39 Ballymontenagh Road, Ballymena, BT42 2QG

Square Cut & Key



Square cut & key – the most common and fastest method of panel assembly. Each piece of bar is cut to length and the adjacent pieces are held together with a nylon key. Only a saw is required to produce this type of panel. However rigidity can be an issue and rubber grommets (or buffers) are commonly used in the keys to prevent rattling. This method is less suitable for special finishes as the nylon keys need to be colour matched to the profile.

The process for a basic 6 pane georgian panel is as follows:

1. Cut mullion bars to length

2. Cut transom bars to length

3. Fit 90° centre key to both ends of middle mullion bar

4. Assemble transom bars and top/bottom mullion bars to centre mullion bar

5. Fit edge keys to top/bottom mullion and transoms