The Technique of FURNITURE MAKING
Cutting mitres
The mitre-square or fixed mitre is used for marking true mitres (45°); the adjustable bevel for all other angles. Some jig or guide is necessary for sawing, and the simplest form is the wooden mitre box, easily made up either as a permanent tool or as and when required. A precision mitre-saw with hacksaw-type blade adjustable to any angle and extensively used by picture-framers is shown in 169, and the mitre - trimmer (170) which is also adjustable. Both these tools are virtually indispensable where there is much mitring to be done. For occasional
169 Cutting mitre on Ulmia mitre-saw
use the beechwood mitre shooting-block (168:15) enables mitres in the width to be accurately planed up, with the donkey's ear shooting-board (168:16) for mitres in the thickness. In cutting mitres by hand a fine saw should be used, with the cut into the moulding wherever possible, and not out of it, so that the rag of the saw is at the back or bed of the moulding and not in the face. If the tip of the moulding tends to splinter away while the mitre is being planed, a scrap piece should be inserted at the back to support the fibres, with the plane or trimmer cuts as fine as possible. Very large
170 Hand mitre-trimmer set to trim true mitre |
mouldings may have to be trimmed freehand, holding the timber in the vice and planing off with a smoothing-plane or block-plane, working diagonally and constantly checking with the mitre-square. When mitring around a carcass with front and side mouldings, complete the front moulding first and then the two sides, or two mitres will have to be fitted simultaneously if the front is left to last. If all four corners have to be mitred as with the lippings of a panel or top, simultaneous fitting cannot be avoided, and a waste piece is mitre cut and used as a checking piece at each corner. Two opposite sides are then mitred and sashcramped/clamped in position, checking for correct length with the waste piece; the contiguous mitres are then fitted. The same procedure can be adopted in gluing up. A simply made mitre-marking tool for sections moulded in the thickness which are difficult to mark with fixed mitre or adjustable bevel is shown in 171. The suggested dimensions can be varied as necessary.