Window Opener

Project  / Project number: 106/16  /  Status:

The challenge

Updated 25.04.2017 – the locked nuts M6 coach bolt proved to be inadequately strong and came loose after some use. A modified version using a hex M6 spacer and washers soldered to it was made and supplied to the client.

This is the design for a window opener for three cranked window handles (2 right hand and one left hand) on horizontal opening fanlight windows  that were out of reach of the client because they were across the other side of a corner bath in one case and above a dressing table for the other two.

This is the right hand handle in the bathroom.


Original design with M6 coach bolts:


New design with M6 x 50 mm Hex spacer and two M6 x 20mm diameter washers, one drilled for M2.5 screw and one bent.





The assembly was designed in SolidWorks 3D and made from wood and aluminium from the 2D drawings generated from the 3D. It could be 3D printed in ABS.

The plastic pipe was 21.5 mm nominal diameter – manufacturers products vary so have to use the matching T piece. The pipe was about 1.15 m long.

Fixings: M6 x 75mm coach bolt  with 4 nuts and 3 shake-proof washers.

M4 x 25mm pan head screw, nut and shake-proof washer to fix the block to the aluminium bar.

M4 x 30mm pan head screw, nut and shake-proof washer to fix the tube to the ring.


18 mm diameter dowel from B&Q the full length of the pipe was inserted inside the main tube to stiffen it.

The handle was a T fitting and two 75mm lengths of pipe glued in with ABS/PVC cement


The handle was fitted perpendicular to the opener ring; glued with ABS/PVC cement.

The exact position of the block on its arm has to be adjusted to work for the angle of the main pipe. It is then tightly locked by the M6 nuts and shake-proof washers either side and a locknut was also added on the outside for added security.

This design can be adapted for different handles. Different blocks may be required without the side retaining walls etc.

This is the modified design:



This is the original 3D model and the 2D drawings: