Sterling Gun Drills Media Releases
Gun Drilling on a CNC or Manual Lathe or Mill
For hole depths greater than 40 diameters deep, we suggest a shorter drill / longer drill combination that will allow the drilled hole of the shorter drill support the flute of the longer drill.
On a lathe or milling machine, a gun drill bushing to start a single flute gun drill is generally not practical. Drill supports, chip box, etc., are also unnecessary.
Start a gun drill with a pilot hole drilled, reamed, or bored to the gun drill diameter +.0005" (+.001" max.), -0 x ½ to 1 diameter deep. The shape at the bottom of a pilot hole is of no consequence.
Use oil, or oil based, high "EP" water soluble coolant at 10-12% concentration, NEVER use a synthetic as these have no lubricating action. General guidelines:
We offer our DM2000 / DM3000 Spraymist Kits as alternative to high pressure coolant. Operate with 100-125 psi of shop air pressure. Spindle speed will be same as Min psi above. Refer to our Speed & Feeds chart or our helpful Gundrilling Guidelines.Drilling:
- Enter the drill tip into the pilot hole dead spindle just off the bottom.
- Start the oil, coolant or our Spraymist System.
- Start the spindle.
- Drilling will be continuous to depth.
- When to depth, back off the bottom slightly if a blind hole, stop everything and remove the drill.
- NEVER rotate the drill outside of the hole.
Special nose grind / Contour combinations are available for very deep holes, cross holes, interrupted cuts, special shapes, steps.
Doug Holley, General Manager
Sterling Gun Drills, Inc. North Bennington, VT.
Toll Free: (888) 338-1049 • Phone: (802) 442-3525 • Fax: (802) 442-6225
Company Website: www.SterlingGunDrills.com