Re: Low-cost retail CO2 bottles?

In article <siegman-0B1171.08131228072005@xxxxxxxxxxxxxxxxx>, AES <siegman@xxxxxxxxxxxx> writes 
A bit OT, but would any of the amateur laser makers on this group know
the best (cheapest) way to purchase retail CO2 bottles, with slow-flow
regulators, for home use?

(Not for CO2 lasers, actually -- one of the ways to fight an infestation
of moles and ground squirrels in a lawn is allegedly to direct a slow
flow of CO2 into the tunnel system.  So, what's the easiest way to
purchase low-cost, low-purity, low-hassle CO2 in small amounts?
Already tried dry ice -- works, but expensive, and can't store it for
long periods.  Fire extinguisher refills also seem to be expensive.)

(1) Pubs (you probably call them bars!) use CO2 cylinders to pressure draught beer out of kegs - at least they do here.

(2) You can probably find a local supplier of bottled gases who would be prepared to supply. The cost of renting the cylinder will almost certainly exceed the cost of the gas.

(3) Buy a Kipps generator (they come up on eBay) and use it with marble chips (CaCO3) and dilute sulphuric or hydrochloric acid*. The way these work (Google it) would allow you to produce slow or intermittent controlled amounts as needed.

(4) Gather a large bunch of newsgroup contributors and ask them to breath down the hole.

*PLEASE don't use concentrated acids, or even buy them to dilute, unless you know what you are doing.

David
--
David Littlewood
.