6.4 Component Lead Cutting and Lifting

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Printed Board Type: R/F/W/C
Skill Level: Advanced
Conformance Level: Medium
Revision: Pending
Revision Date: Pending

OUTLINE

Figure 1: Component Lead Cutting

This procedure covers the general guidelines for modifications that involve cutting and lifting component leads. Leads may be permanently cut or lifted due to engineering changes, or reconnected if done for testing purposes.

PROCEDURE REFERENCE
2.1	Handling Electronic Assemblies
2.2.1	Cleaning, Local
6.1	Jumper Wires

TOOLS & MATERIALS
Cleaner

Figure 2: Specially designed cutters used to cut component leads.

Cleaning Wipes
Cutters
Flux
Microscope System
Pick
Soldering Iron with Tips
Solder
Wood Stick

NOTE
Specially designed cutters are required when cutting component leads. 

PROCEDURE - Lead Cutting, Plated Through Hole Components

1. Figure 3: Place the cutter at the mid point in the lead and snip through to cut the lead.

   Select the component lead that needs to be cut and place the cutter in position. (See Figure 3). Place the cutter at the mid point in the lead and snip through to cut the lead.
   
   
2. To ensure that the lead has been severed, the upper portion of the lead may be slightly lifted using a pick. Visually inspect, or electrically test, to ensure that the lead has been severed.
   
   
3. If the lead needs to be reconnected, gently push the upper portion of the severed lead down until it touches the lower portion of the severed lead.
   
   
4. Solder both halves of the severed lead together. (See Figure 5).
   
   NOTE
   The lower portion of the lead may move during soldering since it is not anchored in position.
   
   
5. If required, clean the flux residue and inspect.

Figure 5: If needed, solder both halves of the severed lead together.

Figure 4: To ensure that the lead has been severed, the upper portion of the lead may be slightly lifted using a pick.

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PROCEDURE - Lead Cutting, J Lead Components

1. Figure 6: Place the cutter at the mid point in the lead and snip through to cut the lead.

   Select the component lead that needs to be cut and place the cutter in position. (See Figure 6). Place the cutter at the mid point in the lead and snip through to cut the lead.
   
   
2. To ensure that the lead has been severed, the upper portion of the lead may be slightly lifted using a pick. (See Figure 7). Visually inspect, or electrically test, to ensure that the lead has been severed.
   
   
3. If the lead needs to be reconnected, gently push the upper portion of the severed lead down until it touches the lower portion of the severed lead.
   
   
4. Solder both halves of the severed lead together. (See Figure 8).
   
   NOTE
   The lower portion of the lead may move during soldering since it is not anchored in position.
   
   
5. If required, clean the flux residue and inspect.

Figure 8: If needed, solder both halves of the severed lead together.

Figure 7: To ensure that the lead has been severed, the upper portion of the lead may be slightly lifted using a pick.

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PROCEDURE - Lead Lifting, Standard Gull Wing Components

1. Figure 9: Gently place a pick behind the component lead to be lifted. Apply a soldering iron tip to the foot of the component lead. Apply slight force with the pick to lift the lead as the soldering iron reflows the joint.

   Select the component lead that needs to be lifted. Apply a soldering iron and solder braid to remove the excess solder from the joint.
   
   
2. Gently place a pick behind the component lead to be lifted. Apply a soldering iron tip to the foot of the component lead. Apply slight force with the pick to lift the lead as the soldering iron reflows the joint. (See Figure 9).
   
   
3. Visually inspect, or electrically test, to ensure that the lead has been lifted. See (Figure 10).
   
   
4. If the lead needs to be reconnected, gently push the lead down until it touches the pad and solder.
   
   
5. If required, clean the flux residue and inspect.

Figure 10: Visually inspect, or electrically test, to ensure that the lead has been lifted.

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PROCEDURE - Lead Lifting, Fine Pitch Gull Wing Components

1. Figure 11: Gently place a pick behind the component lead to be lifted. Apply a soldering iron tip to the foot of the component lead. Apply slight force with the pick to lift the lead as the soldering iron reflows the joint.

   Select the component lead that needs to be lifted. Apply a soldering iron and solder braid to remove the excess solder from the joint.
   
   
2. Gently place a pick behind the component lead to be lifted. Apply a soldering iron tip to the foot of the component lead. Apply slight force with the pick to lift the lead as the soldering iron reflows the joint. (See Figure 11).
   
   
3. Visually inspect, or electrically test, to ensure that the lead has been lifted. See (Figure 12).
   
   
4. If the lead needs to be reconnected, gently push the lead down until it touches the pad and solder.
   
   
5. If required, clean the flux residue and inspect.

Figure 12: Visually inspect, or electrically test, to ensure that the lead has been lifted.