When equipment in tough environments like limestone mines needs maintenance, innovative solutions often emerge. Norman, a technical support specialist at Tormach, recently undertook a personal project to create a custom thread cleaner for his brother, who works in a Tennessee limestone mine. Using Tormach’s 1500MX CNC mill to cut steel, Norman built a tool to clean debris from threads on injection-molded plugs frequently used in the mine. In this article, we'll walk you through the step-by-step process Norman took when crafting this part for his brother.
The Challenge: Cleaning Threads in Dusty Conditions
The limestone mine's harsh environment often leaves threads clogged with debris, making it difficult to secure injection-molded plugs. Off-the-shelf solutions were not viable due to the unusual thread geometry. Norman tackled the challenge by crafting a custom solution. The threads, measuring 1 3/8 inches in diameter with an unconventional depth, required precise measurements and machining for a proper fit. To ensure accuracy, Norman machined a test plug before moving on to the final design.
Choosing the Right Material: Tool Steel vs. Stainless Steel
For the project, Norman used A6 tool steel, which was readily available in his shop. While tool steel offers excellent hardness after heat treatment, Norman noted that stainless steel would have been preferable for corrosion resistance in the mine’s damp environment. Nonetheless, A6 tool steel provided a robust material for this application.
Threading, chamfering, and facing on the Tormach 15L Slant-PRO
Norman began the process on the 15L Slant-PRO lathe, where he used conversational programming to complete rough turning, threading, and chamfering:
- Threading: Separate threading programs ensured precise tolerance adjustments.
- Chamfering: Chamfers were added to enhance thread engagement.
- Facing: While many machinists face first, Norman prefers to face last to achieve his desired finish.
Cutting Steel with Precision on the 1500MX CNC mill
The next step involved cutting steel on the 1500MX CNC mill. Norman used the machine to cut a 1-inch square drive and a pocket for a 1/2-inch ratchet. These features enable the tool to accommodate different drive systems, increasing its versatility. The 1500MX proved to be a powerful and precise solution for machining steel, showcasing its industrial-grade capabilities in handling tough materials with accuracy and consistency.
Final Details on the microARC 6
Norman finished the machining process on the microARC 6 rotary axis, where he added channels to create flutes for clearing debris from threads. These flutes, while not cutting edges, ensure effective removal of dirt and debris from clogged threads, making the tool ideal for harsh environments.
Heat Treatment and Finishing
After machining, Norman plans to heat-treat the tool to harden the steel. He will also apply a black oxide coating for corrosion resistance. While the coating may wear off in the demanding mining environment, it provides an initial layer of protection.
Lessons Learned and Final Thoughts
Reflecting on the project, Norman highlighted a few takeaways:
- Material Choice: Stainless steel would have been better for corrosion resistance.
- Process Optimization: Certain steps in the machining process could be refined for efficiency.
The custom thread cleaner, built using the 1500MX CNC mill and other Tormach tools, showcases the versatility of Tormach machines. What will you create with your Tormach machine?
