An application that requires compressed gas - a CO2 fire extinguisher is
known to be a suitable source.

Does anyone know how I can obtain a couple of fire extinguishers that have
been taken out of service (but are more or less full)?

Obviously scrap prices would be preferable.

TIA.

On Jan 30, 4:37*pm, "ian field"
wrote:
An application that requires compressed gas - a CO2 fire extinguisher is
known to be a suitable source.

Does anyone know how I can obtain a couple of fire extinguishers that have
been taken out of service (but are more or less full)?

Obviously scrap prices would be preferable.

TIA.

You *might* be able to get some from an extinguisher servicing
company, but for liability reasons they might not let old ones out the
door.

Maybe you could watch auctions for when a building/business closes?

Would soda cylinders work as well?


Dave

wrote in message
...
On Jan 30, 4:37 pm, "ian field"
wrote:
An application that requires compressed gas - a CO2 fire extinguisher is
known to be a suitable source.

Does anyone know how I can obtain a couple of fire extinguishers that have
been taken out of service (but are more or less full)?

Obviously scrap prices would be preferable.

TIA.

You *might* be able to get some from an extinguisher servicing
company, but for liability reasons they might not let old ones out the
door.

Maybe you could watch auctions for when a building/business closes?

Would soda cylinders work as well?


Dave

Its for blowing tubeless tyres onto their rims - using a fire extinguisher
the right way up pumps liquid CO2 into the tyre, resulting in alarming
creaking and pinging noises, using the fire extinguisher upside down only
lets evaporated gas into the tyre and works perfectly.

I have a tubeless repair kit with "mushroom patches" and insertion tool,
these come complete with a soda siphon style CO2 bottle - the instructions
state clearly this is not adequate to reseat dislodged tyre beads.

"ian field" wrote: Would soda cylinders work as well?
^^^^^^^^^^^^^^^^^^^^
CO2 is used in MIG welding also.

On Fri, 30 Jan 2009 15:47:14 -0800, "Leo Lichtman"
wrote:


"ian field" wrote: Would soda cylinders work as well?
^^^^^^^^^^^^^^^^^^^^
CO2 is used in MIG welding also.



And in bars that sell American fizzy beer.


Mark Rand
RTFM

On Fri, 30 Jan 2009 22:13:30 -0000, "ian field"
wrote:
wrote in message
...
On Jan 30, 4:37 pm, "ian field"
wrote:

An application that requires compressed gas - a CO2 fire extinguisher is
known to be a suitable source.

Does anyone know how I can obtain a couple of fire extinguishers that have
been taken out of service (but are more or less full)?

Obviously scrap prices would be preferable.

You *might* be able to get some from an extinguisher servicing
company, but for liability reasons they might not let old ones out the
door.

They will NOT let them out the door as-is, I've tried. The usual
reasons they get scrapped as fire extinguishers is that the
instructions band with the maker name and model numbers is damaged and
unreadable, or the horn and hose or head/handle are unserviceable and
no spares are available, or the seals in the head have died and the
company is gone so they are no longer available. (Sounds stupid, but
to be rated they have to buy the O-rings from the original maker.)

I have a local FE shop that will gladly do the needed Hydrotest,
install a standard CGA200 (?) valve (without the syphon) and refill
it. Then you can use it for american-style beer or soda, or as
welding shielding gas, or to blow out HVAC drain lines.

Maybe you could watch auctions for when a building/business closes?

Would soda cylinders work as well?

Its for blowing tubeless tyres onto their rims - using a fire extinguisher
the right way up pumps liquid CO2 into the tyre, resulting in alarming
creaking and pinging noises, using the fire extinguisher upside down only
lets evaporated gas into the tyre and works perfectly.

I have a tubeless repair kit with "mushroom patches" and insertion tool,
these come complete with a soda siphon style CO2 bottle - the instructions
state clearly this is not adequate to reseat dislodged tyre beads.

You do NOT want to use liquid CO2 for this! Not good to freeze the
rubber by injecting Liquid CO2 that is going to flash into Dry Ice
inside the tire, chilling it to way below zero (C or F) - and then
expect the tire to flex easily into position... Not to mention that
when the Dry Ice evaporates into gaseous CO2 you could overinflate the
tire to the bursting point REALLY easily - long before you could vent
it out the valve stem.

Build a copy of the "Cheetah" bead blast bottle instead, uses
compressed air. (Could use gaseous CO2 to fill the tank too, but
that's a technicality - many non-flammable compressed gases would work
if you don't have an air compressor handy.)

You can fabricate one using an old 5 gallon/20 Lb/10KG LPG bottle
and a ball valve and a piece of pipe flattened into the oval blast
fitting (with a little hook/tab on the end to hold in position on the
rim flange) - but you need a certified welder to install a large bore
pipe flange on the bottle. You need a 2" (~ 50MM) pipe and ball valve
to move a lot of air out of the bottle in a hurry.

You basically aim the blast output tube at the gap between the tire
and rim and slam open the valve, and try to play the tire like a flute
- the air blast goes inside and bounces, then the bead is blown up
onto the rim when the air bounces back. Noisy, but it is safe and
works like a charm.

-- Bruce --

"Bruce L. Bergman" wrote in message
...
On Fri, 30 Jan 2009 22:13:30 -0000, "ian field"
wrote:
wrote in message
...
On Jan 30, 4:37 pm, "ian field"
wrote:

An application that requires compressed gas - a CO2 fire extinguisher
is
known to be a suitable source.

Does anyone know how I can obtain a couple of fire extinguishers that
have
been taken out of service (but are more or less full)?

Obviously scrap prices would be preferable.

You *might* be able to get some from an extinguisher servicing
company, but for liability reasons they might not let old ones out the
door.

They will NOT let them out the door as-is, I've tried. The usual
reasons they get scrapped as fire extinguishers is that the
instructions band with the maker name and model numbers is damaged and
unreadable, or the horn and hose or head/handle are unserviceable and
no spares are available, or the seals in the head have died and the
company is gone so they are no longer available. (Sounds stupid, but
to be rated they have to buy the O-rings from the original maker.)

I have a local FE shop that will gladly do the needed Hydrotest,
install a standard CGA200 (?) valve (without the syphon) and refill
it. Then you can use it for american-style beer or soda, or as
welding shielding gas, or to blow out HVAC drain lines.

Maybe you could watch auctions for when a building/business closes?

Would soda cylinders work as well?

Its for blowing tubeless tyres onto their rims - using a fire extinguisher
the right way up pumps liquid CO2 into the tyre, resulting in alarming
creaking and pinging noises, using the fire extinguisher upside down only
lets evaporated gas into the tyre and works perfectly.

I have a tubeless repair kit with "mushroom patches" and insertion tool,
these come complete with a soda siphon style CO2 bottle - the instructions
state clearly this is not adequate to reseat dislodged tyre beads.

You do NOT want to use liquid CO2 for this! Not good to freeze the
rubber by injecting Liquid CO2 that is going to flash into Dry Ice
inside the tire, chilling it to way below zero (C or F) - and then
expect the tire to flex easily into position... Not to mention that
when the Dry Ice evaporates into gaseous CO2 you could overinflate the
tire to the bursting point REALLY easily - long before you could vent
it out the valve stem.


Its quite obvious you didn't bother to read what I said about using the
extinguisher upside down.

On Sat, 31 Jan 2009 16:05:37 -0000, "ian field"
wrote:


Its quite obvious you didn't bother to read what I said about using the
extinguisher upside down.

Yes, I did. You do NOT use the fire extinguisher squeeze valve to
inflate tires either way (cylinder upright or inverted) - using
unregulated cylinder gas that can be 200 to 400 PSI into a tire that
will burst at 50 to 100 PSI (depending on size and construction) could
be suicidal.

And using a liquified gas like carbon dioxide is far worse, because
you can get a larger volume into the tire faster. Then it expands
exponentially in volume when it converts from a liquid into a gas, and
that volume expands even more as it warms from a cryogenic gas to room
temperature.

You have a service shop convert the fire extinguisher lever valve to
a standard CGA 200 handwheel globe valve /without/ a siphon, and then
use a regulator to control the gas output pressure.

And when using a Cheetah bead seating blast tank, you control the
tank pressure so the tire is not overinflated when the bead does seat.
The only safe way I can see to use liquid CO2 for bead seating would
be a metering system - you trans-fill a calibrated chamber or charging
cylinder with the liquid gas, so the shot injected isn't too much for
the tire volume.

-- Bruce --

"Bruce L. Bergman" wrote in message
...
On Sat, 31 Jan 2009 16:05:37 -0000, "ian field"
wrote:


Its quite obvious you didn't bother to read what I said about using the
extinguisher upside down.

Yes, I did. You do NOT use the fire extinguisher squeeze valve to
inflate tires either way (cylinder upright or inverted) - using
unregulated cylinder gas that can be 200 to 400 PSI into a tire that
will burst at 50 to 100 PSI (depending on size and construction) could
be suicidal.


Its a motorcycle tyre which uses higher pressure than a typical car tyre.

The first time I did this I made the mistake of using the extinguisher right
way up - it made alarming creaking noises but nothing worse than that.
needless to say a disaster was avoided by remembering to leave out the valve
core.

The second tyre I remembered to invert the extinguisher and a couple of
quick jabs on the lever did the job absolutely perfectly.

If you're a tyre fitter that makes a very cosy living ripping off Joe
public - then hard cheese.

ian field writes:

Does anyone know how I can obtain a couple of fire extinguishers that
have been taken out of service (but are more or less full)?

I have gotten them at plant closings for $1/each when they were expired on
the fire-safety annual inspection! For a while they were really out of
fashion and easy to find like that.

CO2 fire extinguishers are just standard gas cylinders (20 lb size typical)
with a siphon tube valve and horn. They can be easily switched to ordinary
CGA 320 valves by any welding gas supplier who does the ordinary hydro
testing, or vice versa. If your application doesn't need genuine
extinguisher approval (maybe you're doing movie special effects, say) then
this should be easy for any gas supplier to service at about $25/fill for a
20 lb size:

http://www.truetex.com/carbonation.htm

"Richard J Kinch" wrote in message
. ..
ian field writes:

Does anyone know how I can obtain a couple of fire extinguishers that
have been taken out of service (but are more or less full)?

I have gotten them at plant closings for $1/each when they were expired on
the fire-safety annual inspection! For a while they were really out of
fashion and easy to find like that.

CO2 fire extinguishers are just standard gas cylinders (20 lb size
typical)
with a siphon tube valve and horn. They can be easily switched to
ordinary
CGA 320 valves by any welding gas supplier who does the ordinary hydro
testing, or vice versa. If your application doesn't need genuine
extinguisher approval (maybe you're doing movie special effects, say) then
this should be easy for any gas supplier to service at about $25/fill for
a
20 lb size:


Its for seating tubeless tyres, the fire extinguisher lever works perfectly
as a quick jab works perfectly to seat the rims - I imagine that changing to
a rotary valve would make the operation much more dangerous.

If I could find someone to refill the fire extinguisher I have, and remove
the siphon tube while they're at it, it would be marginally more convenient
in not having to invert it (I've already found out what happens when you
pump liquid CO2 into a tyre!).