In this video, The Sensor Connection walks you through the correct way to drill and tap a 1/8-inch NPT hole for installing EGT probes, pressure transducers, and other threaded sensors.
We cover everything you need to know to achieve a clean, reliable, and leak-proof fit — including drill size selection, surface prep, pilot drilling, tapping technique, and proper thread depth.
What you’ll learn:
• Why NPT tapered threads create a reliable seal
• The correct drill size for 1/8" NPT (Q bit / 0.332")
• How to prep your drilling surface for accuracy
• Why pilot holes prevent tool wandering
• Tapping technique: lubrication, forward/back turns, and avoiding oversizing
• How to test-fit your sensor for a perfect seal
With the right technique, you can create professional-quality NPT ports that stand up to heat, pressure, and vibration in demanding automotive and industrial applications.
CONTACT US now for additional technical assistance and pricing questions.