When we review a custom RF cable assembly for production, we do not choose crimp or solder by habit. We first check the cable group, connector structure, center contact design, ferrule fit, order quantity, routing condition, and test requirement. For most flexible coaxial cable assemblies, crimp termination is easier to control in batch production. Solder termination is still useful for prototypes, semi rigid cable, solder cup contacts, and special connector structures.
What We Check First
The first check is cable fit. The cable outer diameter, dielectric diameter, center conductor, shield structure, and jacket thickness decide whether a connector version can be used. A ferrule that fits RG174 may not fit RG58. A center contact designed for one conductor size may not hold another conductor correctly.
The second check is connector construction. Some RF connectors are made for crimp termination. Some are made for solder termination. Some use a mixed process, such as soldered center contact and crimped outer ferrule. If the drawing defines the process, we follow the structure instead of changing it for convenience.
The third check is production quantity. For a small sample order, solder may be acceptable when the connector structure allows it. For repeated production, crimp is often easier to standardize because the tool, die cavity, strip length, ferrule position, and inspection method can be fixed.
Why Crimp Often Wins
For flexible coaxial cable assemblies, crimp termination gives us better production control. Once the connector, cable, ferrule, strip length, and crimp die are confirmed, the process can be repeated with stable tooling. This matters for antenna cables, wireless module cables, cabinet jumpers, panel pigtails, and other custom RF cable assemblies that need consistent output.
Crimping also makes inspection clearer. We can check whether the ferrule is fully seated, whether the braid is prepared correctly, whether the jacket reaches the proper support point, and whether the crimp shape is consistent. Pull test, visual inspection, continuity test, and RF test data can be used together to judge the build.
A crimp process is not reliable just because it is fast. It becomes reliable when the connector version matches the cable group, the die cavity matches the ferrule, and the first article sample confirms both mechanical retention and RF performance.
When We Keep Solder
Solder is still the right process for many RF builds. We keep solder termination when the connector is designed with a solder cup, when the center contact requires soldering, when the cable is semi rigid or semi flexible, or when a prototype needs a structure that is not suitable for crimp tooling.
Solder can also make sense for a small quantity order. If a customer needs a few test samples with a special connector, preparing a dedicated crimp setup may not be practical. In that case, solder can be used if the connector drawing, cable structure, and inspection standard support it.
The control point is heat. Too much heat can affect the dielectric near the connector end. Too much solder can change the shape of the contact area. Poor wetting can create unstable contact. Solder wicking can make the cable end stiff and weak during bending. These issues need to be checked before the sample is approved for production.
Mixed Termination Is Common
Some RF connectors are not pure crimp or pure solder. A common structure is a soldered center contact with a crimped outer ferrule. The center conductor is fixed by solder, while the braid and jacket area are held by the ferrule. This structure can be useful when the center contact needs soldering but the outer shield still needs stable mechanical retention.
For these connectors, the product name does not tell the whole story. The same RF cable assembly may include soldering, crimping, heat shrink, boot support, and final RF testing. If a customer asks whether the connector is crimp or solder, the answer may be that both processes are used at different points of the same connector end.
When We Recommend Crimp
We usually recommend crimp termination when the order uses flexible coaxial cable and the connector has a proven crimp version for that cable group. This applies to many SMA, BNC, TNC, N Type, MCX, MMCX, SMB, FAKRA, and similar cable assemblies.
Crimp is also a better fit when the customer needs repeated production, stable delivery, clear inspection records, and lower process variation. If the cable will be bent during installation or used in equipment with vibration, the crimp area and strain relief can be reviewed together during sample approval.
When We Recommend Solder
We recommend solder termination when the connector construction requires it or when the cable type makes crimping unsuitable. Semi rigid cable, semi flexible cable, solder cup connectors, selected PCB transitions, and special center contact designs often fall into this group.
Solder can also be the right choice for early samples when the project is still changing. If the customer has not fixed the cable length, connector direction, panel position, or internal routing, solder may help build evaluation samples before the final production structure is confirmed.
For soldered RF connectors, we pay close attention to the finished cable end. The contact has to stay centered. The dielectric must not be damaged by heat. The solder should not flow too far into the cable. The joint has to remain stable after bending, handling, and mating.
FAQ
Conclusion
Crimp and solder RF connectors both have a place in production. For flexible coaxial cable assemblies, crimp is usually easier to control across batches because tooling, ferrule position, strip length, inspection, and pull test can be standardized. Solder remains suitable for prototypes, semi rigid cable, solder cup connectors, selected center contacts, and special RF structures. When we review a custom RF cable assembly, we choose the termination process by cable fit, connector design, production quantity, mechanical load, and RF test requirement.