Drilled pan hole is too small I'm an idiot
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I have a 3/8 NPT to -8AN adapter to put in my oil pan. I went to Home depot and bought a drill and tap kit that came with a 3/8 tap which said on the back to use a 5/16" drill bit. Not thinking, I went out, just finished drilling it, and THEN looked at it and said to myself "my my that's a small hole..." sure enough, looks like 3/8 NPT means a 3/8 Inner Diameter
and I just drilled and tapped a 3/8 diameter hole!
Sooo... what is the CORRECT size tap and drill bit size for a 3/8 NPT hole??
Also, where to find such a drill/tap? Because the 3/8 one I got which is way too small for the 3/8 NPT was one of the largest I was able to find - the kit I bought only goes up to 7/16...
Help please...
-Ryan
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Sooo... what is the CORRECT size tap and drill bit size for a 3/8 NPT hole??
Also, where to find such a drill/tap? Because the 3/8 one I got which is way too small for the 3/8 NPT was one of the largest I was able to find - the kit I bought only goes up to 7/16...
Help please...
-Ryan
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Local industrial place says it's supposed to be a 37/64" drill bit and a 3/8-18 pipe thread tap (which is apparently very different in size from my 3/8 bolt thread tap)...
Can anyone verify this? Does that sound right?
edit: posted this before I saw a few more replies. sounds like I've got the rights sizes now. Are you saying I can use either a 37/64 or a 9/16 bit?
-Ryan
Can anyone verify this? Does that sound right?
edit: posted this before I saw a few more replies. sounds like I've got the rights sizes now. Are you saying I can use either a 37/64 or a 9/16 bit?
-Ryan
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