1.
Electrically isolate and remove rollers or remove fitting plates to allow full
access (depending on type).
2.
Strip existing grit with an angle grinder, grit blast or needle gun.
3.
Strip the roller surface to bare metal.
4.
Clean the roller with a solvent cleaner to ensure no oil or grease remains in
the metal.
5. Regrind to
eliminate any solvent cleaner smear film. Wipe over with a clean White Cloth.
6.
Wipe thoroughly again with the White Cloth - if any dark marks appear on the White
Cloth repeat steps 4 - 6 until the cloth remains perfectly white - this is the
secret of success - any dirt left on the roller, no matter how little, with reduce
the resin bond and lead to bald patches, where the resin has fallen off the roller.
6.
Lay clean cardboard under the roller to catch aggregate (grit) that falls off
during coating, for re-use.
7.
Heat the rollers with dry heat - use electrical heaters with fans. Avoid gas heating
(particularly Propane), because of the water produced, which can cause condensation
on the roller and loss of adhesion. Maintain background heat until the resin is
completely hard. This may take up to 2 days during cold weather. Lack of heat
may also allow condensation to form on the resin and the aggregate (grit) may
then fail to bond properly.
8.
Apply Thixotropic Epoxy Adhesive with a smooth plastic spreader or brush, to a
depth of at least 75% of the average diameter of the aggregate (grit), typically
Grade 12, 2mm - 3mm, or Grade 16, 1mm - 2mm, or Mixed Grade
1mm - 3mm.
9. Apply clean,
dust free Aggregate (grit) to the adhesive so that cover is complete, with some
excess. Pat the aggregate (grit) into the resin very firmly with a clean wooden
or metal object (plastering float, batten, cricket bat), or use a piece of clean
hard plastic material. It is not necessary to apply another coat of resin, as
long as the first coat is thick enough and the aggregate (grit) is fully bedded
in. The grit must only protrude out of the resin by 1/4 of its average diameter
- for example, a 3mm grit should only stick above the resin by about 0.75mm. If
too much of the grit shows above the resin the bond will fail and the grit will
be torn out of the resin layer, leaving bald patches.
10.
Leave to cure for at least 24 hours, subject to temperatures being above 15 degrees
C at all times. Maintain the heating for the whole period.
11.
Clean and grease the end bearings and re-fit the rollers.
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buy Resin click here
Try
to do this job in the Summer months.
In
cold weather you must keep the rollers above 5 degrees C. Below 5 degrees the
resin curing will slow and curing will be delayed.
On
cold, damp days condensation on the rollers or on the resin can reduce resin and
grit adhesion, so screen off the area to prevent draughts and warm up with heaters
in the pit overnight.
In
Winter adjust the resin temperature by placing the pots of resin in warm water.
For
cleaning, use cellulose thinners, epoxy thinners, or trichlorethylene.
To
save grit, make a simple trough out of cardboard. Remove the side plates on Brake
Rollers, & fit the 'catcher'.
The
Rollers MUST NOT BE USED until the coating is really hard. Make a test
piece (of metal or wood) when the resin coating is complete. Coat the test piece
with resin, without grit, and leave next to the gritted area. Test by first thumb
pressure and then with a screwdriver before using the roller. When hard, the coating
still continues to gain strength over several days, so build up the work load.
Using
the Roller too early, before the resin is properly cured, is a false economy -
you will lose your coating and have to repeat the process.
Available
in 400cc and 1000cc (1 litre) packs, applied at about 2 to 4 litres per square
metre.
Supplied in two
coloured parts, vivid blue and cream - makes mixing easy - when the colour is
an even light blue/grey the product is properly mixed.
How
do I calculate the roller area?
Roller
Area = Diameter of Roller in Metres x 3.142 x Width of the roller in Metres
Example:
Diameter 300mm = 0.3 metres, Width 1.5 metres
Calculation:
0.3 x 3.142 x 1.5 = 1.41 square metres roller area
Resin
volume needed: say at 2 litres per square metre = 2.8 litres = 3 packs of 1 litre.
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buy resin click here for Resins Shop
