1、BRITISH STANDARD BS 3823:1990 Specification for Grading of ash and hickory wood handles for hand toolsBS3823:1990 This British Standard, having been prepared under the directionof the Machine, Engineers and Hand Tools Standards Policy Committee, waspublished under the authorityof the Board of BSI an
2、dcomes into effect on 31May1990 BSI 09-1999 First published January 1965 Second edition May 1990 The following BSI references relate to the work on this standard: Committee reference MTE/15 Draft for comment 87/71447 DC ISBN 0 580 17808 0 Committees responsible for this British Standard The preparat
3、ion of this British Standard was entrusted by the Machine, Engineers and Hand Tools Standards Policy Committee (MTE/-) to Technical Committee MTE/15, upon which the following bodies were represented: British Coal Corporation British Telecommunications plc Consumer Policy Committee of BSI Department
4、of Trade and Industry Mechanical Engineering and Manufacturing Technology Division (Mmt) Electricity Supply Industry in England and Wales Engineering Equipment and Material Users Association Federation of British Engineers Tool Manufacturers Federation of British Hand Tool Manufacturers Handle Manuf
5、acturers Association Institute of Carpenters Institution of Production Engineers Ministry of Defence The following body was also represented in the drafting of the standard, through subcommittees and panels: Forestry Commission Amendments issued since publication Amd. No. Date CommentsBS3823:1990 BS
6、I 09-1999 i Contents Page Committees responsible Inside front cover Foreword ii Section 1. General 1 Scope 1 2 Definitions 1 3 General 4 Section 2. Grading 4 Ash non-striking tool handles 6 5 Ash striking tool handles up to and including425mm in length 6 6 Ash striking tool handles greater than425mm
7、 in length 6 7 Hickory striking tool handles up to and including1050mm in length 6 8 Marking 8 9 Moisture content 8 Appendix A Determination of slope of grain 9 Appendix B Recommendations for storing wood handles 9 Figure 1 Illustration of wavy grain:half size 4 Figure 2 Illustration of curly grain:
8、full size 5 Figure 3 Swivel-handled scribe for determination of slope of grain in wood 9 Figure 4 Use of scribe 10 Figure 5 Measurement of slope of grain 10 Table 1 Sloping grain deviations for handles of450mm to1050mm in length 7 Table 2 Sloping grain deviation for handles above1050mm in length 7 T
9、able 3 Permissible blemishes in ash non-striking tool handles 7 Table 4 Permissible blemishes in ash striking tool handles up to and including425mm 8 Table 5 Permissible blemishes in hickory striking tool handles up to and including1050mm 8 Publications referred to Inside back coverBS3823:1990 ii BS
10、I 09-1999 Foreword This British Standard has been prepared under the direction of the Machine, Engineers and Hand Tools Standards Policy Committee and at the request of users and manufacturers of hand tools. It supersedes BS3823-1:1965which is withdrawn. In producing standards for tools which are pr
11、ovided with wood handles it has been customary to insert a requirement stating that the timber has to be well-seasoned, tough, straight grained; free from knots, shakes and other defects; and with a controlled moisture content at the time of manufacture. Such requirements have been criticized as bei
12、ng insufficiently indicative of the exact quality of material required, being too stringent in demanding theoretically perfect timber. This British Standard provides criteria by which handles are accepted or rejected relative to grades and thus gives clearer definition on grading for the various han
13、d tools standards which, where appropriate, will make reference to this document. In this way the fullest information will be available to inspectors of the tools and disputes on quality may be avoided. A British Standard does not purport to include all the necessary provisions of a contract. Users
14、of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages1to10, an inside back cover and a back
15、 cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS3823:1990 BSI 09-1999 1 Section 1. General 1 Scope This British Standard specifies criteria for use in grading handles inten
16、ded for fitting to general purpose hand tools including agricultural and striking tools. The scope covers only unbleached handles manufactured from natural ash (Fraxinus excelsior and Fraxinus americana) and from any of the four true species of hickory as follows: shagbark hickory (Carya ovata); she
17、llbark hickory (Carya laciniosa); pignut hickory (Carya glabra); mockernut hickory (Carya tomentosa). The standard specifies the requirements for freedom from defects and the permissible blemishes which are tolerable in respect of the various grades of handles. A method for determining the grain slo
18、pe and recommendations for storing wood handles are given in the appendices. NOTEThe titles of the publications referred to in this standard are given on the inside back cover. 2 Definitions For the purposes of this British Standard thedefinitions given in BS6100-4.1to BS6100-4.4apply together with
19、the following. 2.1 General terms 2.1.1 annual ring 1) a growth ring corresponding to an annual period of growth 2.1.2 air-seasoning 1) the process of drying timber by exposure to natural atmospheric conditions 2.1.3 blemish 1) any feature that mars the appearance of timber or other material without
20、affecting its technical quality 2.1.4 conversion 1) the process of sawing timber from the log 2.1.5 defect 1) any feature that lowers the technical quality or commercial value of timber or other material and may therefore lead to its rejection or to its relegation to a lower grade 2.1.6 density 1) t
21、he mass per unit volume, usually expressed in kilograms per cubic metre (or kg/m 3 ) 2.1.7 fabrication forming by any machining process, following conversion 2.1.8 fibres 1) the long narrow elements (cells) of which wood and certain other plant tissues are largely composed 2.1.9 grain 1) the general
22、 direction or arrangement of the fibres, e.g. spiral grain, straight grain 2.1.10 kiln 1) a chamber used for seasoning and conditioning timber, in which the temperature and humidity of the circulating air can be suitably varied and controlled 2.1.11 kiln-seasoning 1) the process of drying timber in
23、a kiln 2.1.12 moisture content 1) the amount of moisture in timber or other material expressed as a percentage of its oven-dry weight 2.1.13 seasoning 1) the process of drying timber to a moisture range appropriate to the conditions and purposes for which it is to be used 2.1.14 sound 1) free from d
24、ecay 2.1.15 straight grain 1) grain which follows a course generally parallel to the longitudinal axis of the piece 1) Repeated from BS6100-4.1.BS3823:1990 2 BSI 09-1999 2.2 Natural defects, blemishes and imperfections 2.2.1 abrupt dipped grain local deviation of the grain from its general direction
25、 of more than5mm over a distance not greater than100mm 2.2.2 bird-peck 2) a small hole or patch of distorted grain, sometimes associated with discoloration, attributed to the action of birds 2.2.3 blackheart 2) an abnormal black or dark brown discoloration which may occur in the heartwood of certain
26、 timbers. Not necessarily associated with decay 2.2.4 brashness 2) a condition that causes wood to be relatively low in shock resistance (brittle). Under load, brashy wood fails abruptly at comparatively small deflexions with little or no splintering 2.2.5 curly grain 2) grain occurring in irregular
27、 curves, qualified as slight, medium or severe curly grain (see Figure 2) 2.2.6 decay 2) decomposition by fungi and other micro-organisms resulting in softening, progressive loss of strength and weight and often a change of texture and colour 2.2.7 flecks 2) small spots, dapples, or marks caused by
28、rays or other anatomical features, local irregularities in the grain or natural deposits of gummy or mineral matter 2.2.8 heavy stain pronounced discolorations, predominantly blue, occurring in specks, spots, streaks and patches 2.2.9 knot 2) a portion of a branch enclosed in the wood by the natural
29、 growth of the tree 2.2.10 large streaks lines of discoloration greater than1mm wide extending along the grain 2.2.11 light stain slight discolorations of any colour other than the natural colour of the wood, which do not impair the appearance of the handle 2.2.12 medium streaks lines of discolorati
30、on greater than 1 mm wide extending along the grain for more than one-third of the length of the handle 2.2.13 pin knot 3) a knot6mm or less in diameter 2.2.14 pin twig knot a knot less than3mm in diameter 2.2.15 pin twig mark a mark (usually the termination of a pin twig knot) less than2mm in diame
31、ter 2.2.16 pith 2) the central core of a stem consisting chiefly of parenchyma or soft tissue 2.2.17 shake 2) a separation of the fibres along the grain due to stresses developing in the standing tree, or in felling or in seasoning 2.2.18 slight dipped grain local deviation of the grain from its gen
32、eral direction, of not more than5mm over a distance not greater than100mm 2.2.19 sloping grain (diagonal grain) 2) grain which is at an angle to the longitudinal axis of the piece, owing to the method of conversion 2.2.20 small streaks threadlike lines of discoloration extending along the grain for
33、not more than one-third of the length of the handle 2) Repeated from BS 6100-4.1. 3) Repeated from BS6100-4.3.BS3823:1990 BSI 09-1999 3 2.2.21 sound knot 4) a live knot free from decay, solid across its face, and at least as hard as the surrounding wood. See2.2.24 2.2.22 spiral grain 4) grain which
34、follows a spiral course in one direction around the stem 2.2.23 stain 4) discoloration or variation from natural colour due to fungi, chemical action or other causes 2.2.24 unsound knot 4) a knot not solid across its face or softer than the surrounding wood due to decay or other defects. See2.2.21 2
35、.2.25 wavy grain 4) grain in fairly uniform waves or tipples, qualified as slight, medium or severe wavy grain (see Figure 1) 2.2.26 worm 4) any wood-boring organism (chiefly insects but including marine borers) that attacks wood, producing holes or tunnels or similar damage 2.2.27 wormhole 4) a hol
36、e or tunnel, irrespective of size, caused by worm 2.3 Defects, blemishes and imperfections introduced in seasoning, conversion and fabrication 2.3.1 case-hardening 4) the condition existing in timber in which the outer layers have undergone some drying and become set without corresponding shrinkage,
37、 causing stress between the inner and outer layers 2.3.2 chip-marks 4) indentations on the finished surface of timber made by chip fragments that have been carried round on the planing knife edges from the preceding cut. They may also be caused by chips being impressed by the rollers or pressure gui
38、des of a planning machine 2.3.3 collapse 4) flattening or buckling of the wood elements during drying which becomes manifest in excessive and/or uneven shrinkage 2.3.4 failure to clean up the unmachined surface area on a handle not completely formed in machining 2.3.5 machine burn 4) darkening or ch
39、arring of wood due to excessive friction during conversion or machining 2.3.6 split 4) a separation of the fibres along the grain forming a crack or fissure that extends through the piece from one surface to another 2.3.7 torn grain 4) tearing of the wood below the finished surface by the action of
40、a cutter or other tool 2.3.8 twist 4) spiral distortion 2.3.9 woolly grain 4) the condition of a machined surface on which the fibres have been dragged up by the cutter instead of being cut cleanly 4) Repeated from BS 6100-4.1.BS3823:1990 4 BSI 09-1999 3 General All grades of handles shall be subjec
41、t to the following. a) The handles shall be properly air-seasoned or kiln-seasoned and apart from the permissible defects, blemishes and imperfections listed in respect of each grade, shall be sound and free from detrimental defects arising from the following causes: 1) natural defects, blemishes an
42、d imperfections (see2.2); 2) defects, blemishes and imperfections introduced in seasoning, conversion and fabrication (see2.3). b) Handles shall be finished smooth and free from any projection or defect which may be injurious to the hands. c) When measured in accordance with Appendix A the grain of
43、each handle shall be generally straight, or diagonal within the limits and permissible variations specified relative to each grade. Figure 1 Illustration of wavy grain: half sizeBS3823:1990 BSI 09-1999 5 Figure 2 Illustration of curly grain: full sizeBS3823:1990 6 BSI 09-1999 Section 2. Grading 4 As
44、h non-striking tool handles The handles shall be graded in accordance with the following. a) Density. The density of the material shall be determined at the time of manufacture. The density, determined at a moisture content of not less than14%and not greater than16%, shall be not less than the follo
45、wing. Grade A handles: 670 kg/m 3(42 lbs/ft 3 ) Grade B handles: 610 kg/m 3(38 lbs/ft 3 ) Grade C handles: 510 kg/m 3(32 lbs/ft 3 ) b) Annual rings. The number of annual rings per25 mm of radius shall be within the following ranges. c) Sloping grain. The general direction of the grain shall not devi
46、ate by more than the limits given in Table 1 and Table 2 when measured in accordance with Appendix A. d) Permissible blemishes. The number of blemishes permitted in any one handle, or defined length of handle; their dispersal and disposition shall be given in Table 3. e) Colour. The colour requireme
47、nts for grades A and B shall be as follows. Grade A handles: white, light brown, or light red, or a mixture of white, light brown and light red which shall blend uniformly. Grade B handles: white, or white with the remainder light brown, light red, red, or brown, or a mixture of these colours which
48、blend uniformly. Grade C handles: no limitation. NOTEApart from the requirements stated for grades A and B coloration should not be regarded as grading criteria unless stated in the order or contract. 5 Ash striking tool handles up to and including425mm in length The handles shall comply with the fo
49、llowing. a) Density. The density, determined at a moisture content of not less than14%and not greater than16%, shall be not less than610kg/m 3 . b) Annual rings. The number of annual rings per25mm of radius shall be not less than5and not more than16. c) Sloping grain. The general direction of the grain shall not deviate from the longitudinal axis of the handle by more than25mm in500mm when measured in accordance with Appendix A. d) Permissible blemishes. The number, dispersal and disposition blemishes in any one handle shall be as given in Table 4
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