Cost-Comparison

Shops often ask me whether they should use a CNC lathe for gun drilling or buy a dedicated machine. The answer depends on the volume, the hole requirements, and the depth-to-diameter ratio. I’ve used both approaches on hundreds of jobs, and each has its place. When a CNC Lathe Works A CNC lathe with live tooling and through-coolant capability can handle shallow gun drilling work up to about 10:1 L/D ratio. The main limitations are coolant pressure — typically 300-500 psi — and the lack of a guide bushing support for the drill entry. ...

Choosing between a dedicated deep hole drilling machine and using a standard CNC machine depends on the volume and depth requirements. I have worked with both configurations across multiple shops and the answer is rarely a simple one-size-fits-all. Over the years I have developed a framework for making this decision based on production volume, depth-to-diameter ratio, and tolerance requirements. Cost Breakdown: Dedicated vs Standard Machine A dedicated deep hole drilling machine costs $150,000 to $400,000 new, but the purchase price is only the beginning. When I put together a full cost comparison for a shop considering this investment, I look at several categories beyond the machine itself. ...