In message , Brian-Gaff
writes
Sandpits can be a real pain to keep animals out of of course, but one has to
be sure the device for covering them is not itself dangerous.

I'm thinking of a light steel frame covered in waterproof woven plastic
sheet.

as for making the right constituancy, there was, believe it or not a study
done about the correct types of sand and mixture of water, to make good
sandcastles as it was needed for a comercial project i seem to recall. the
type of sand is very important.

Play pit sand is claimed to be *rounded* rather than *sharp* for safety
reasons and also much finer than sea sand. The appearance is similar to
moulding sand used in metal casting.

I tried whacking the moulds with a metal trowel but still failed to get
a clean release.

I just wish I could remember what I was looking for when i found it by
accident.

Oh well. Another of life's imponderables:-)
--
Tim Lamb