Preparation of jambs

It is recommended that sash material in excess of 45mm nominal thickness is used.

Jamb thickness should be in excess of 50mm

A groove must be cut for the entire length of the inside of the frame. This will eventually hold the two pieces of aluminium channel.

The measurements for this groove are shown opposite.

The right hand unit will always power the bottom sash with the left unit powering the top sash.

Establishing the position of the area to be cut, can be done by positioning the sash in the frame, and marking the midpoint of the sash thickness. The gap in the aluminium channel, will also occupy the point centrally.

When fitted the aluminium channel will sit within the frame with the gap exposed and the drilled flange facing the parting bead.