Window Catch

I doubt many people will need this.. but if you do.. you will know :)

I designed it to hold three different ageing UPVC windows closed. One had a broken lever (see pic).. the other two had bent frames.

I've included a fusion 3d file so that you can easily modify my model to suit your situation.

The photos should explain how this is used.

Instructions:

The neck needs to be the correct size for the gap between the window frame and your window.

Print on side (for strength) with base supports for the neck section. 50% infill worked fine for me.

My windows are not steel reinforced in the location shown in the photos. If they were I would have drilled a hole suitable for an M6 bolt and tapped the hole for the thread, however:

I used an M6x60 S/S wood screw with a 16mm diameter S/S washer which acts as a bearing. The washer is a very tight fit (I just hammered it in but it could be heated). See photo.

I drilled a small pilot hole 3.5mm and test screwed the assembled catch to the window to make sure it works as intended (check the window will open and close without hitting the catch itself).

In my case I am pretty sure the only grip the screw had was 2-3mm of UPVC which isn't really strong enough to hold the catch in place if used. In addition the screw would gradually unscrew itself anyway. With this in mind I injected self mixing epoxy through the hole until it filled enough of the void to add strength for the screw and stop it turning with the catch. This seems to work fine in my case and the windows are held closed with enough force to seal them. Obviously, being plastic, this is NOT going to stop someone prying the window open!