Why does surface rust appear on stainless steel rulers used in Wire EDM WEDM?

Surface rust deposits on an MXRuler used in Wire EDM WEDM are usually external contamination from rusted workpieces, contaminated dielectric water, or poor water quality. These deposits are contamination sticking to the ruler, rather than corrosion originating in the ruler itself. The rulers are made from corrosion-resistant 440C stainless steel.

Check for these common causes:

• High water pH, which is alkaline rather than acidic. Test with a suitable water test kit and replace the water if needed.
• Tap water containing minerals or metals. Use softened or deionized water as appropriate for the machine.
• A low water-quality meter reading, below the original recommendation of 50 kΩ. Check the deionizing bottle and confirm the meter units and required operating range in the machine instructions.
• Rusted or contaminated workpieces introducing deposits into the tank.

Deposits on ground reference surfaces often wipe off. Counterbores, screw holes, and other areas with low water flow can collect more contamination. Scrub these areas at the end of each day, dry the fixturing, and monitor water quality regularly. If deposits cannot be removed or the reference surfaces are damaged, contact MaxxTooling for an assessment.