Help with a secondary regulator gauge please

[kisslikeether]

I recently bought this regulator on eBay and I'd like to fit a pressure gauge to the blanked off thread but I don't know what size it is.


http://www.ebay.co.uk/itm/121375009853? ... 1439.l2649

The hex socket is imperial, so I guessing that the thread will be. It's definitely smaller than 1/4 bsp as I have some spare gauges that I was hoping to use and they are two big. Can anyone offer any advice?

Many thanks in advance...

[jmc]

As you say the pressure gauge would normally fit in the socket that's been blanked off typically 1/8 bsp


Use a gauge that will take max pressure in your CO2 circuit
I use 30psi ones like this

[kisslikeether]

Thanks JMC.

Much appreciated...

[jmc]

You're welcome.
If you want to be sure of size before ordering gauge then take out blank with Allen key and measure diameter of it.

Compare to a BSP chart like one here

I think 1/8 BSP is 0.383" major diameter & 28 threads per inch

[kisslikeether]

Great, thanks.

Is there a trick to getting these out or is it just brute force?

[Jonnyconga]

They can be really stiff. I think something like plumb weld(?) Is used on them sometimes. Get an Allen key that fits perfectly and use a mole grip or similar to extend the leverage. I've also clamped the key in a vice and twisted the reg.
make sure you use PTFE tape when putting the new one in.

[kisslikeether]

Thanks for the advice. I managed to get the blank out this afternoon with an Allen key and grips. I also managed to recycle an old gauge which seems fine. I used plenty of PTFE tape. Assuming the cylinder isn't empty tomorrow I'll be feeling rather chuffed.