I have to admit, I'm not very good at draining my compressor after I've used it, which is bad, and I guess in the long run, dangerous.

Its in a very awkward place, not easy to turn, and not easy to tighten and seal after its drained. I'm looking at trying a modification to make it easier

What size thread is the drain screw likely to be? I guess they're generally standard? Its a clarke 150l one.
I thought 1/4" npt, but when I look for bits, they're in america, and the ones here are 1/4" bsp?

In the small sizes BSP and NPT are so close as to make no practical difference.

Cheers

Fred W B

I think you'll find the fitting in the tank which the drain screw assembly fits into is 1/4" BSP, the thread will be about 1/2 dia but tapered.

[Edited on 19/2/13 by r1_pete]

My compressor had a 1/8"bsp drain cock that was a fiddly critter to get at. I extended it with copper pipe and put a 1/4 turn valve that pointed to a srain just outside my garage door.

Hmm, machine mart seem to sell 3/8" drain taps, a 3/8" to 1/4 reducer, and then nothing else of any useful size that fits either
www.machinemart.co.uk/shop/range/guid/E05B1C89-438D-4C1A-869F-253E794EAA6E?da=1&TC=SRC-drain+tap

The plan is to stick a ball valve on it somehow. I guess I'll have to go in the shop next time I'm there to get bits I need

240v timer relay and 240v solenoid valve if you want to get really clever

I didn't even know you had to drain them!

Ha ha Nat, im not made of money! And doesnt have power to it unless im using it. Though a 240v solenoid valve and a switch on a spur from the 32a plug...
Keep it simple! Ha ha, guess I'll have to get the tap out and take it to machine mart or something for the right size

Yep joel, get it drained! Bottom of the tank, open the valve. Get a video of how much comes out :O

In humid conditions our workshop one generates a couple of litres a day, and the blasting compressor, well, in a 6 hour session there's a LOT of water from the two separators, but that is 50hp 130cfm!

mines only on when i use it, which isn't much. when i open the tap, the most i've had is a few ml really, but i don't drain it as often as i should...

a few elbow pipes and a ball valve will do the trick i think

Have you thought of using nylon?

A 1/4" bsp swivel elbow. (with reducing bush if you have a larger drain plug)
Length of nylon tube. (6mm dia would be plenty)
Straight connector. (6mm to 1/4 bsp)
1/4" ball valve

As your drain is awkward to get to you would end up with a remote drain point.

My air lines that run around my workshop roof are all push fit nylon.


Cheers,
Paul G