In The Shop: Ear Protection Optional, But Recommended
Nov 07, 2010
Tightening disk gang bolts isn't difficult if you have two people, the correct tools and good ear protection. Gang bolt nuts tightened to anything less than "unbelievably tight" can allow disk blades and bearings to subtly work and move on the gang bolt, and no good comes from ANY movement by blades and bearings.
In the shop we use two techs and serious tools to tighten gang nut bolts. One guy uses a special mega-wrench to hold the stationary end of the gang bolt. The other guy uses a 3/4-inch or 1-inch-drive air wrench to torque the gang bolt nut. Both guys wear ear protection, because as the guy with the air wrench torques the nut, the guy on the other end sledgehammers the end of the gang bolt. The impacts of the sledge travel through the gangbolt, remove incremental slack between the blades, spools and bearings, and help reach the necessary torque on the gang bolt nut.
In the field, if a single tech has to tighten a gang bolt alone, possibly without an air wrench, it's a lot of physical labor, and a slow process. It requires rigging blocks and gear to hold the bolt wrench while using mega-cheater bars to slowly wrench tight the gang nut. Beating on the end of the gang bolt gains an eighth to a quarter turn per effort, so there's a lot of walking from end to end of the disk gang. The one-man approach is quieter than two guys using an air wrench and sledge hammer, but is a lot more time consuming and sweaty.