Small generator

[geoff]

... Drinking their pina coladas through a straw at the bar

[Matt A]

:rofl:

[Ian White]

Just testing... yes, a light came on :-)

[tony sayer]

In article , Angela scribeth thus

Right missed that!. Was in Hospital at that time!..

[Dave Liquorice]

This is true but a length of pipe and a good suck and you wouldn't have to drive any where. B-) Petrol tastes foul though and you'll taste it for a day afterwards. Much better to get a little "fuel transfer" hand pump...

As with all backup proceedures make sure you have all the require elements to gether and test them before you need to use them in anger. It might not be possible to syphon petrol from your car.

[Graeme]

What you need is a length of hose, a slightly longer length of wire and a tampon. Connect the string of the tampon to the wire, thread wire through pipe, dip pipe into fuel tank and pull the wire/tampon. The tampon expands, and causes a vacuum as it travels back through the pipe, and Bobs your proverbial. No sucking, no foul taste, minimal expense.

[John Rumm]

And again, because I just rewrote it! ;-)

[NT]

Or you could heat the water directly. Monitor the electric heater so you find out its duty cycle, multiply that by the 300w then you know how much non-thermosttic power you need to keep the tank warm.

There are assorted possible ways to do it, a couple of perhapses:

1. Create a simple miniature metal boat. Give it a roof which connects to the hull and place a tealight or 2 inside. Only usable for tiny fish that can't upset it.

1. Add a (copper free) sconce inside the tank just above the water line, plus a piece of sheet ali that goes down into the water and curves over the top of the candle.

2. Place a paraffin burner or row of candles beneath the tank - essential they're spaced a fair distance away so they just give warmth all over, no hot spots.

If you wanted to get creative you could build a miniature sterling or steam engine so the heat also provides air pumping.

If done competently such kit could prove hugely more reliable and long lived than a genny, and silent.

NT

[Mike Harrison]

Wonder how long a tank of compressed air would last as a backup....

[geoff]

In message , Graeme writes

But you can only do that once a month

[geoff]

I have a couple of fish which would give our cat a run for its money

maybe not ...

Just underneath the polystyrene ?

now there's a plan

Hamster wheel and a resistor

[geoff]

Prolly until it was empty ...

seriously, you would have to be careful that there was no contamination such as compressor oil

[NT]

I'm not clear how thats relevant to a floating heater in the tank.

erm.... no

[Pete Verdon]

I assumed Mike was talking about a diving cylinder. That's a pretty good thought - even with the valve full open roaring out air so fast that it's covered in ice, they take a while to empty. A 12 litre cylinder at

230 bar has 2760 "litres" of surface-pressure air in it. I've no idea what flow rate fish tanks need, but with a total finger-in-the-air figure of 2 litres per minute that's nearly 24 hours of electricity-free bubbling.

Obviously a diving cylinder will be free of oil etc - the concentration of such things increases with depth so they need to be *really* clean to start with.

Pete

[Mike Harrison]

..and if you ask nicely you may be able to get an occasional refill at your local fire station.

[Dave Liquorice]

Sounds like the voice of experience. Is it?

I think the tampon would have to be in the hose when dipped I don't think you could pull it into the hose once expanded.

[Dave Liquorice]

The little 650W 2 strokes are pretty light, the Honda EU10i is only

13kg (dry) fueled and oiled I doubt it tips 15kg. The open frame jobbies are somewhat heavier. The EU20i can be picked up with one hand and moved like a heavy suitcase, that's 21kg dry.

When the power goes most mobile coverage goes with it. The good old wired analogue telephone will stay working, even tiny remote exchanges have batteries and gen sets to keep them working.

[Pete Verdon]

Interesting. Do firefighting cylinders run at the same pressures? Since they only ever need to supply at 1 bar it seems to me that they could usefully have lower-pressure cylinders for a lighter weight (obviously handy when running around a burning building) and still get a worthwhile run time out of them.

Back when I used to dive the going rate for a fill was about £2, and there's a garage I drive past every day with a sign outside offering diving air, so it shouldn't be an issue really. TBH my main concern at using them for an emergency fish-bubbler would be keeping (or not) the bottles in test. If they're just kept for an emergency I probably wouldn't worry about it until needing to fill up again.

Pete

[dennis]

Does hydrocarbon fluid make them expand at all?

You don't need anything other than the pipe. You need to expel the fumes from the pipe by blowing before you suck, its just a matter of putting your thumb over the end to stop you getting a mouthful of liquid.

[Mike Harrison]

Firefighting BA cylinders use either 200 or 300 bar (depending on country/brigade). Unlike divers they need to be able to support high-usage activity like climbing stairs etc. whilst guaranteeing sufficient reserve for man-down situations & blocked escape routes. They also like the cyls to be physically small for manouverability - don't know how they compare with dive tanks size-wise.

On the subject of weight, the company I did some BA instrumentation work for a while ago developed a very nice carbon-fibre wrapped aluminium triple-sphere system which was super-light and a much more ergonomic shape, but failed in the market as it is a very conservative business where new ideas are hard to sell. I think the Yanks also didn't like the idea of what would happen if one got shot....