Whats the difference between Marine and Exterior Ply?
Chris
need to make up an advertising sign which hopefully
will last a few years in an exposed site.
Any suggestions for sealing the edges as they are obviously
prone to water ingress and rot. The last one succumbed to this
after 3 years. It had a baton frame but I think this made it
worse as water seeped into the gaps.
Many thanks
Chris
Peter D Jones
Exterior: must use a synthetic resin glue and inherently durable timber.
Glue types vary and so therefore does the price. "Proper" exterior ply will
use a WBP (water and boil proof) glue. Some others called exterior do not.
Most of this seems to come from the far east.
Marine ply: must use a WBP glue, resorscinal types are the best and so would
be used. Wood used must be at least "moderately durable", with almost all
heartwood. It's not indestructible though and quality does vary. The best
stuff is known as "RNLI" marine ply and its price makes you shudder.
Sealing the edges: paint won't do. Consider a protective edging, perhaps
aluminium, set in mastic and screwed into the edge. Alternatively, cover it
with GRP. A GRP tape should do it.
How big is the sign? Go for thick ply, 19mm or above. If properly protected,
shuttering ply lasts well and does not cost an arm and a leg.
--
Regards
Peter D Jones
Southampton
Antispam: remove X from Xmudhut
Charles (Joe) Stahelin
<c.ho...@excite.co.uk> writes
>need to make up an advertising sign which hopefully
>will last a few years in an exposed site.
"Marine" is for boats and the like. There is a variety known as Far
Eastern Water Proof Bond (if I have got it right), WPB or similar, for
short. This should do you well, and is cheaper than marine ply.
Protecting the edges is always a good thing. Comes in the usual 8 by 4
ft sheets. Finish back, front and edges, with "?" coats of BourneSeal
or Yacht Varnish. If yacht varnish is used apply the high gloss variety
until satisfied then finish off with one or (if needed) two coats of
Satin or Matt.
A frame round the edges should help to protect the integrity of the
sheeting and also to protect it from wind effects - flutter and such-
like. It will be better for it if it is mounted in such a way that
there is room for rainwater to run behind it without getting trapped.
--
Charles (Joe) Stahelin,
Huddersfield, West Yorkshire, UK.
nightjar
Chris wrote in message <36C89A50...@excite.co.uk>...
>
>Any suggestions for sealing the edges as they are obviously
>prone to water ingress and rot.
Use one of the water thin resins sold as the first stage in the repair
of rotted wood. They are designed to soak deep into wood to provide a
stable base for repair materials, but also serve very well as sealants
for vulnerable areas.
Colin Bignell