What size drill bit do I need for 1/4-20 helicoil?
What size drill bit do I need for 1/4-20 helicoil? Sitemap UNC Insert Size Drill Size Wire Thread Insert Length 12-24 5.8 mm 0.216 1/4-20 6.7 mm 0.250 5/16-18 8.3 mm 0.312 How do I know what size helicoil drill I need? F is equal to the insert nominal length Read more…