Carry out the mixture in a wheelbarrow, for example, until obtaining a firm and homogeneous paste.
Cut the metal edge using a shear or of a hacksaw to the desired length.
Deposit several studs on each side of the angle.
Then, position the metal edge and exert a light pressure to insert the edge in the coating. Carry out this same operation on each side of the opening.
Then, close the shutters and block the catch.
Use small corners out of wooden, to give the place necessary between the edges and the shutters. In general, 3mm is enough on the sides and the lintel, like behind the strap hinges.
This place is essential to allow future the correct operation of the shutters once the finished rough coat.
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