Are you looking to optimize your aluminum machining process and save money? Alcohol as a coolant is an alternative that has been used for decades in machining aluminum. It reduces operating costs, improves cycle times, and is a much easier coolant to work with than traditional oil-based coolants. This blog will give you insight into optimizing aluminum machining and the advantages of using alcohol as a coolant.
Types of Coolants and Lubricants
When machining, there are three different approaches to cooling and lubricating a cutting tool. The three most common systems are flood cooling, air cooling, and mist cooling, or minimum quantity lubricant (MQL). Each system has advantages and disadvantages depending on the application and user needs.
Flood Coolant
Flood cooling is the most common system. This system consists of a recirculating system that floods the cutting tool with water and oil-based coolants. These systems are highly effective in keeping the tool cool, flushing out chips, and allowing efficient cutting parameters. They are best suited for applications with larger-diameter cutting tools, machining steel, or applications when a large amount of material needs to be removed from the stock material. The main benefits are increased tool life and the removal of chips and debris from deep pockets or channels that reduce problems like tool breakage. Also, you can use flood coolant in various applications and materials.
A flood-based system’s main disadvantage is that it can be expensive to operate and maintain. Machine downtime is required to clean filters and maintain the system. Additionally, the coolant needs to be replenished over time and is environmentally hazardous, so proper disposal adds more cost. Typical flood coolant solutions can also pose high-risk environmental factors, including bacterial infections from airborne mist caused by improperly maintained filters and fluid quality.
Another disadvantage is that sometimes, due to the massive spray, you cannot see the cutting in the material, so an issue may not be detected immediately, causing a loss of machine time. Finally, since oil is used in the flood, the entire envelope of the machine tool and your parts will be covered in a residue that requires machine cleaning and is often a secondary step for washing your parts.
Air Cooling
Air cooling sometimes called a ‘Cold Air Gun’ system, utilizes a focused frigid air stream at the tool, cooling the tool and removing heat. This application works very well on softer materials such as plastic or composites. It also can be effective in drilling applications because the high air volume can penetrate deep into the hole and assist with difficult chip evacuation. It is also environmentally friendly and easy to maintain the system because you are not dealing with any coolants.
The main disadvantage is that these systems do not lubricate the tools, so cutter wear is more prominent than with coolant. You are also limited to materials that are only efficient for machines using this process. Sometimes, the extreme temperatures used in the process can impact tolerances or create undesired conditions, such as material fracturing. These systems are found on router-based machines that are not enclosed and cannot contain a flood-based system.
Minimum Quality Lubricant
A minimum quantity lubricant (MQL) system is becoming more common in the machining world and offers some unique advantages over the other two systems, depending on your application. The system is comprised of a high-pressure air stream combined with a minimal amount of lubricant to reduce friction and heat at the cutting tool. The coolant is dispensed so minimally that it’s hard to see during machining.
The Advantages of Using Alcohol as Coolant
Minimum Quality Lubricant systems are highly effective at blasting out chips and debris from the cutting channel without all the high maintenance costs of a flood-based system. These systems require little maintenance, and the costs for coolant can be significantly lower due to the minimal amount used.
When machining non-ferrous materials like aluminum, denatured alcohol such as Ethanol (like isopropyl) can offer many benefits. Denatured alcohol means there are additives in the product to inhibit its use for distilling. One main benefit is that alcohol can remove high volumes of aluminum material. Due to its high evaporation rate, alcohol has a significant cooling effect on the cutting tool. Keeping the cutting tool cool will decrease cutter wear and improve feed rates during the cutting process.
Using alcohol in an MQL system will improve your cutting feeds in aluminum, lowering the cost of producing parts. Since the alcohol evaporates, no extra maintenance or cleaning is required for your machining system or parts. The parts come off dry and surgically clean. Blow off the part with an air hose gun and you are ready with no secondary operations. The oilless coolant also allows you to create work holding that you could not achieve with a flood cooling system. For example, the vacuum table system by DATRON is designed to work with alcohol cooling and will not work properly with a flood-based system. The water in a flood system would swell the permeable cardboard substrate, impacting tolerances and its ability to secure the part. Additionally, water would enter through the vacuum table system and destroy the mechanics of the vacuum pump.
The Disadvantages of Using Alcohol as Coolant
The main disadvantage of an MQL system is that it is not very effective in high material removal rates in steel. MQL is better suited for machining non-ferrous materials, such as aluminum. However, oil can be used in these systems for light machining in steel, such as engraving.
There are legitimate concerns about using alcohol due to its flammability and environment. You can mitigate these risks using proper precautions. The flammability of the coolant, in the case of Ethyl alcohol, has an inflammation temperature of 425 degrees Celsius with a flash point of 12 degrees Celsius. Simply put, you must have a spark or expose the spray to an open flame to ignite the coolant. Machining aluminum or other non-ferrous materials would never generate enough heat to ignite the coolant. Precautions such as never vacuuming any excess alcohol into a shop vac are also important.
This risk is low because the coolant is no longer present seconds after the parts are complete due to the high evaporation rate. A standard vacuum pump used with vacuum tables is a closed system with no risk of alcohol or vapors igniting in the pump.
Concerning the environment, the amount of alcohol emitted is so minimal that it is well within all safe environmental measures. DATRON can offer additional information regarding this data. DATRON uses an aeration fan on all our machines to disperse the evaporated product as an extra precaution. It even has a sensor that will only allow you to use the machine if the fan is operational. Understanding these risks and taking the proper precautions allows you to leverage the advantages of using alcohol in an MQL spray system.
DATRON has the MQL System for You
DATRON, with our gantry-style machines, only offers MQL systems. The Microjet is a 5-liter, or optional 10-liter tank, mounted on the back of the machine. Depending on the application, it will typically last an entire production shift. The canister is filled unpressurized with a funnel and takes only a few minutes to complete. The system is pressurized with standard shop air at 90 psi once it is full. A feeder hose runs through the machine. This hose leads to a pair of nozzles spraying a powerful jet at the tip of the cutting tool. You can purchase an optional 4-nozzle head for increased cooling in demanding applications. DATRON can reach its industry-leading feed rates in aluminum due to using alcohol as a coolant, our spindles’ high RPM rates, and our cutting tools’ unique geometries.
Considering that there are no coolant disposal fees, minimal system maintenance, and the elimination of secondary part cleaning operations, alcohol is a very economical solution for machining aluminum. With improved feed rates lowering your cost per part, it is also an effective option for optimizing your production process.
Lower Your Costs with DATRON – Contact Us Today!
Using alcohol as a coolant in your aluminum machining process offers a range of significant benefits. From reducing operating costs and improving cycle times to simplifying maintenance and enhancing part quality. With its high cooling efficiency, minimal environmental impact, and ease of use, alcohol is a game-changer. If you’re ready to optimize your machining operations and achieve better results, don’t wait. Contact us today to learn how DATRON’s advanced MQL systems and innovative solutions can elevate your production to the next level.