What kind of tap do I need?

[Pcmaker]

I'm trying to machine something that will thread on to the 3/8 top part of an angle valve. I thought it was 3/8" x 24, but I have that tap size and it's much smaller when I compare it to the angle valve. It's even larger than my 1/2 x 13 tap.

What size do I need? I always thought this was 3/8 x 24 compression as that's what it's called. I need to find this tap and also one that is bottoming.

I measured the major diameter of the thread and it's .558

Could it be that it's something like 9/16 x 24?

 

[Superburban]

This chart shows it as 9/16"-24.

http://www.haywardpipe.com/wp-content/uploads/2015/09/Midland-Compression.pdf

 

[Pcmaker]

Thanks, ordered one from Amazon for $16, should get it tomorrow

We've always called this 3/8 compression, I'm going to guess 3/8 is the ID?

 

[pontiac428]

Yes, compression usually is called out as the I.D. of the tubing used. The thread for the flare nut is going to be larger. Glad you got it sorted without digging out the books of archaic threads to compare to. Plumbing gets funny like that.

 

[darkzero]

3/8" is the tubing size (OD).

 

[matthewsx]

Are you hoping it will seal without the compression gland on a copper pipe? It may work but don't be surprised if it doesn't.

I like PEX for my plumbing jobs.

John

 

[Pcmaker]

I do a lot of plumbing work and sometimes I wish I had something to cap an angle stop that does not fully hold water. I'm going to put a rubber gasket inside the piece I'm making. It's gonna be something like 3 inches long with a knurled handle and a rubber gasket inside the female end to make a water tight connection without needing a crescent or channellocks.

I've been using a brass cap, but with that, I need to put PTFE on the angle valve threads every time. They're so small and hard to work with, too.

 

[matthewsx]

I do a lot of plumbing work and sometimes I wish I had something to cap an angle stop that does not fully hold water. I'm going to put a rubber gasket inside the piece I'm making. It's gonna be something like 3 inches long with a knurled handle and a rubber gasket inside the female end to make a water tight connection without needing a crescent or channellocks.

I've been using a brass cap, but with that, I need to put PTFE on the angle valve threads every time. They're so small and hard to work with, too.

Sounds like you've got it figured out, I was thinking a connector or something like that. You're just trying to keep water from dribbling all over the floor while you're working and don't want to shut the whole house down right? Sounds like the kind of thing you might even be able to sell at the plumbing supply

John

 

[Pcmaker]

Sounds like you've got it figured out, I was thinking a connector or something like that. You're just trying to keep water from dribbling all over the floor while you're working and don't want to shut the whole house down right? Sounds like the kind of thing you might even be able to sell at the plumbing supply

John

Yeah, I work at a hotel/casino and it's a lot harder to shut the water off because the valves are so old not to mention finding them which is what takes the most amount of time, they do not completely shut. I'd have to shut off mains, but they don't want me doing that. I'm talking 6" gate valve mains that havent been exercised in 40 years and we're always in fear of breaking off.

 

[matthewsx]

Yeah, I work at a hotel/casino and it's a lot harder to shut the water off because the valves are so old not to mention finding them which is what takes the most amount of time, they do not completely shut. I'd have to shut off mains, but they don't want me doing that. I'm talking 6" gate valve mains that havent been exercised in 40 years and we're always in fear of breaking off.

Yep, sounds like your shop made tool will be just the thing. I work conferences so usually get to Vegas at least once a year, will send a PM next time and maybe we can get together for a beer.

John