On Fri, 11 Sep 2009 13:25:02 +0100, Stephen wrote:

I thought 15mm plumbing might be too slow because I had read threads
here about the flow from the tap being so poor.

Thats down to the restriction at the valve. If you are worried get a
full bore 1/4 turn lever valve.

15mm bib taps. (What is a bib BTW?)

Thing babies/toddlers wear around their necks when being fed or
feeding themselves to protect their clothes from food that misses the
mouth.

In the context of a tap, donno...

Is there a way to reinforce the butt. Since it would be submerged, I
guess it would have to be brass. Could a brass plate be put inside
behind the tap? Where could you buy a suitable square of brass from?

Remember that this plate may well have to be curved to fit the round
side of the butt and maybe in the other direction as well. ie be part
of spheroid shape. If the threaded part sticking into the tank is
long enough you might be able to fix/seal that then have another nut
to hold the plate in place. But bear in mind you are probably going
to be fitting it 4' down an 18" dia tube, not the easiest of places
to reach, particularly as you may need to be at both sides at the
same time...

--
Cheers
Dave.