Board Spacers, Standoffs

Part Number	Description / PDF	Quantity
1247-38-SS-20 RAF	5/8 RD X 3/16 X .380 ID	20
4504T-440-S-12 RAF	3/16 HEX X 15/32 LENGTH	1030
2104-632-SS-20 RAF	1/4 HEX X 1/2 LENGTH	228
4500A-440-AL RAF	3/16 HEX X 5/32 LENGTH	256
M1381-4007-SS RAF	8MM HEX X 52MM X M4 THD	92
2107-632-AL RAF	HEX STANDOFF #6-32 ALUM 11/16"	752
NAS1829AC4E11 RAF	ALUMINUM 1/4 HEX MALE/FEMALE STA	250
4502-256-B RAF	3/16 HEX X 5/16 LENGTH	398
1194-8-S-12 RAF	3/8 RD X 3/4 X .166 ID	500
1148-4-N RAF	1/4 RD X 1 3/4 X .115 ID	290
M1457-6010-B RAF	13MM HEX X 10MM X M6 THD	499
1248-31-AL RAF	5/8 RD X 1/4 X .315 ID	318
M1123-5008-S-12 RAF	8MM RD X 28MM X M5 THD	1413
1217-25-B-12 RAF	1/2 RD X 1/4 X .252 ID	400
4560-440-S-12 RAF	1/4 HEX X 2-1/4 LENGTH	300
4568-440-AL RAF	1/4 HEX X 3-1/2 LENGTH	48
4501-440-B-5 RAF	HEX STANDOFF #4-40 BRASS 1/4"	0
4546-632-SS RAF	HEX STANDOFF #6-32 SS 1-1/4"	946
2112-832-N RAF	1/4 HEX X 1.00 LENGTH	200
2056T-256-AL RAF	HEX STANDOFF #2-56 ALUM 11.9MM	907

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