Finding the Right Product for Deep Hole Drilling

There are a few options when drilling to a depth ten times the diameter. Gun-drilling, trepanning, HSS peck feed drilling, solid carbide twist drills, spade drills and coolant fed carbide twist drills in a variety of lengths can all be used depending on the drilling machinery available and the quality and volume of parts that are going to be produced.

If the diameter of the hole required is between 1/8” and about ¾” consider coolant feeding solid carbide twist drills. These are not as costly as gun drills or trepanning tools and are more reliable than peck feeding high speed drills or assembled spade drills. Readily available in fractional and metric sizes, these drills are designed for single pass drilling in everything from cast and malleable iron to alloy steels and stainless steel.

Coated coolant fed drills can be run three times faster than comparable high speed or cobalt  tools and generally at least half the feed rate. This means considerably increased production. Royal HP drills from Regal Cutting Tools are designed with 140 degree split point for easy starting, flute shape and helix angles to maintain straightness at extreme depths and cutting faces to produce high quality surface finish.

Most machining centers and specialized drilling equipment are equipped with reservoirs and pumping mechanisms to produce the pressure and volume needed for good drilling performance. As a reference a ¼” drill should have about a half a gallon per minute at 200 PSI and a ¾” drill two and a half gallons per minute at 75 to 100 PSI. For older model machining centers there are retrofit Systems with coolant through the tool holder available. However, the machine system must be capable of producing the volume and pressure necessary.

Royal HP carbide coolant feeding drills are available is short long and extra-long lengths in sizes from 1/8” or 3 millimeters to 5/8” or 20 millimeters. Contact us to select the right tool for your requirements.