On 2014-06-01 11:29:24 +0000, Sacha said:

On 2014-06-01 09:27:20 +0000, T Blake said:

We want to make a Cloche with hoops of bent-over plastic water pipe,
covered in Plastic sheeting; to end up like a minature Polytunnel for
the allotment.

We dont know where to get a large sheet of plastic from here in North
West London, so we are going to stick together 'cut-open' clear plastic
bags.

What would be the simplest way to stick the bags together, and if glue
is the answer; what is the best type of glue to use please? Bearing in
mind we would probably have to use lots of it and it would have to be
one hundred percent waterproof. Thanks.

Try looking here and on eBay. http://www.gumtree.com/for-sale/uk/polytunnel

Plastic bags won't last 5 minutes.

If you can afford to buy one of the tunnels advertised, it could save
you hours of work and frustration which all comes to nothing. It will
certainly extend the range of plants you can grow and the length of
time it takes to grow them. But one major enemy of polytunnels is wind.
You need to have a sturdy frame for them and the edges of the plastic
sheeting need to be well buried in the soil either side to hold them
down. Here, trenches are dug either side of the tunnel for the
'overhang' to be buried in. And choose a totally windless day to
construct the thing, or you and the poly sheet could end up in the next
county! It might be worth your while looking on sites of nurseries
selling off stock as they - unfortunately - go out of business and/or
the owners retire.
--

Sacha
www.hillhousenursery.com
South Devon
www.helpforheroes.org.uk