I have been using the small bottles but I have now bought a big one from boc. I put the regulator on (very tightly with a spanner) and turned the knob, but no gas is coming out. I noticed just under where the regulator screws in to the bottle there is a little thing that can be turned with an alum key. Do i need to turn this to release the gas, or is there something else i have done wrong. The reason i don't just try it is i thought that might be where it is opened to be refilled and i did't want to unsrew it on a full cylinder if that was the case for safety reasons.

Thanks in advance

NO DON'T OPEN ANYTHING ON THE BOTTLE OTHER THAN THE TAP



On your regulator you should have another tap that adjusts gas flow...

You will need to open the tap on the bottle, it shouldn't be an allen key though, it should be a square shape.

So, do this :

Wind the reg knob fully anticlockwise
Open the valve on the bottle (square shaped thing, you'll need a special tool or you might have one on your spanner.
slowly turn the reg knob clockwise to release the gas in a controlled manner

If you have any doubts about this, then take the bottle back to where you got it from and ask the person who sold it to you to explain how to use it. Since they didn't explain how to use it, I'm assuming they didn't give you any safety advice. So read the booklet that they (should) have given you.

Kingr

When I first got my kit from BOC the salesman went through the process of fitting the regulator. As Kingr said, this is best demonstrated, as when you read what I'm about to say you'll appreciate that it's easy to get it wrong!

1. Lay out all the bits you'll need ready for the operation. This is the bottle (!), bottle valve key, regulator, spanners (1 for the cylinder head - about 1.25" A/F - and one for the regulator nut).

2. Put on eye protection! This is vital for the next stage.

3. Remove any seals on the top of the bottle, and ensure that there's no junk in the hole. Insert the bottle key, point the bottle away from you, and BRIEFLY crack open the valve A VERY SMALL amount. By briefly I mean "turn it off as soon as you hear the whoosh". By "very small amount" I mean "squeeze the bottle key a tiny amount until the whoosh starts". This will be VERY LOUD. This clears any small particles of dust out of the coupling.

4. Make sure that the base of the regulator is clean, then mount it on the bottle and hand-tighten (to avoid cross-threading). Line up the regulator then tighten firmly with the spanners.

5. Turn on the bottle with the key (there should be no gas flow at this time, as long as the MIG is connected to the regulator correctly). Your bottle gauge should be showing the pressure.

6. Put a little bit of fairy liquid in a cup with a bit of water, and brush this around all the connections. If you see any bubbles then you will have to take it apart and sort it out. REMEMBER TO TURN THE BOTTLE VALVE OFF BEFORE YOU UNDO THE REGULATOR.

If there are no bubbles, you're ready to go.

As I said, get a professional demonstration!

Disclaimer - this is how I was taught. Your personal safety is your own responsibility. Full gas bottles are bl**dy dangerous things to handle when you don't know what you're doing, or are careless.

(but it's easy when you know how!)

Don't let me put you off - it's a simple operation - it just needs to be done right.

Best advice - get your gas supplier to demonstrate. I have no doubt that he will be more than happy to do it.

rgds,

David

[Edited on 25/2/03 by David Jenkins]

Very well put!

Ever thought of doing a builders manual?

Terry

NO!

I used to write user manuals for software - that was bad enough...

David

That square thing is what i thought it was to release the gas. Its not an alum key as you said, but i just called it. The bloke at the depot did't tell me anything but i think i got some safety sheet from boc when i created the account a little while ago. It works fine now tho, thanks for the help.