I have made a window screen using wooden strips, netting, some hardware and 3D printed parts.

It has a spring-loaded, double-herringbone pinion and rack mechanism that locks the screen into the window frame.

Description of the non-3d printed parts needed:

• 2 x M5 x 20mm
• 6 x M3 x 10 up to 12mm
• 4 x M4 x 10mm wood screws - for the corners
• wood screws 10 up to 15mm - for the netting use as many as you see fit
• 16.5 mm x 27.5 mm - wooden strips (some odd dimensions, but it was designed around what i had on hand)
• netting