Dump and bolt, generally termed dump fastenings, was very prevalent in H.M. service a few years since; but letterly a reaction in favour of treenails appears to have set in, dumps being not so frequently used. Possibly the considerations of weight and cost have influenced this change.
Lloyd's rules still show a decided preference for dumps as compared with treenails. This is perhaps due to the greater durability of the former, for a thorough treenail has considerably more holding power, so long as it remains sound, than a dump or short bolt, which lacks the advantage of the clenched point, the great recommendation of through metal fastenings. …
… Special care is required in driving treenails in order to avoid "crippling" them, as in such a case it is impossible to drive them any further, and they must be either driven or bored out, and their places supplied by others, which are generally less efficient than if driven through in the first instance. Treenails should be of well seasoned, sound oak timber, and cut with the grain; for if the fibre is cut across it is impossible to obtain efficient fastening.
Thearle, Samuel J.P.: Naval Architecture: An Elementary
Treatise on Wood, and Iron Ship-building.
William Collins, Sons & Co., London, 1874. 12mo, 13.5x8 cm, 138 pp, ill. & 4to, xlvi plates on 19 sheets.
Collins' Elementary Science Series.
Transcribed by Lars Bruzelius
Sjöhistoriska Samfundet | The Maritime History Virtual Archives | Shipbuilding | Fastenings.
Copyright © 1996 Lars Bruzelius.