M3.5 x 15.9mm Torx / Slotted Combination Press-In Captive Panel Screws (47-92-261-21) - Steel Ferrule / Smooth Knob Description
The M3.5 x 15.9mm Torx / Slotted Combination Press-In Captive Panel Screws (47-92-261-21) - Steel Ferrule / Smooth Knob has the following features:
- Drive Size: T15
- Drive Type: Torx / Slotted Combination
- Fastened Head Height (H2): 11.2 mm
- Zinc Plated / Smooth / Zinc Plated Finish
- Screw / Knob / Ferrule Finish Classification
- Head Diameter (D): 11.5 mm
- Installation Style: Press-In
- Steel / Aluminium / Steel
- Screw / Knob / Ferrule Material Classification
- Steel / Aluminium / Steel Material Family
- Maximum Screw Protrusion (P2): 8.5 mm
- Minimum Screw Protrusion (P1): 3.7 mm
- Panel Thickness (Min) (A): 0.9 mm
- Promoted: New Product
- Shaft Diameter (SD): 6.3 mm
- Thread Size: M3.5 (3.5 mm)
- Total Float Value: 0.8 mm
- Unfastened Head Height (H1): 15.9 mm
Discover more about the Metric Torx Knob Captive Panel Screws range.
Metric Torx knob captive panel screws are precision-engineered fasteners built for applications requiring frequent panel removal without the risk of losing components. Each assembly integrates a spring-loaded screw within a ferrule, paired with a durable knob featuring either a Torx or dual-function Torx / slotted drive.
Once secured, these captive fasteners remain permanently retained in the panel, ensuring operational efficiency, repeatable performance and quick accessibility, even during intensive maintenance cycles.
Widely used across sectors including electronics, manufacturing and mechanical engineering, they are an ideal solution for access panels, control housings and service units where durability and ease of use are paramount.
How Metric Torx and Torx / Slotted Combi Knob Captive Panel Screws Work
These captive fasteners operate through three coordinated elements: a ferrule, a spring-loaded screw, and a knob with an integrated Torx or Torx / slotted drive.
During installation, the ferrule is fitted into a pilot hole within the outer panel. The captive screw is then held securely within the ferrule by a spring mechanism. When torque is applied via the knob, the spring compresses, extending the screw threads ready to engage with the mating component.
The Torx drive offers superior torque transfer and reduced cam-out compared to traditional slotted designs, while the Torx / slotted combi drive provides added flexibility, allowing operators to use either a Torx driver or a flat-blade screwdriver depending on accessibility.
For instance, in a control panel assembly, an engineer can quickly loosen a Torx knob captive screw using a handheld driver for precision, or a flat-blade screwdriver in tight access conditions, all while ensuring the screw remains permanently attached to the panel.
Materials Metric Torx Knob Captive Panel Screws Are Made From
Due to their complex, multi-part design, these screws are produced using a combination of premium metals, each selected for its functional strengths:
- Steel: Offers robust mechanical strength and load-bearing capacity for high-torque applications.
- Aluminium: Lightweight and resistant to corrosion, ideal for assemblies where reduced mass is key.
- Stainless Steel: Provides lasting corrosion protection and exceptional wear resistance, ensuring reliability in repetitive scenarios..
Because each component (the ferrule, spring, and knob) serves a distinct mechanical purpose, the material composition varies across parts. Selection should therefore focus on application and installation type rather than a single material specification.
Sizes and Types of Metric Torx Knob Captive Panel Screws Available
Accu’s range of Metric Torx and Torx / slotted combi knob captive panel screws is available in M3 (3mm) to M6 (6mm) thread sizes, accommodating a variety of panel thicknesses and configurations.
Installation types include:
- Flare In: Suitable for near-edge installation in plastics, castings and other non-metal substrates.
- Floating: Allows for controlled radial movement to compensate for moderate misalignment.
PC Board: Designed specifically for PCBs and fibreglass panels.
- Press In: Delivers a flush fit within sheet metal for a clean aesthetic.
- Snap In: Enables quick, tool-free installation for rapid assembly lines.
Each configuration features either a Torx drive for precise, slip-resistant engagement or a Torx / slotted combi drive for multi-tool compatibility. Screw protrusion lengths range from 3.8mm to 12.6mm when fully depressed, providing flexibility across different panel designs.
FAQs
Q: What are the advantages of using a Torx drive on captive panel screws?
A: Torx drives offer greater torque transmission and reduced wear compared to slotted drives. They minimise the risk of slippage and tool damage, making them ideal for repeated use and controlled assembly operations.
Q: What is the benefit of a Torx / Slotted Combi drive?
A: The combination drive provides versatility. It can be driven using either a Torx bit or a standard flat-blade screwdriver. This flexibility is particularly valuable in maintenance environments where tool access may vary.
Q: Can Torx knob captive panel screws be used with power tools?
A: No. The chance of over-torqueing is heightened with power tools and should be avoided to protect the ferrule and internal spring assembly.
Q: Are Torx and Torx / Slotted Combi knob captive screws compatible with PCBs and fibreglass panels?
A: Absolutely. PC Board variants are specifically engineered for use with composites like printed circuit boards and fibreglass, offering a secure and non-damaging fit.
