BS 6381:1983 pdf free.Specification for drawing boards.
This British Standard BS 6381 specifies requirements for drawing boards, for professional use and for student use, for use with tee squares, parallel-motion units and drafting machines. Appendix A gives guidance on the selection of materials.
NOTE The titles of the publications referred to in this standard are listed on the inside back cover.
2 Dimensions and designation
2.1 Depth and width. The depth and width of the boards shall be as shown in Table 1 within a tolerance of± 2.0 mm.
2.2 Thickness. The thickness of the boards shall be not less than that given in Table 1.
2.3 Designation. Boards shall be designated according to their dimensions, as shown in Table 1. The designation Al shall be completed by the word “professional” or “student” as appropriate.
3 Working edges 3.1 Opposite edges. Opposite edges shall be parallel within a tolerance of± 0.5 mm over each 1.0 m length of working edge. 3.2 Straightness. When a steel straightedge, complying with the requirements for grade A of BS 5204-2, is placed along a working edge, that edge shall not deviate from the straightedge by more than 0.25 mm over each 1.0 m length of the working edge.
4 Working surfaces
When a steel straightedge, 1.0 m long and complying with the requirements for grade A of BS 5204-2, is placed on a working surface, the surface shall not deviate from the straightedge by more than 1.5 mm, irrespective of the position of the straightedge on the surface.
5 Battens
If battens are supplied with the board, they shall extend acro flot. lecs than 80% of the cIepth of the board and shall be fixed to the board in a manner that leaves the board free to expand and contract.
6 Packaging
6.1 Professional boards. Each board shall be individually and entirely enveloped in a protective cover designed to protect the surfaces, edges and corners of the board.
6.2 Student boards. Either each board shall be packaged individually as specified in 6.1, or several boards shall be packaged together in a carton with their faces separated by a non-abrasive medium.BS 6381 pdf download.