On 25/04/2013 13:09, The Natural Philosopher wrote:
On 25/04/13 12:39, Gazz wrote:


"Tim+" wrote in message
...
wrote:
On Thursday, April 25, 2013 10:19:43 AM UTC+1, Tim+ wrote:
I'd like to experiment with using a 2L coke bottle as a pressure
vessel but I haven't worked out how best to make a leakproof plumbed
connection to the bottle.


http://www.mindsetsonline.co.uk/prod...roducts_id=354


Nice, but I think the connections would be just too small. I want it
to act as a pressure reservoir to prevent rapid pump cycling in a
motorhome pumped water system. The exisiting system uses a pressure
switch which was okay with the old pump but a new uprated pump is
causing problems and the recommended solution it to fit a pressure
accumulator

Of course I could just spend lots of dosh and buy the recommended one
but it's more fun to try and do it on the cheap. ;-)

http://www.ebay.co.uk/itm/SHURFLO-Ac...item27d2223cd7


Firstly, a 2 litre pop bottle is pretty flimsy, whilst it will handle
the couple of bar pressure in a motorhomes water system, can it handle
the vibrations and movement from driving down the road... basically if
it fails, you will pump the contents of the water tank into the living
area,

well fizzy drinks bottles already take similar pressures and have screw
on caps.

Hardly rocket science to drill through the cap and mount up a gas tight
fitment to one.

Indeed - one bottle with a hole drilled through the cap and a car tyre
valve pulled into it, full of compressed air; connected by a double
ended car pump hose to another bottle with a valve in the base, full of
water and a hose connected to the cap end; with a valve on the end of
the hose makes a very good water pistol, with excellent range and
continuous flow.

Not that I'm admitting to taking such devices to Run To The Sun many
moons ago!

SteveW