C = parts.screw.cap ('data') returns every cap screw in the catalogue as a table, one row for each maker’s article in each size and length, sorted by size and length. C = parts.screw.cap ('data', NAME) returns those of the thread NAME, such as 'M5', and C = parts.screw.cap ('data', NAME, L) those of nominal length L too: every article sold as that screw, each with its property class and finish. Nothing is built.

S = parts.screw.cap ('solid', NAME, L) builds the screw as a solid.Shape whether or not anyone sells it: any thread whose head the standard defines, any length. NAME names a coarse thread by its diameter, 'M5', or any pitch, as 'M16x0.8'. The underside of the head lies on the xy plane, the head above it to z = k, the shank below it to z = -L, the socket sunk into the head with two of its corners or lobes on the x axis. S.Name holds the screw’s designation.

Name/Value pairs:

'Drive'

The socket: 'hexsocket' (alias 'allen'), ISO 4762, the default, or 'hexalobular' (alias 'torx'), ISO 14579. For 'data' it keeps that drive’s screws only; without it both come.

'Maker'

For 'data': only that maker’s articles, such as 'REYHER', in any case.

'ThreadLength'

For 'solid': the length of thread b from the end of the shank, from 0 to L; L threads it to the head. Without it the thread follows Table 1 of ISO 4762 or ISO 14579, which agree: threaded to the head up to the longest length the table threads so, and b of the table from its first length with a plain shank. A length between the two takes no default and needs 'ThreadLength'.

'Detailed'

For 'solid': true builds the screw as its standard defines it, slower: the fillet of radius r under the head, the hexalobular socket’s true outline, and the thread, cut by solid.Shape.thread. A thread to the head runs to within 3P of it, as Table 1 allows. By default (false) the shank is a plain cylinder of diameter d, the edges are sharp and the hexalobular socket is a round hole of its diameter A. Either way the socket is cut to its smallest depth t; the point is left flat, its chamfer not given by the sources.

The table has these variables, each with its unit and its description, which summary (C) lists; lengths are in millimetres:

A screw is designated by its standard’s number only when the standard’s table defines it: the size, the length and, through the length, whether it is threaded to the head. Every other screw is custom, its thread length written when shorter than l, as 'Hexagon socket head cap screw M5 x 60 x 22'.

The catalogue

Articles from REYHER, The Catalogue, edition 2020.04, English, pages 286 to 304 (steel), 547 to 551 (stainless steel), 402 and 121 (hexalobular): every article of a plain screw in sizes ISO 4762 defines, M1.6 to M64, and in lengths ISO 4762 Table 1 gives a thread for. Left out: the sizes M1.4, M18, M22, M27, M33 and M39, whose socket depth and thread form the sources do not give; the lengths M3 x 22, M4 x 28, M6 x 32, M20 x 75 and M24 x 85, which fall between Table 1’s threaded and plain shank lengths; and an M 25 x 50 printed in article 04762.810, a thread ISO 261 does not have. The two articles of 8.8FT are threaded to the head at every length. Article 00912.814, filed under DIN 912, is the ISO 14579 screw by REYHER’s own note.

Heads, sockets and thread lengths from ISO 4762:2004 Table 1, read in IS 2269:2006, which agrees with REYHER’s Technical Information (2019, TI-12). Hexalobular heads and thread lengths from TI-12, socket numbers and depths from DIN EN ISO 14579:2011 as reproduced by fasten.it and fasteners.eu, which agree; its lengths and thread form from ISO 14579:2011, read in GOST R ISO 14579-2015, which agrees with GOST R ISO 14579-2009 and fasteners.eu.

See also: parts.bearing.deepgroove, parts.dowel, parts.key

Source Code: parts.screw.cap