The Schlage 40-227 is the OEM door preparation installation template for the Schlage L Series mortise lock family. It is the physical template guide  not a paper printout  used by locksmiths, door hardware contractors, and facility maintenance teams to accurately mark, position, and drill the mortise pocket, cylinder opening, spindle holes, and through-bolt holes required for a correct L Series installation. The Schlage L Series Service Manual explicitly references the Door Preparation Manual and Template Guide for all metal door applications, and the 40-227 is that referenced tool. This template is also required for any L Series installation where door reinforcement positioning must be accurately located before cutting.

The 40-227 is listed in the Cylinders and Keys category but is primarily a door prep tool. It belongs with the installation kit for any new L Series mortise lock job, not just cylinder work.

Schlage L Series Door Preparation: What the 40-227 Template Covers

The L Series template index includes preparation guides for three primary trim configurations, all covered under the 40-227 tool:

L1 (Rose Trim, Metal Door): The rose trim template covers L9000 and L400 Series installations with standard round or square rose trim on hollow metal doors. Metal doors require reinforcement behind the mortise pocket to support the lock case. The L Series Service Manual specifies that "suitable reinforcement is required to support the lock case in the center of the door and to prevent the door from compressing"  the 40-227 positions the reinforcement opening and the lock pocket together.

L2 (Escutcheon Trim, Metal Door): Escutcheon trim uses a larger trim plate that spans both the lever and cylinder positions. The template for escutcheon provides both the inside and outside escutcheon hole patterns along with the mortise pocket location in a single setup, allowing both faces of the door to be prepped from the same reference.

L3 (Wood Door): Wood door preparation follows a different drilling approach from hollow metal, using wood screw fasteners and a different back-set confirmation procedure. The 40-227 template set covers this application separately.

One important limitation: the 40-227 is not for HSLR (High Security Ligature Resistant) trim applications. Schlage's documentation specifies that HSLR trim requires a dedicated template  L965 for rose HSLR and L966 for escutcheon HSLR  which are separate from the 40-227.

Schlage Door Prep Template: L Series Mortise Lock Dimensions

The L Series lock case dimensions that the 40-227 template positions around are: case size 4-7/16" x 6-1/16" x 1" (113 mm x 154 mm x 25 mm), backset 2-3/4" (70 mm), lock front 1-1/4" x 8" x 7/32". Standard door thickness for the L Series is 1-3/4" (44 mm), with an acceptable range of 1-3/8" (35 mm) minimum to 2-1/2" (64 mm) maximum. Doors outside this range require special installation instructions beyond the standard template guide.

For electrified L Series installations (L9000EL/EU, LM9200, and MLR chassis), the template phase is also when wire routing provisions must be planned. Power transfer unit and wiring are not furnished with the lock  the door prep stage is when conduit paths, hinge-mounted power transfer units, and low-voltage wire channels through the door edge must be established before the mortise pocket is cut.

For lead-lined door applications, add 1/8" (3 mm) to the width of the mortise cutout per Schlage's specification when using this template.

Schlage Door Prep Tools: Template vs Drill Guide Systems

The 40-227 is the OEM Schlage template for the L Series. Third-party systems such as the Major Manufacturing HIT-66-282 and PRO-LOK L Series PRO template also prep for L Series installations using after-market aluminum drill guides with hardened steel bushings. The 40-227 is the OEM Allegion tool specified directly in the Schlage L Series Service Manual and Door Preparation Manual, making it the reference standard for warranty-backed installations and the tool of record when job specifications require OEM tooling.

SecurityParts stocks OEM Schlage L Series installation tools and parts.