Boning Rods: Three Identical T-Rods, 3 ft × 3 in × ½ in, Baker 1919

Boning rods are three identical T-shaped rods for setting out a level line or an even fall by eye. Paviors used them, and drainers found them indispensable. This is the size given in Baker's surveying textbook: 3 feet long, 3 inches wide, ½ inch thick, with a cross head about 6 inches long. Drainers usually made them longer. Source: T. Baker and F. E. Dixon, Land and Engineering Surveying, 23rd ed., Crosby Lockwood, London 1919, p. 106. The cross head's section, the fixing and the tools are ours. The picture shows boning rods set out for field drains (Alan Murray-Rust, CC BY-SA 2.0).

مبتدئ

1 hour

التعليمات

Cut three equal rods

Saw three rods 3 ft (914 mm) long from board 3 in (76 mm) wide and ½ in (13 mm) thick. They must be exactly alike: square the ends and plane them to the same length. For drains, make them longer, all to the same length.

المواد لهذه الخطوة:

لوح صنوبر1 as required

الأدوات المطلوبة:

منشار يدوي

فارة يدوية

زاوية نجّار ثابتة

مسطرة

قلم رصاص

Cut three cross heads

Cut three cross heads about 6 in (152 mm) long. Ours: from the same board, with square, straight top edges.

المواد لهذه الخطوة:

لوح صنوبر1 as required

الأدوات المطلوبة:

منشار يدوي

فارة يدوية

زاوية نجّار ثابتة

مسطرة

Fix the heads square

Fix each head across the top end of a rod, centred and square to it, to make a T. Ours: glue and two nails. Check that the three rods stand exactly the same height to the top of the head.

المواد لهذه الخطوة: