摘要 |
The primary members have plane external faces with subsidiary sections clipping into place to form glazing retention strips and seal supports etc. Three primary members are used for window frames, infilled panel frames and sash frames resp. The window frame member is of 'T' section with two flanges projecting from the stem, a square return at the foot and dovetailed channel formations at the ends of the return and the corresponding let (3) of the bar of the 'T'. The other primary members are of 'U' and 'h' section with dovetailed channel formations at each corner and on the bars. |