A pair of French doors made using softwood were rotting away. South facing,
they had taken a lot of weather. The bottoms had been
boarded over in an attempt to disguise the rot. The
brief, to replace them with an identical pair of doors
in oak.
Photosabove:.....
Oak and traditional joinery. A router is used to cut out
the mortises, and an inverted router set in a router table
is used to produce the tennons.
Photos above:...
When there is a moulding
running around the glass panels it is necessary to
mitre the rails into the stiles. For me, this is hardest
part of door making . The funny dark shape is a teaspoon,
the handle of which has been wedged into the joint to
separate the rail from the stile to illustrate this text.
Too much wood removed means a gap. Too little and the joint
will not close up properly. High levels of accuracy are required...
Furthermore, these mitres must be in exactly the right
positions otherwise, a rail will not sit square with
the mitreing on the opposite stile....
Photos: Above......
Final gluing up using
polyurethane adhesive. New technology in glues means that
the glue reacts with moisture in order to "go off" and then
resists moisture entirely; the joint will never break
down with damp or the ingress of water.
Photos:
Below
Close up of the door handle and mortise lock in
situ.
Photosabove:
Left close up of the door. Right the
pair of doors as fitted.
Double glazed units were fitted; the
glass is toughened glass and the inside of the inner pane is
"Pilkington K glass. This inner glass pane is
especially coated and in effect; reflects heat but
allows light in.
Because the tannic acid in the oak can cause
the sealant used in the construction of the glass units to
break down two prerequisites are necessary. The rebate for the glass is given two
coats of polyurethane to seal the wood.
Then as the glass goes in, it is separated
from the wood by a special "low modulus" sealant . The
effect is to isolate the glass units (and its adhesive) from the wood and to
prevent the ingress of water into the area around the glass.
The glass units are held in with oak glazing
bars. The glazing bars are screwed in using brass screws.
Photosabove:
Left-
view from inside. Right- drip bars screwed on using brass
screws. The finish is Sikkens Filter 7. Very expensive but
also the best possible finish. It is unlike polyurethane
because it will never flake off and it is not like Danish oil
because it is highly resistant to rain, weather and
particularly UV light. Think of Filter 7 as a resin
that becomes hard and which gradually wears away. In about 4
years time, the application of another coat of Filter 7 will
restore its protective qualities.