avoid staining |
| Titanium & High-Nickel Alloys | 8-10% for enhanced lubricity |
| High-Pressure Systems (>1000 psi) | Requires anti-foam additives; synthetics can foam excessively |
| Woodworking Dilution | 3-5% to prevent resin buildup on tooling |
| Compatibility | Check machine tool seals and way covers; may cause swelling of older elastomers |
Common Defects & Quality Control
| Defect | Cause | Remedy |
|---|---|---|
| Foaming | Excessive concentration, high-pressure delivery, or soft water | Reduce concentration or add defoamer |
| Rancidity | Bacterial growth due to low concentration, poor housekeeping, or stagnant sumps | Maintain concentration, use aeration, and add biocide |
| Rusting | Insufficient concentration, low pH, or hard water | Increase concentration, adjust pH with buffer, or use deionized water |
| Staining on Aluminum | High pH or chloride content | Reduce pH or switch to aluminum-specific formulation |
| Separation or Gel Formation | Freeze-thaw cycles or contamination | Discard if not re-homogeneous after agitation |
Quality Control Checks: Daily refractometer reading to verify concentration. Weekly pH test. Monthly biocide dip slide test for bacterial count (<105 CFU/mL acceptable). Quarterly tramp oil removal. For incoming concentrate, verify refractive index, pH, and clarity against COA.
Storage, Handling & Racking Guidelines
Store full-synthetic coolant concentrate in original sealed containers in a dry, temperature-controlled area (5-40°C). Avoid direct sunlight and freezing. For 20 L pails, stack up to 3 high on sturdy pallet racking; for 205 L drums, store on spill containment pallets, single layer only. IBC totes should be stored on level ground with secondary containment. Always use dedicated pumps and transfer equipment to avoid cross-contamination with other fluids. When mixing, add concentrate to water (never water to concentrate) to prevent inversion. Use a mixing proportioner or pre-mix tank for consistent dilution. Dispose of spent coolant as per local regulations; many Canadian facilities use coolant recycling services. Label all containers with product name, concentration, and date mixed. For long-term storage, rotate stock FIFO. In case of spill, contain with absorbent pads and dispose as hazardous waste.