How to Use the Multi-Cable Stripping Tool
Cable Preparation and Connector Installation Instructions
The PLNST-7020, (Multi-Cable Stripping Tool), is a specially designed cable preparation tool for Gamma Electronics 1/2″ air core coax cable. This tool will trim the cable to proper conductor and jacket preparation lengths for Gamma Electronics certified connectors.
These instructions on how to utilize the Multi-Cable Stripping Tool have been broken into 3 parts:
1 – Cutting the Cable
2 – Stripping the Cable with the Multi-Cable Stripping Tool
3 – Attaching the Connector to the Stripped Cable
These instructions utilize the equipment listed in the equipment section below.
- 1 (one) Gamma plenum connector (NM-50PLN, NF-50PLN, 4310M-50PLN, 4310F-50PLM)
- 1 (one) ½” coaxial cable (Andrew HL4PV-50 or AL4RPV-50, RFS ICA12-50JPL, Gamma PLN-(CU, AL)-50, STF50-LSZH-1/2, or Commscope LDF4-50A)
- 1 (one) cable cutting tool (Gamma cutters, hacksaw, or bandsaw)
- 1 (one) Gamma plenum cable stripping tool (P/N: PLNST-7020) with three bushings and Allen keys
- 1 (one) pair of small diagonal wire cutters
- 1 (one) tube cutter (optional)
- Razor blade or utility knife
Part 1 – Cutting the Cable
The most critical step to successful connector installation is a proper cut of the cable which has four characteristics, (listed below). The vast majority of installation failures are caused by an improper cut.
1. Cut the Cable in a “Valley” of the Shield Corrugation
This is shown in Figure 1. The “valley” refers to a lower point in the shield corrugation. This step is critical because the Multi-Cable Stripping Tool is designed to stop cutting the cable shield when the center conductor hits the “stop” inside of the stripping tool. When the cut is done correctly, it also results in the proper “flair” on the final shield cut.
2. The Cut is Square from a Side View
This means the cut surface is as close to a 90° from the length, as shown in Figure 2. This is usually not a problem when using Gamma cutters or a bandsaw, but can be a problem in the case of a hacksaw where the blade may wander. It is important to securely mount the cable while cutting and only use sharp blades.
3. The Cut is Round When Viewing the Cut from an End View
If you look straight into the end of the cable, the cut in the cable shield should look almost like a perfect circle, as shown in Figure 3. On occasion, some cutting tools can crush or deform the cable during cutting, especially if the blades are dull. A proper cut can be achieved by rotating the cut while gently applying pressure, and using sharp blades. In these scenarios, a tube cutter can prove very effective, especially when working with aluminum shielded cables.
4. The Center Conductor is Centered within the Cable
The cause of this is similar to #3 above. When the center conductor is out-of-center, it will wander off-axis during the stripping procedure.
Part 2 – Stripping the Cable with the Multi-Cable Stripping Tool
1. Select the Appropriate Bushing
Select the Appropriate Bushing from the “Cable Applicable Bushings” table below. The bushing in the Gamma stripping tool can be changed out by loosening screw A in Figure 4 below. The bushing keeps the cable centered inside the stripping tool.
Cable Applicable Bushings
Cable Brand (Type, Shield Material)
RFS (Plenum, Copper)
Commscope (Plenum, Copper)
Commscope (Plenum, Aluminum)
Gamma (Plenum, Copper)
Gamma (Plenum, Aluminum)
Gamma (Annular, Copper)
Commscope (Annular, Copper)
2. Select the Appropriate Mounting Atachment
The stripping tool can be operated by hand, (or manual mode), with use of the “T-Handle”, or it can be inserted into a drill. In the case of manual mode, the T-handle needs to be attached by using set screw “B” in Figure 5, which can be loosened or tightened with the help of one of the included allen wrenches. In the case of drill mode, the T-handle needs to be removed so that the mandrel can be inserted into the drill as shown in Figure 5.
3. Hold the Cable Firmly and Insert it into the Multi-Cable Stripping Tool
Hold the cable firmly and insert it into the Multi-Cable Stripping Tool, up to the jacket stripping blade.
4. Rotate the Tool Clockwise at a Slow RPM
Rotate the tool clockwise at a slow RPM, applying gentle forward pressure.
5. Rotate Until the Center Conductor Reaches the Tool’s Internal “Stop”
When the center conductor reaches the internal “Stop” the cable strip is complete.
6. Stop the Rotation and Extract the Cable
Stop the rotation and extract the cable. A properly stripped cable is shown in Figure 6.
7. (Optional) Re-position the Cable’s Internal Dielectric
(Optional) Re-position the cable’s internal dielectric by inserting the stripped cable into the recess, (C), in the back of the tool as shown in Figure 7. This step is not usually necessary.
8. Remove/Clean Up Excessive Dielectric Spacer Material
If there is excessive dielectric spacer material protruding out the end of the cut cable, a pair of small diagonal cutters can be used to remove it as shown in Figure 8. Remnants of cable outer sheath rubber can be removed with a razor blade or utility knife.
9. Check that the Cable is Cut & Stripped Properly
The properly stripped cable should feature a center conductor that is flat and square on the end with a beveled (chamfered) rim. There should be a shield corrugation “valley” immediately in front of the stripped sheath edge. See Figure 9 below.
Part 3 – Attaching the Connector to the Stripped Cable
1. Install O-Ring
Remove the silicone o-ring from the connector package and slide it over the end of the cable and into the corrugation “valley” immediately in front of the stripped outer sheath as shown in Figure 10.
2. Install Bottom Half of Connector
Separate the two halves of the connector and slide the bottom half over the end of the cable with the threads toward cable end. Pull, (while twisting), as far as possible away from the end of the cable until the teeth lock into the first valley (from the end) of the shield corrugation. The end of the connector should be flush with the edge of the shield as shown in Figure 11.
3. Install Upper Half of Connector
Slide the upper half of the connector over the cable center conductor and engage the threads. Hand-tighten the two halves of the connector and use a torque wrench to tighten the two halves of the connector to a target torque of 18 Newton-meters (160 inch-lbs) as shown in Figure 12.
4. Installation is Complete
The RF Compression Connector installation is now complete.