Manual of Purpose-Made Woodworking Joinery

Glazing bars 83

GLAZING BARS

Figures 5.9(c)(d)(e): For single- glazed internal doors,

the bars are usually moulded with the traditional

ovolo mould, but other designs can of course be used.

A point to bear in mind with these relatively slender

bars is that there are three methods of cross- jointing

them and each of the methods creates a lessening of

the bars’ strength in one way or another. The most

preferred method – and no doubt the strongest of

the three – is where the lay bars (horizontal bars) are

mortised and the vertical cross-bars are stub- tenoned

and scribed to them. The three methods of jointing

cross bars are shown below at (c), (d) and (e). The

main reason for mortising the lay bars (and not the

vertical bars) is to create a continuous, supported

ledge for the glass to sit on – although there are

exceptions to the rule, especially on double- hung sash

windows, where the vertical bars would be mortised

to retain continuity and give support to the slender

meeting rails.

Glazing- bar template

Figure 5.9(f ): Machine- planed, glazed- door compo-

nents are usually ovolo- moulded and rebated after

they have been through- mortised, blind- mortised,

tenoned, stub- tenoned and machine- scribed, but the

sequence of operations for hand- made joinery differs.

After being marked out, mortised, part- tenoned

(ripped down, not shouldered), ovolo- moulded and

rebated, the tenons’ shoulders are then cut and the

ovolo scribes are made. The best technique for the

hand- scribing – with a mitre template, chisel and

gouge – has already been covered in Chapter 3 and

Chapter 4, but using a gouge on the glazing bars is

impractical. So once the outline of the ovolo scribe has

been formed by chisel- paring against the template, I

its horizontal abutments to the rails. Instead of being
square, the bead is returned across the grain and
mitred in the corners. This is usually done – contrary
to a possible shrinkage problem – by rebating the top-
and bottom- edges to accommodate a planted, glued-
on bead, as illustrated at (c) and (d) above.

GLAZED DOORS

Figure 5.9(a)(b): Glazed doors are related in most
respects to all of the details covered here concerning
panelled doors, with the obvious exception that the
panels are replaced with glass – either single or double-
glazed sealed units – and this will always have planted
beads on one or both sides. Nowadays, the door’s
glazing, if positioned less than 1.5m above the floor,
would have to be safety glass. Another consideration
is that glazed doors with large glazed areas (especially
areas with large double- glazed sealed units), should
have 3mm- thick plastic ‘setting- blocks’ positioned
under and above the units diagonally and ‘locating-
blocks’ positioned adjacent to these on each side.

(a) (b)

Figure 5.9 Positions of the 3mm- thick plastic setting- and
location- blocks against the glass: (a) for left- hand side-
hung doors and (b) for right- hand side- hung doors.

(c) (d) (e)

Figure 5.9: Pictorial views of

cross- jointing to short pieces of

ovolo- moulded glazing bars;

(c) the lay bar is mortised to

receive the stub- tenoned and

scribed vertical bars; (d) the

lay bar is cross- halved and

scribed to receive the opposite

cross- halved vertical bar; and

(e) the lay bar is cross- halved

and mitred to receive the oppo-

site cross- halved and mitred

vertical bar.