A bolt that loses its clamping force is next to useless, and many of today’s common methods for securing bolts fall in that same category, according to the engineers at Nord-Lock Inc., Muskegon, Mich.

Often, the quick solution is to use lockwashers or thread-lock compounds. A more-permanent, less-costly solution from Balax Inc., North Lake, Wis. (www.balax.com), is to thread the hole with their ...