On Fri, 28 Aug 2009 07:26:00 +0100, "Calvin Sambrook"
wrote:

One inherent problem however is that this type of diverter is a constriction
in the downpipe which means that stuff, like typically a blob of moss, can
be small enough to enter the top of the pipe but big enough to not get past
the fitting.

This is where a larger pipe is better as it is less likely to become
blocked?

I guess the ribbed, flexible pipes are most prone to becoming blocked
because they are not smooth?

I collect a good few cms each year which need to be cleaned out

How do you do that? Do you have to climb into the butt with a trowel?

concrete tiles which spall, so much of it is fine sandy sediment

Ah, so that's where it comes from!

The butt described above is fed from a diverter which I'd love to be able to
buy but which seems no longer to be sold. It is a Y-shaped fitting, sort of
a straight downpipe with another pipe sticking out at about 45 degrees and
pointing downwards IYSWIM. It fits into the side of the butt near the top.
Inside the fitting there is a fixed flat plate in the center line of the 45
degree pipe such that water coming down the pipe is forced out of the exit
pipe and into the butt, when the butt is full water spills under the plate
and down the downpipe into the ground. Obviously it collects every last
drop of water.
Anyone know if they are available anywhere? (The backup plan is to make one
from fittings when I get time).

The picture is not brilliant but is it something like this? It doesn't
have the branch at 45 degrees (or should that be 135 degrees?) but it
does have a 45 degree plate inside.

http://www.combinedharvesters.co.uk/...ory=10#details

Expensive though.