04-03-2012, 04:58 AM
Join Date: Apr 2010
Location: Newcastle, Australia
Total Cats: 17
Correct drill bit for 3/8 npt sump fitting
During a garage cleanup Ive lost the countersink style drill bit that was leant to me...(hurr durr).
The sump fitting Ive got is a 3/8th NPT.
Im Asutralian and (have a sense of humour guys) here in Oz we use a measuring system that makes sense.
I figured out that 3/8th npt tap has a diametre is like 16.8mm, or about 5/8th which is stupid.
And now Im trying to find the right sized drill bit.
It seems that a 37/64ths countersinking bit is about right, but where do I get one of those from for a decent price. And what a ridiculous size!
Anyways Ive searched and found that most people have 1/2npt return fittings so that information doesnt translate.
R- i have a 3/8th npt fitting and tap for the sump, what drill bit do I use, preferabbly a metric size or an easy to get imperial size.
Last edited by nitrodann; 04-03-2012 at 06:33 AM.