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notes are given in good faith for general guidance purposes
only
and since actual operating conditions, methods and
application
techniques are beyond our control we cannot accept
liability
for any losses however they may occur. Other help sheets & tips are available via the
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Best viewed at 800 x
600 screen resolution. This tutorial follows
the steps required to completely weatherproof a piece of plywood, as in
the process of constructing or repairing a garage or shed roof etc.
List of tools
and materials required to complete this particular job. area size of the
job = one square yard. 10% added to material quantities to allow for
waste & overhangs etc.
1. 19.8 sq/feet 1½oz glassfibre mat (2 layers)
2. 2.10kgs Lay-up resin.
3. 708grams Flowcoat.
4. 57 ml Catalyst.
5. catalyst measuring cup.
6. 70 grams pigment
7. 2" laminating brush.
8. Paddle roller.
9. 1 litre mixing bucket
10. 150ml mixing cup.
11. mixing sticks.
12. latex gloves.
13. Stanley knife.
Step
1. Clean the board ensuring it's dust and grease free. Step 2. Cut all your glassfibre mat to size (allow
1-2" overhang at all edges). Step 3. Pour out a workable amount of resin (depending on
the area you are covering, start with half litre lots, progressing to
larger quantities as you gain experience) into your mixing bucket. Step 4. Accurately measure out your catalyst
normally (2% at normal
working temperature 20ºC) add to resin. Step 5. Mix catalyst and resin using a stirring action
ensuring all resin at sides of bucket are mixed with catalyst (the
colour of un-pigmented resin usually changes slightly when thoroughly mixed
with catalyst. Step 6. Apply the catalysed resin using a brush. Step 7. Completely cover the area which will be covered by
your glassfibre mat. Step 8. Apply your first layer of glassfibre mat,
stippling with a brush to impregnate the resin into the mat, do not use
a brushing action as this can disturb the glass fibres. Step 9. Begin rolling the surface squeezing the resin
through the mat, also eradicating any trapped air pockets. Step 10. When you have fully wetted out the first layer it
will appear almost transparent with a uniform colour throughout the
whole surface. Step 11. Applying the second glass mat layer is ok now
whether or not the first has gelled, but consider that maximum bond is
achieved wet on wet. Step 12. Begin rolling and also
adding resin as necessary to completely wet out the second layer. Step 13. Allow to gel and watch carefully as
the curing process begins as in the early stages of cure it will arrive
at the "green" stage (hardening but still quite flexible). Step 14. At the "green" stage you will find it
quite easy to trim all the excess edges with a sharp craft knife, you
have to work fairly quickly as this stage only lasts a few minutes, but
if you do this it will save a lot of work at the finishing stage as when
the full cure has occurred saws files or grinders will be required to
cut and trim the edges. Step 15. When the fibreglass layers have cured, fill a
suitable container with flowcoat (finish gelcoat), add the pigment
colour of your choice (by weight up to 10% pigment) and stir thoroughly. Step 16. Add measured amount of catalyst (2%) stir
into flowcoat ensuring good dispersal into the gel. Step 17-18. Pour catalysed flowcoat onto cured laminate, then spread with a brush or roller. Step 19. Ensure a completely covered surface
including the edges with a uniform thickness 0.5mm minimum recommended. Step 20. A picture of the cured weather/waterproof
surface.