On Wed, 22 Sep 2010 19:15:31 +0100, "Nightjar wrote:

I used to have a piece of thin wide steel strip that I played around
with until it went over the batten, then slid the slate up it into
place.

Yeah, having drawn a cross section of how the slates lay in relation
to each other and the battens it became obvious that shoving the
ripper up and across the gap and onto the batten *before* you put the
replacement slate in (on top of the ripper) should guide it up and
onto the batten. Always assuming there is enough slack in the roof,
this one was only reslated 5 years ago and is still pretty tight.



--
Cheers
Dave.