Below are starting points for common purchased items that may be used in a BOM. Any special notes, needs or requirements, just add to callout. If you are not sure what to write, check an old drawing, your supplier or purchasing department. Make sure that the callout is exact and complete so there are no mistakes or questions and the correct part is used in the assembly.
Part | Callout | Example |
Hex head cap screw (bolt) (ref) | HHCS, thread X length | HHCS, 1/2-13 UNC X 2 |
Socket head cap screw | SHCS, thread X length | SHCS, 1/2-13 UNC X 2 |
Socket head shoulder screw (bolt) | SHSS, shoulder diameter X length | SHSS, 1/2 X 2 |
Flat washer (ref) | FW, diameter (of bolt) | FW, 1/2 |
Lock washer | LW, diameter | LW, 1/2 |
Nut (ref) | HEX NUT, thread | HEX NUT, ½-13 UNC |
Bushing (not flanged) | BSHG, ID X OD X Length | BSHG, Ø.5ID X Ø.75OD X .5 |
Spring (best to have a part number) | SPRING, TYPE, OD X length, ends, notes | SPRING, COMP., Ø2OD X 6, FLAT ENDS |
Parts by number | Supplier, part, number, what ever | DODGE, BEARING, P/N123456-A |
Pin | PIN, OD X length | PIN, Ø.75 X 1 |
Cotter pin, Split pin (ref) | COTTER PIN, OD X length | COTTER PIN, Ø1/8 X 1 |