Asymmetric Knob Turn Cylinders: Extended Shank Turnpieces for Recessed Frames
Engineering Overview: Installation guide for extended-shank thumbturn Euro cylinders, clearing deep architectural door trims and recessed security screens.
Technical & Engineering Specifications
| Material | Solid H59 Brass with Reinforced Internal Stem |
|---|---|
| Application | Rebated Timber Doors with Deep Decorative Mouldings |
| Cylinder Standard | Euro Profile DIN 18252 |
| Turnpiece Extension | 15 mm, 25 mm, 35 mm Extended Shank Necks |
Overcoming Recessed Door Trim Clearance
On thick rebated timber doors and doors with heavy decorative mouldings, standard thumbturn knobs sit recessed inside the handle plate, making operation difficult.
Extended Shank Engineering
- Long-Shank Stems: Features an extended solid brass neck (15 mm to 35 mm extension) connecting the cylinder plug to the thumbturn knob.
- Torsional Strength: Machined from solid brass with high-tensile retaining pins, preventing stem twisting under heavy manual torque.
- Seamless Sizing: Available across asymmetrical modular lengths up to 130 mm.
Frequently Asked Engineering & Selection Questions
Q1: Why are long-shank thumbturn cylinders specified?
They extend the turn knob past deep decorative door mouldings or handle plates so occupants can grip and turn the knob comfortably.