What are the strip layers for coaxial cable?

Coaxial cable strip involves exposing multiple layers in sequence: (1) Jacket strip: remove the outer PVC, PE, or FEP jacket to expose the shield. Length varies by connector: N-type crimp typically 15-20mm. (2) Shield preparation: for braided shield: fold the braid back over the jacket (for clamp connectors) or trim it (for crimp connectors). For foil shield: remove the foil. For combination foil+braid: remove foil, fold braid. (3) Dielectric strip: remove the dielectric (PTFE, PE, foam) to expose the center conductor. Length: typically 3-6mm, must be precise to ±0.5mm for proper pin depth in the connector. (4) Center conductor: may need to be trimmed to length. For solder-pin connectors: tin the conductor. For crimp connectors: clean and straight. All dimensions are specified in the connector manufacturer's installation guide. Using the wrong dimensions results in poor return loss, incorrect impedance at the connector transition, and unreliable mechanical contact.

What tools are used for cable stripping?

Rotary stripper: the standard tool for field and production use. Adjustable blade depth and stop length. Cable-specific versions available for each cable type (RG-58, RG-213, LMR-400, etc.). Brands: Ripley, Ideal, Jonard. Advantage: consistent, repeatable results. Coax prep tool: combination tool that strips all three layers (jacket, dielectric, center conductor) in one step. Cable-specific. Used in CATV installation. Razor blade: for semi-rigid cable (SMA 0.141, 0.085) and precision work. Requires skill. Score and break the outer conductor, then remove the dielectric with a clean cut. Thermal stripper: for PTFE dielectric cables. PTFE does not cut cleanly with a blade. Thermal strippers melt through the PTFE at a controlled temperature (350-400°C). Essential for PTFE-insulated cables like RG-316, RG-400. Automatic strippers: for production volume. Programmable strip lengths, wire gauges, and layer sequences. CNC-controlled blade depth.

What are common stripping mistakes?

(1) Nicking the center conductor: a blade cut into the center conductor creates a stress riser that can cause fatigue failure, especially with flex cables. Even a 10% depth nick reduces the tensile strength significantly. The nick also creates an impedance discontinuity at the cut point. (2) Wrong strip length: too long: center conductor protrudes too far, pin depth incorrect, impedance mismatch at the transition. Too short: conductor does not reach the connector contact, intermittent or open connection. (3) Damaged dielectric: cutting into the dielectric during jacket strip changes the impedance at the stripped section. Foam dielectric is especially fragile. Use the correct blade depth setting. (4) Loose braid strands: stray braid wires can short to the center conductor inside the connector, causing a dead short or intermittent contact. Always trim all loose strands and inspect before connector assembly. (5) Wrong blade depth: cutting too deep on the jacket strip cuts through the shield. This is the most common mistake with rotary strippers when switching cable types.

Cable Assembly

Cable Stripping

/kay-bul strip-ping/

Precision removal: jacket (15-20mm), shield (fold/trim braid), dielectric (3-6mm ±0.5mm), center conductor (trim/tin). Tools: rotary stripper (Ripley, Ideal), thermal stripper (PTFE, 350-400°C), razor (semi-rigid), auto (production). Critical: correct blade depth, no nicks, clean braid, manufacturer dimensions ±0.5mm.

Dielectric: 3-6mm

Tolerance: ±0.5mm

PTFE: Thermal strip

Understanding Cable Stripping

Cable stripping is the most skill-dependent step in RF cable assembly. Get the dimensions wrong by a millimeter and the connector's impedance transitions are compromised, showing up as degraded return loss on a sweep test. Nick the center conductor and the cable will fail under vibration. Leave a stray braid strand and create an intermittent short. Proper stripping requires the right tools, the right dimensions, and a careful hand.

Strip Dimension Importance

Cable Stripping:
Precision removal: jacket (15-20mm), shield (fold/trim braid), dielectric (3-6mm ±0.5mm), center conductor (trim/tin). Tools: rotary stripper (Ripley, Ideal), thermal stripper (PTFE, 350-400°C), razor (semi-rigid), auto...

Key specifications:
-20 mm | -6 mm | 0.5 mm

Power: P(dBm) = 10log(P_mW), 0dBm = 1mW

Stripping Tool Comparison

Tool	Cable Type	Precision	Speed	Application
Rotary stripper	Flexible coax	High	Fast	Field/production
Thermal stripper	PTFE dielectric	Very high	Medium	RG-316, RG-400
Razor blade	Semi-rigid	Operator dep.	Slow	Lab, precision
Coax prep tool	CATV (RG-6/11)	Medium	Very fast	CATV install
CNC auto	Any	Highest	Fastest	Production vol.

Key Equations

Decibel conversion:
Power: dB = 10log(P₂/P₁)
Voltage: dB = 20log(V₂/V₁)

dBm to watts:
P(W) = 10^{(dBm−30)/10}
0 dBm = 1 mW, +30 dBm = 1 W

Wavelength:
λ = c/f = 300/f(MHz) meters

Comparison

Connector	Freq Max	Impedance	Power	Interface
SMA	18 GHz	50 Ω	0.5 W	Threaded
N-Type	11 GHz	50 Ω	5 W	Threaded
2.92mm (K)	40 GHz	50 Ω	0.3 W	Threaded
1.85mm (V)	67 GHz	50 Ω	0.2 W	Threaded
1.0mm (W)	110 GHz	50 Ω	0.1 W	Threaded

Common Questions

Frequently Asked Questions

Layers?

Jacket (15-20mm), shield (fold or trim braid, remove foil), dielectric (3-6mm, ±0.5mm), center conductor (trim/tin). All dimensions from connector manufacturer installation guide. Wrong dimensions = poor RL and mechanical failure.

Tools?

Rotary (Ripley/Ideal, field standard), thermal (PTFE, 350-400°C), razor (semi-rigid), coax prep (CATV), CNC auto (production). Match tool to cable type. Adjust blade depth per cable OD.

Mistakes?

Center conductor nick (fatigue failure), wrong length (impedance mismatch), damaged dielectric (foam fragile), loose braid strands (shorts), wrong blade depth (cuts shield). Inspect before assembly.

Related Terms

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