Micro Coaxial Cable factory

How to Properly Strain Relief Micro Coaxial Cable Connections

Micro coaxial cables power critical connections in electronics – from tiny medical devices to high-speed camera sensors and aerospace systems. Their small size and delicate inner conductor make them vulnerable. Without proper ​strain relief, bending, pulling, or vibration can sever the connection, causing costly failures. Here’s how to protect them effectively:

Why Strain Relief Matters

Micro coax cables (like MHF/U.FL or SMPM types) handle signals for antennas, displays, and sensors. Strain near connectors:

• ​Causes intermittent signals or complete failure
• ​Damages solder joints at the connector/cable interface
• ​Frays shielding, leading to noise interference

Preventing this extends cable life and ensures reliability in critical applications.

Essential Methods for Strain Relief

1. ​Adhesive Reinforcement (Most Common)

• ​Materials Needed: Electronic-grade adhesive (e.g., epoxy, specialized cable glue), strain relief boot/clamp (optional)
• ​Steps:
  1. ​Prepare the joint: Clean the cable-connector junction with isopropyl alcohol.
  2. ​Apply adhesive: Use a toothpick or syringe to dab epoxy onto the cable entry point of the connector. Avoid covering vents or pins.
  3. ​Form a strain relief “bead”​: Extend the epoxy 2-5mm along the cable jacket to create a flexible bond.
  4. ​Add a boot (optional): Slip a silicone boot over the joint before gluing for extra support.
  5. ​Cure: Let sit undisturbed per adhesive instructions (usually 24 hours).

2. ​Mechanical Clamping

• ​Best For: Repetitive motion or industrial vibration.
• ​Tools: Zip ties, heat-shrink tubing with adhesive liner, or PCB-mounted cable clamps.
• ​Steps:
  1. ​Secure near the connector: Use a small zip tie to anchor the cable to a fixed point (e.g., PCB hole, chassis slot). ​Don’t overtighten – this crimps the cable.
  2. ​Add adhesive heat-shrink: Slide a length of adhesive-lined heat-shrink over the cable and connector base. Heat with a heat gun to seal.

3. ​Routing & Securing Techniques

• ​Use cable guides: Affix cables with clips or sticky pads 3-5cm from connectors.
• ​Avoid sharp bends: Keep bend radius > 10x the cable diameter.
• ​Prevent tension: Leave slack to absorb movement.

Critical Mistakes to Avoid

• ​Ignoring cable direction: Never bend sharply within 5mm of the connector.
• ​Over-applying adhesive: Too much glue makes joints brittle.
• ​Skipping cleaning: Oils or residue weaken adhesive bonds.
• ​Pulling cables during assembly: Hold connectors – not cables – when plugging/unplugging.

Tools & Materials Checklist

Key Takeaway

Proper strain relief isn’t optional for micro coax – it’s essential for signal integrity and device reliability. Use adhesives for small devices, mechanical clamps for high-vibration environments, and always secure cables with care. Invest in quality materials and careful routing to prevent failures that can halt entire systems.