WORKMANSHIP STANDARD WS011 - L-3 Communications

WORKMANSHIP STANDARD WS005
*Fastening Hardware Mounting *4.4.0 Fastening Hardware General
Requirements
*Fastening Hardware Application
Unless otherwise specified on the Engineering drawing, standard fastening hardware
application shall be tightened to compress split lock washers (if present) or otherwise tightened
to insure there is no relative movement between joined hardware and materials.
Locking Device
Standard fastening hardware (nuts, bolts and screws) should be assembled with some form of
locking device i.e.: lock-washers, locking-nuts, locking inserts, locking fluid etc.. These locking
devices will be specified on the drawing.
Without Locking Device
Threaded hardware such as connector jackscrews, backshells and jam nuts, captive hardware,
wedge locks etc will not have locking devices unless otherwise specified on the engineering
drawing.
Thread Extension
A. A minimum of one and one half threads need to extend beyond the threaded hardware, unless
otherwise specified by engineering drawing. Bolts and screws may be flush with the end of the
threaded hardware only where threads could interfere with other components or wires and
when locking mechanisms are used.
Thin profile nuts must comply with the minimum thread protrusion requirements.
Thread Extension
B. Should not be more than .12 inch plus one and one half threads for bolts and screws up to
1.00 inch long.
C. Should not be more than .25 inch plus one and one half threads for bolts or screws over 1.00
inch long. Condition providing that the extension does not interfere with any adjacent part and
that the designated electrical clearance requirements are met.
(Reference IPC-A-610)
10-22-2007 Page 1 of 1 WS-005-4.4.0
Printed version of this document may be obsolete. Verify revision and issue date against the on-line system.

Thread Engagement
A. Table 1
Material Minimum engagement
depth:
Steel 1 x Screw Diameter
Brass 1 1/2 x Screw Diameter
Copper 2 x Screw Diameter
Aluminum 2 x Screw Diameter
Plastic 2 x Screw Diameter
Red = Harder materials.
Blue = Softer materials
B. Dissimilar materials being fastened together shall meet the minimum engagement
requirements of the softer material as defined in table 1.
10-22-2007 Page 2 of 1 WS-005-4.4.0
Printed version of this document may be obsolete. Verify revision and issue date against the on-line system.