Recommended Guidelines for Design & Dimensioning of Semi-Rigid Cable Assemblies.

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Semi-Rigid Cable Assemblies.

Semi-Rigid Cable Assemblies Design Guidelines.

Coaxicom has been manufacturing semi-rigid cable assemblies since 1984. We have developed a number of guidelines for the design and dimensioning of cable assemblies that will provide the user with assemblies that are cost-effective, perform well, and are reliable.

We incorporate Coaxicom connectors, or those specified by the user. Some of these guidelines are summarized here, and illustrated below.

For information on cables described or other products from Coaxicom’s broad line of connectors, adapters, terminations, attenuators, phase adjusters, and cable assemblies, contact our Coaxicom Team at 866. Coaxicom (262.9426) or via email to

  1. Make drawings full scale.
  2. Use tight dimensioning, but loose tolerances. Tolerances of +/-0.030″ are generally recommended. Cables (except very short ones) are slightly flexible, and can be “walked” into next higher assembly.
  3. Dimension lengths as follows: (a) Straight plugs and jacks: To the reference plane. (b) Bulkhead jacks: To the bulkhead mounting surface. (c) Right angle connectors: To the centerline of the mating surface.
  4. Avoid right angle connectors whenever possible. They are more expensive than straight connectors and perform poorly at high frequencies. Coaxicom can bend cables tightly enough so that a straight plug will have the same profile as a right angle connector.
  5. Avoid bulkhead and panel mounted connectors if possible, to preclude the need for expensive tooling to ensure correct connector orientation.
  6. Dimension straight lengths to the start of bends. A radius to the inside of the cable, and associated angle should be used to specify bends. Radii to the center- line of cables are not measurable. Dimensions that cannot be measured should be avoided.
  7. Design bend radius as large as possible, and make them identical if you can. Minimize the number of cable bends wherever possible. Design cable paths for utility, not appearance. Use gradual S bends, rather than straight runs followed by 90 degree bends.
  8. Use stress relief loops whenever possible on short cable assemblies.
  9. Avoid direct marking. Use hot-stamped, heat shrink tube.

For more tips and advice, visit Coaxicom Engineering, or email us at, or start by using Coaxicom cable assembler builder. For a quick reference product sheet, complete the info below and access an instant download. 

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