The Technique of FURNITURE MAKING
LOOSE TENONS
Loose tenons for demountable structures which
Joints closed |
148 Rebated/rabbeted frames showing alternative methods
are not glued together are shown in 147:1. It shows the keyed tenon in which a single thick tenon is taken through the post, slotted and then keyed together with a tapered wedge. The slot should pass a little way into the mortise (A) so that the wedge bears against the post. This type is used on stretcher rails in reproduction oak refectory-tables, collapsible forms, etc. Figure 147:2 is the tenon and bolt, with a stub tenon entering the post and secured with a headed bolt passing through from the outside and held with a square nut in a mortise cut to allow it to enter, but not to revolve. Another example of this technique but without tenons is the handrail bolt (147:3), used for jointing two pieces of timber in the same plane, i. e. fireside rails, handrails, etc. A special double-threaded bolt is used with circular nuts (A) slotted to take a screwdriver-blade or stout punch. If only one bolt is used the ends should be prevented from swivelling round by short stub dowels, or more commonly with wire nails either side of the central bolt knocked in and pinched off leaving about 1/8 in (3 mm) protruding. The nuts are inserted in the mortises, the bolt fed through and the nuts tightened by tapping them round, after which the mortise holes are plugged. Examples of well-fitted mortises and tenons are illustrated in 148.