As raw material prices surge and manufacturing cost pressures intensify, ‘consumables’ are often the very first target for cost reduction in many mold and parts machining facilities. Among these, the hundreds of liters of Electrical Discharge Machining (EDM) fluid required for EDM machines present a noticeable difference in unit price, making it incredibly tempting to opt for ‘low-cost oils’ that are cheaper by even just a few cents per liter.

However, while it may look like costs have been successfully reduced on paper for the purchasing department, expenses that are several times larger are leaking out in real-time on the shop floor. Today, we are going to thoroughly break down the ‘hidden maintenance costs’ that are so easy to miss when you only compare the initial unit price of oil in the EDM process.

1) Hidden Cost 1: Cost Explosion Due to Frequent ‘Filter’ Replacements

Because electrical discharge machining (EDM) is a process that erodes metal by melting it with electricity, it inevitably generates an enormous amount of fine metal dust and carbon sludge (debris). This is where the ‘Settling Property’—the most significant performance difference between premium EDM fluids and low-cost products—reveals itself.

• Premium EDM Oil: Rapidly settles the debris to the bottom, keeping the machining area clean and minimizing the amount of sludge being pumped into the filter.
• Low-Cost EDM Oil: Due to poor settling properties, debris remains suspended and floats within the fluid. This highly contaminated oil flows directly into the filter.

What is the result? When using low-cost oil, the rate at which expensive paper or cartridge filters clog becomes two to three times faster.

For example, suppose a factory that previously used 4 filters a month (200,000 KRW) at 50,000 KRW each experiences a shortened replacement cycle after switching to low-cost oil, forcing them to use 10 filters a month (500,000 KRW). This means an additional 3.6 million KRW simply evaporates annually per machine on filter costs alone. Ultimately, you end up paying significantly more for the extra filters than the money you initially saved on the oil.

2) Hidden Cost 2: Shortened Oil Lifespan and Exorbitant ‘Waste Oil Disposal Costs’

Low-cost EDM oil has extremely poor oxidation stability, making it highly vulnerable to the high-temperature electrical sparks (arcs) generated during machining.

• Degradation progresses rapidly, causing the oil to turn pitch black and emit a foul odor.
• Viscosity increases sharply, which degrades flushing performance and significantly slows down the machining speed.

Ultimately, this leads to a situation where the oil fails to meet its normal lifespan (typically 1 to 2 years), and the entire volume must be replaced in just 6 months. EDM machines require a massive amount of fluid per change, usually measured in 200L drums. Not only do you have to bear the cost of purchasing the oil twice, but the exponentially rising eco-friendly waste (waste oil) disposal costs also fall entirely on the factory’s shoulders. The financial loss from machine downtime, as operations must be halted to change the oil, is just an added burden.

3) Hidden Cost 3: Electrode Wear and Increased Defect Rates Due to Secondary Discharges

When debris fails to settle properly and remains suspended in the oil, normal electrical discharges between the electrode and the workpiece are disrupted. Instead, sparks jump to the floating debris, causing what is known as a ‘secondary discharge’.

This leads to the following critical quality degradation:

1. Decreased Machining Speed: Energy is dispersed to unnecessary areas, lengthening the time required to reach the target depth.
2. Degraded Surface Finish: Surfaces that are supposed to be smooth end up pitted or scorched black, leading to a sharp increase in post-processing (polishing) time.
3. Wear of Expensive Copper/Graphite Electrodes: Abnormal electrical discharges quickly erode the electrode tips, driving up the already high costs of electrode fabrication.

Conclusion: Buy ‘Productivity,’ Not Just the ‘Unit Price’ Per Liter

EDM fluid is the lifeblood of the mold machining process. If the “blood” (oil) becomes murky and contaminated, the entire machine falls ill and grinds to a halt.

With over 30 years of accumulated technological expertise in metalworking fluids, Dyna Solution Co., Ltd. firmly rejects the race to the bottom in simple low-price competition. Our lineup of high-purity synthetic EDM fluids is engineered to resolve your factory’s chronic filter clogging issues and drastically reduce long-term costs, driven by exceptional settling properties, high oxidation stability, and a high flash point (fire safety).

Are you inadvertently paying hundreds of thousands of won in monthly filter replacements and massive defect penalties just to save a few hundred won on the immediate unit price of oil?

Consult with the experts at Dyna Solution today to receive a comprehensive diagnosis of the hidden costs in your EDM line and start achieving genuine cost reduction.

Dyna Solution Co., Ltd.
Industrial Lubricant Solution
E-Mail : dyna@dynachem.co.kr
Web : dyna.co.kr/en/