Cylindrical locks parts and diagrams are the starting point for every field technician or facility manager who needs to replace a component without replacing the full lockset. The Schlage ND Series is the standard commercial cylindrical lock in North America, carrying ANSI/BHMA A156.2-2011, Series 4000, Grade 1 certification and UL listing for 3-hour fire doors (single 4'0" x 10'0", pair 8'0" x 10'0"). The ND Series service manual published exploded view diagrams that broke the lock into its ten primary visible components: Adjustment Plate, Outside Lever, Chassis, Latch, Strike, Anti-Rotation Plate, Optional Spacer, Mounting Screws, Inside Lever, Rose, and Inside Spring Cage. Understanding what each of these components does, what fails first in each category, and how the model number determines which parts apply to a specific installation is the knowledge base that makes parts sourcing accurate and fast.

Reading the Schlage ND Series Exploded View Diagram

The exploded view diagram in the ND Series service manual shows all ten components separated along the axis of the door, from the outside lever on the left to the inside lever and spring cage on the right, with the chassis and latch assembly in the center. This layout directly corresponds to the physical installation sequence and is the fastest way to identify a failed component visually.

Here is what each component does:

Outside Lever: The lever handle on the exterior side of the door. Lever styles for the ND Series include ATH (Athens), BRK (Boardwalk), BRW (Broadway), LAT (Latitude), LON (Longitude), OME (Omega), RHO (Rhodes), SPA (Sparta), and TLR (Tubular). Dimensions vary by style: Athens is 4.56 inches wide by 3.31 inches projection, Boardwalk is 4.94 by 3.06, Omega is 5.06 by 3.31. The Rhodes lever includes an optional breakaway feature that allows the handheld portion to separate from the shank under extreme torque, protecting the spring cage and locking mechanism from forced entry.

Chassis: The internal body of the lock that houses the locking mechanism, the cylinder interface, and the latch retractor. The chassis determines the lock function. Schlage produces separate chassis for each ND Series function (ND10, ND12, ND30, ND40, ND50, ND60, ND70, ND80, ND96, and more). Chassis are not interchangeable between functions.

Latch: The spring-loaded bolt that projects from the door edge and engages the strike on the door frame. Standard backset is 2-3/4 inches. Short backset is 2-3/8 inches. For 5-inch backset, a 43-005 extension is available. The latch includes a slide clip that the installer must engage correctly during installation: "Push latch to center of slide" is a critical step in the ND Series installation instructions that is frequently missed and produces misalignment in the latch bolt.

Strike: The frame-mounted receptacle for the latch bolt. The default Schlage ND Series strike is 10-025: ANSI, no box, 1-1/4 inch by 4-7/8 inch. Finish must be specified. For fire-rated assemblies, a T strike is available. For applications requiring a deeper pocket, a box strike provides additional latch engagement depth.

Anti-Rotation Plate: A thin metal plate that prevents the chassis from rotating inside the door bore under lever torque. On the ND Series, the anti-rotation plate tab must be aligned with the indent on the hub during installation. Misalignment produces a lock that drifts out of position over time.

Optional Spacer: Schlage provides spacers for ND Series locks installed on doors other than the standard 1-3/4 inch thickness. No spacer is required for 1-3/4 inch doors. Spacers are required for 1-3/8 inch doors. For 1-5/8 inch, 2 inch, or 2-1/8 inch doors, the adjustment plate must be repositioned rather than using spacers.

Rose: The circular cover plate that conceals the mounting hardware and the through-bore hole on the door face. Standard ND Series rose diameter is 3.44 inches. The rose is available in multiple finishes and must be finish-matched when ordering a replacement.

Inside Spring Cage: The spring cage assembly on the inside of the lock that provides lever return force and contains the button or thumbturn mechanism for inside lever control functions. When an inside lever is floppy or fails to return to horizontal, the spring cage is typically the failed component.

Mounting Screws: Two screws that draw the inside and outside trim together through the door thickness. Length must match the door thickness. XN12-012 provides standard trim chassis spacers. XN12-307 provides lead-lining spacers for special applications.

Adjustment Plate: The plate that allows the outside lever assembly to be positioned correctly relative to the door face. On ND Series locks manufactured after January 31, 2017, the adjustment plate design changed. Parts for pre-2017 and post-2017 locks are not fully interchangeable.

ND Series Function Designations: What They Mean for Parts

The ND Series function number is part of the model number and determines which chassis applies and whether electrified options are relevant.

ND10: Passage function. Latch retracted from either side at all times. No locking function. No cylinder outside.

ND12: Exit lock. Outside lever fixed (cannot retract latch). Inside lever always free. Key unlocks outside lever from outside. Electrified versions: ND12EL (electrically locked, fail safe) and ND12EU (electrically unlocked, fail secure).

ND30: Privacy lock. Push-button on inside locks outside lever. Emergency coin release from outside.

ND40: Bedroom/bath privacy. Push-button on inside locks outside lever. Emergency pin tool release from outside.

ND50 and ND53: Entrance lock. Outside lever locked/unlocked by key. Push-button on inside controls outside.

ND70: Classroom function. Key outside locks and unlocks outside lever without opening door. Inside lever always free.

ND80: Storeroom function. Outside lever always inoperative. Entry requires key only. Inside lever always free.

ND96: Combination entrance and storeroom. Available with electrified options (ND96EL and ND96EU). RX (request to exit) switch available on ND10, ND12, ND80, ND81, and ND96 functions.

Cylinder Types and Why They Affect Parts Ordering

The cylinder suffix in the ND Series model number determines which cylinder is installed:

Standard cylinder (no suffix): Conventional Schlage mortise cylinder. Uses SC1 5-pin or SC4 6-pin keyway. The standard residential and commercial specification.

FSIC (Full-Size Interchangeable Core): Allows the core to be removed and re-keyed without disassembling the lock body. The core uses a control key to insert and remove the core from the housing.

SFIC (Small Format Interchangeable Core): Best Primus-compatible small format IC standard. The core is smaller than FSIC. Common in institutional environments where a master key system uses SFIC throughout the building.

For keyed IC outside levers (FSIC only), the ND Series installation instructions include a specific note: "IMPORTANT! DO NOT install IC cylinder! Follow steps in ND-Series Timing Guide!" The timing guide must be consulted before cylinder installation on keyed IC functions. Ignoring this step is the most common cause of a new ND Series installation that does not function correctly after assembly.

The electrified ND Series uses a motor, not a solenoid, to provide quiet operation and energy efficiency. Maximum current draw is 0.24 amp, allowing more locks to run from a single power supply. The low 0.010 amp holding current eliminates the risk of lever heating in long-duration electrically locked applications.

Lock Timing and What It Means for Servicing

Certain ND Series functions require timing, meaning the position and adjustment of internal components must be set before the lock will operate correctly. Functions requiring timing are listed in the ND Series Timing Guide (P517-432), which ships with the lock.

On serviced locks where the chassis has been disassembled, the timing must be reset before the lock is reinstalled. A lock that functions mechanically but does not respond to a key, or one that operates in the wrong direction, almost always has a timing error rather than a failed component.

Sourcing ND Series Parts Accurately

Security Parts organizes the complete cylindrical locks parts and diagrams catalog with model-specific pages for the Schlage ND Series. Every parts page carries an interactive diagram aligned to the exploded view format used in the official ND Series service manual. Navigate to the function designation (ND10, ND12, ND70, etc.), open the diagram, identify the failed component visually, and confirm the part number before ordering.

The Schlage brand catalog extends this organization across every Schlage line beyond the ND Series. Pre-order compatibility support at 845-935-0301 or sales@securityparts.com, particularly for confirming whether a lock is pre-2017 or post-2017 manufacture before ordering an adjustment plate or inside spring cage.

Conclusion

The Schlage ND Series diagram shows ten components. Each one has a specific function and a specific failure mode. The chassis is function-specific and cannot be swapped between ND10, ND70, ND80, or any other designation. The anti-rotation plate tab must align with the hub indent or the lock drifts. The latch slide clip must be engaged at center or the latch misaligns. For keyed IC functions, the timing guide must be consulted before cylinder installation. Sourcing correct cylindrical locks parts and diagrams starts with the function designation, then the cylinder type, then the door thickness, and then the finish code. Security Parts stocks every ND Series component with same-day shipping and pre-order support at 845-935-0301.

FAQs

What are the ten components in the Schlage ND Series exploded view diagram? 

Adjustment Plate, Outside Lever, Chassis, Latch, Strike, Anti-Rotation Plate, Optional Spacer (for non-standard door thickness), Mounting Screws, Inside Lever, Rose, and Inside Spring Cage.

What door thickness does the Schlage ND Series support?

 1-3/8 inch to 2-1/8 inch. Standard installation is 1-3/4 inch with no spacers required. Spacers are provided for 1-3/8 inch doors. The adjustment plate repositions for 1-5/8, 2, and 2-1/8 inch doors.

Why is the "timing guide" important for some ND Series functions?

 Certain ND Series lock functions require internal components to be set to a specific position before the lock operates correctly. The ND Series Timing Guide (P517-432) must be followed before cylinder installation on these functions, or the lock will not operate after assembly.

What is the default Schlage ND Series backset?

 2-3/4 inches standard. 2-3/8 inch short backset is available. A 43-005 extension provides a 5-inch backset for applications where the standard dimensions do not reach the door edge.

What does the RX option add to a Schlage ND Series lock?

 A micro-switch inside the chassis monitors lever rotation and signals the use of the opening to the access control system. Available on ND10, ND12, ND80, ND81, and ND96 functions.