Board Spacers, Standoffs

Part Number	Description / PDF	Quantity
NAS42DD6-32A RAF	ALUMINUM UNTHREADED SPACER 3/8 R	0
M2200-4007-B RAF	8MM HEX X 25MM X M4 THD	388
1537-A-6-SS-20 RAF	1/4 RD X 1/2 X .140 ID	500
NAS1831A4C60 RAF	ALUMINUM 1/4 HEX FEMALE STANDOFF	245
1634-256-SS RAF	3/16 RD X 5/16 LENGTH	396
1952-3716-S RAF	5/8 RD X 1/2 LENGTH	500
1696-1032-S-12 RAF	1/4 RD X 1-1/4 LENGTH	300
M1262-2545-SS RAF	HEX STANDOFF M2.5X0.45 SS 15MM	181
1186-12-SS RAF	3/8 RD X 1/4 X .218 ID	500
3609-B-440-B RAF	3/8_HEX_SWAGE_STANDOFFS	1291
4534-632-B RAF	1/4 HEX X 1/2 LENGTH	3512
4546-632-B-12 RAF	1/4 HEX X 1-1/4 LENGTH	459
M2142-3005-SS RAF	HEX STANDOFF M3X0.5 SS 7MM	925
M2101-3005-B-12 RAF	4.5MM HEX X 6MM X M3 THD	8595
1681-832-SS RAF	1/4 RD X 5/16 LENGTH	257
M0533-4-N RAF	ROUND SPACER NYLON 4MM	373
M2155-3005-S-12 RAF	6MM HEX X 20MM X M3 THD	500
1142-6-N RAF	1/4 RD X 1 3/8 X .140 ID	500
4573-1032-AL RAF	5/16 HEX X 3/8 LENGTH	80
4532-440-SS RAF	HEX STANDOFF #4-40 SS 3/8"	1374

Board Spacers, Standoffs

1. Overview

Board spacers and standoffs are specialized hardware components used to create controlled spacing between printed circuit boards (PCBs), panels, or structural elements. They provide mechanical support, electrical isolation, and thermal management in electronic assemblies. Their importance in modern technology includes enabling compact designs, reducing vibration stress, and improving heat dissipation in devices ranging from smartphones to industrial control systems.

2. Main Types & Functional Classification

Type	Functional Features	Application Examples
Cylindrical Spacers	Simple tubular design with uniform diameter	PCB layer separation in consumer electronics
Hexagonal Standoffs	6-sided structure for wrench tightening	Industrial equipment panel mounting
Self-clinching Standoffs	Permanent installation with threaded compression	Sheet metal enclosures in servers
Adjustable Spacers	Variable length through threaded adjustment	Prototype development and testing
Insulated Spacers	Non-conductive materials for electrical isolation	High-voltage power supply assemblies

3. Structure & Composition

Typical construction includes:

Material: Stainless steel (corrosion resistance), aluminum (lightweight), or nylon (insulation)
Geometry: Cylindrical (standard), stepped (for multiple board heights), or flanged (for load distribution)
Installation Features: Internal threading (male/female), knurled surfaces (for grip), or press-fit tabs
Surface Treatment: Passivation (metal), UV resistance (plastics), or EMI shielding coating

4. Key Technical Specifications

Parameter	Importance
Material Hardness (HV)	Determines wear resistance and load capacity
Thread Engagement Length	Affects vibration resistance in dynamic environments
Thermal Conductivity (W/m K)	Critical for heat dissipation in power electronics
Dielectric Strength (kV/mm)	Safety factor in high-voltage applications
Installation Torque Rating	Prevents over-tightening damage to PCBs

5. Application Fields

Primary industries include:

Electronics Manufacturing: Server racks, LED displays
Automotive: Engine control units (ECUs), ADAS systems
Aerospace: Satellite PCB mounting, avionics enclosures
Medical Devices: MRI scanner internal structures
Consumer Electronics: Smartphone PCB stacking

6. Leading Manufacturers & Products

Manufacturer	Representative Product
PEM	S-8900 Series self-clinching standoffs
RS Components	486-8826 insulated hexagonal spacers
Mouser Electronics	925206-12 adjustable PCB spacers
McMaster-Carr	91285A102 stainless steel standoffs

7. Selection Recommendations

Evaluate mechanical load requirements vs material strength
Match thread type (UNC/UNF/Metric) with assembly hardware
Consider CTE (Coefficient of Thermal Expansion) compatibility with PCB materials
Select insulated variants for >50V circuits
Use vibration-damping coatings in mobile applications

8. Industry Trends

Emerging developments include:

Miniaturization: Sub-1mm spacers for wearable devices
Material Innovation: Conductive polymer composites for EMI shielding
Smart Integration: Standoffs with embedded strain gauges for structural monitoring
Automated Installation: Self-aligning designs for robotic assembly lines
Sustainability: Biodegradable plastic options (PLA-based) entering mainstream production