Pro/Forums - View Single Post - Copper tubing -- all opinions wanted

grep · 01-02-2002, 09:37 PM

I was surprised to find that a 1/2" threaded hose barb using 1/2-14 npt threads requires a 27/32 drill bit and after its tapped its max diameter is .84375, if you go up 1/32 in drill size you use a 7/8ths drill bit and thats exactly the size of 3/4" copper tubing.
I think almost any block should be able to take a 1/32 increase in hole size especially since it doesn't need to be tapped.

I did a little research and a 1/2" threaded hose barb with a 1/2-14 NPT x 1/2 hose would have an od of .84375 and an id of .611 and a 3/4 schedule M copper tube would have an od of .875 and an id of .811. Thats a hell of an increase.

Grep

01-02-2002, 09:37 PM	#23
grep Cooling Neophyte Join Date: Mar 2001 Posts: 37	I was surprised to find that a 1/2" threaded hose barb using 1/2-14 npt threads requires a 27/32 drill bit and after its tapped its max diameter is .84375, if you go up 1/32 in drill size you use a 7/8ths drill bit and thats exactly the size of 3/4" copper tubing. I think almost any block should be able to take a 1/32 increase in hole size especially since it doesn't need to be tapped. I did a little research and a 1/2" threaded hose barb with a 1/2-14 NPT x 1/2 hose would have an od of .84375 and an id of .611 and a 3/4 schedule M copper tube would have an od of .875 and an id of .811. Thats a hell of an increase. Grep __________________ every thing is optional