A Major Aid For Door Preparation

Hammers and screwdrivers are necessary tools for locksmiths.

Locksmiths use tools as either a necessity or an advantage. Necessary tools are screwdrivers and hammers. They perform tasks that cannot be accomplished without them. Advantage tools can save time, which means saving money. Ensuring accuracy or simplifying a task usually saves time. For example, most locksmiths can install a cylindrical or tubular lock freehand using the different sized drill bits, a template or tape measure, and a drill motor. However, many if not most locksmiths use some type of an installation tool to not only simplify the installation process, but also to ensure an accurate installation. This is especially important when installing the lock onto a finished wood door. Another advantage of the installation tool is having it align the locations for the thru-bolt holes, which sometimes overlap the cross-bore opening.

Over the years, there have been many different locks introduced, each requiring unique configuration of cross bore and edge bore openings. To simplify the door preparation, improve the level of accuracy and save time, Major Manufacturing has developed a line of installation tools, jigs, and guides. These installation aids not only simplify the door preparation for the mechanical and/or electromechanical locks, but also electric strikes in wood, aluminum and hollow metal doors and frames.

The newer mechanical and electromechanical locks are more difficult to install. Additional cross bore holes must be drilled for the mounting of the locks and running the wiring. Why? The lock assemblies -- exterior and interior -- are much larger in most electromechanical locks. Because of the increased size, more cross bore holes must be drilled for mounting/thru bolting these locks. Another reason is most of the electro-mechanical locks’ wiring interconnects the exterior assembly and the interior or the latch mechanism, requiring additional cross bore holes be drilled.

Some examples of locks that have an increased number of cross bore openings are the Schlage King Cobra KC5100 Series (use HIT-119 Drill Guide), Kaba Ilco 7000 Series (use HIT-107 Drill Guide), CODELOCKS 5000 (use HIT-134 Drill Guide), Securitron SABL (use HIT-133 Drill Guide), Kaba 660/760 Cylindrical Lock (use HIT -131 Drill Guide), and the Yale E5400LN eBOSS (use HIT -132 Drill Guide).


For this article, we will install a Yale eBOSS E5400LN Series into a wooden mount using the Major Manufacturing HIT-44 “Drillmaster” to drill the cylindrical lock door preparation, and the HIT-132 drill guide to drill the wire runs and the cross bore holes for mounting the eBOSS. The machined double-sided aluminum drill guide has hardened steel drill bushings on both sides to enable drilling from both sides. Drilling from both sides limits the chances of the door splitting. The HIT-132 drill guide is designed to accommodate door thickness up to two inches.

Note: For installations that are retrofitting the eBOSS onto an existing cylindrical lock 161 door preparation, skip the steps using the HIT-44.

Step 1. Locate the height for mounting the eBOSS. According to the installation instructions, standard height for the horizontal centerline of the 2-1/8” cross bore is 40-5/16” above the finished floor.

Step 2. Attach the HIT-44 to the door's lock edge at the determined height.

Step 3. Drill the 2-1/8” diameter cross bore and the 1” diameter edge bore holes. Clean out the openings.

Step 4. Mortise out the lock edge of the door to accommodate the latch face.

Step 5. Attach the Major Manufacturing eBOSS drill guide, part # HIT-132, to the lock edge of the door using the 2-1/8” cross bore openings as alignment locations. The drill guide should align flush against the door edge.

Step 6. Use a 5/16” hex wrench to secure to HIT-132 to the door.

This content continues onto the next page...

We Recommend