Outdoors, away from any flame, remove the fill valve in the centre of the threaded stem. Most will unscrew like a car tire valve core. This will vent any pressure inside the bottle. If it does not unscrew, depress the valve stem to vent all remaining pressure, then drill the valve out while running water around the twist drill. Leave outside to vent for a day or two. Fill with water, place in jaws of workmate, Drill a 3/8 dia hole midway up the bottle. Using a hacksaw blade in a handheld jigsaw, or a portable bandsaw, cut the bottle in two midway up the bottle. You now have two harmless pieces of steel scrap that can not be pressurized or cause explosion or fire. You can divide the pieces further of course if you want. I usually leave the pieces outdoors for a few more days to allow any odorant from the gas or entrained gas in or on the metal to dissipate.

Note that you need to be aware of all local laws about such practices, and not do it at all if it is prohibited where you are.

Edited By Jeff Dayman on 07/05/2021 14:36:11

Or what I use, for 1.52 UK pounds at Amazoon:

I would be surprised if several of your car-owning friends or relatives don't already have one though.

Is that gas mixture – see Screwfix website – hotter than the ordinary Calor propane?

I believe propane is propane, so no. The torch that the gas bottle fits uses air at atmospheric pressure. If you want more hotness using propane as the fuel gas, I think you can use compressed air (like the Flamefast brazing hearths) or oxy-propane.

The same style of gas canister is available in a yellow colour and contains MAPP gas (also called MAP, MAP-X or MAP plus). Burning in air, this does produce a hotter flame.

DC31K:

Thank you.

I gather from Wiki that the MAPP story is a bit complicated.

Why does anyone not just use up all the gas for the purpose for which it is intended? You got money to burn?

Re using up all the gas – I always use these small cylinders until the torch won't run anymore, but there is always a wisp or two of gas in them afterward. Very little, but some. Can't see a way around it except to maybe refill the cylinder. I am aware this is technically easy to do – in fact I have been present when it was done – but locally it is against the law to do it. Not sure why. There may be a concern by authorities that the small cylinders could be over pressurized if fed from the wrong kind if gas supply, maybe? or maybe big merchants lobbied the regs so they can keep selling bags of these small tanks to people……

Re giving these small cylinders to the local waste/ dump staff – local to me, the waste station / dump will not accept gas cylinders of any kind. No problem with scrap steel though, as mentioned in my first post above.

I don't know what other local authorities do but my local Tip does accept disposable gas cylinders – I just hand them to the Man. Did it two weeks ago.

Re-fillable cylinders are a different thing – I believe they are owned by the 'gas' company – but since they can be exchanged for refills – I'd just stick any unwanted spare bottles on Gumtree.

Regards,

IanT

I've been making these candlesticks for clients out of their horses old shoes .. they love them ! The cups are bits of exhaust pipe capped off with a disc of steel ,cheapskate me .. I thought of using core plugs, until i saw the price of them..

My daughters old pony died last month , and she asked me to make her one from his old shoes , but for only one candle.. The bottom of a disposable mig gas bottle came in handy !

( They won't take them at the recycle tip despite there being a recycle symbol on the cylinder ..)

There must be millions of these disposable bottles worldwide that get thrown in the garbage or recycle bins but we never seem to hear reports of explosions etc. I suppose theoretically if the cylinder is full of gas but no air it can't explode? I would think they get sorted out at the garbage dump when recyclables are separated in most places. Otherwise buried in landfill so no great hazard. There is plenty of explosive methane gas coming out of those places anyway.

As far as drilling, cutting and welding etc of old gas bottles, it makes me a little nervous. I would never do that to a petrol tank or petrol tin without steam cleaning it first and filling with inert gas such as CO2 or argon. They do explode fairly regularly when being welded by careless bush mechanics and the like. Not sure how gas compares when it comes to lurking in seams and pores in the metal and lying in wait for the unsuspecting?

Edited By Hopper on 08/05/2021 01:02:52