Unlock and swing down the gutter guard. Rotate the turret so the glass cutter is facing outwards. Remove the old wheel and clip assembly and make sure the slots in the steel block are clean and free from burrs.

Partially push the wheel in place lining up the flattened ends of the axle with its location groove, then push it fully into the holder using a piece of plastic or hard wood. Ensure the wheel and triangular clip are sitting evenly in its slot.

Try rotating the wheel, if it does so freely try scoring some glass and if necessary adjust the pressure on the wheel by following these instructions > The aim is a light continuous score line that does not appear ‘white’ and have any splinters of glass chipping out of it.

If the wheel does not rotate freely place some MDF in the machine and run the wheel up and down using light finger pressure. The wheel can be also be eased by carefully placing a blade between the side of the wheel and the edge of the triangular clip and lightly rocking the blade to free any burrs or debris from between the wheel and clip. Do this on both sides of the wheel. When the wheel turns freely, adjust the pressure if necessary as previous using these instructions>