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Replacing a single pin in a shrouded header

THT Published 22 October 2026 By The Solder Desk chisel 1.6 mm

Pulling one bent pin out of a 2.54 mm shrouded header without melting the housing is a containment problem: you have to deliver enough heat to the barrel while keeping the thermoplastic below 250 degrees C. The sequence matters more than the temperature.

Procedure

  1. 1

    Straighten the bent pin from the component side with flat pliers while the joint is still cold.

  2. 2

    Add a bead of fresh SAC305 and ROL0 flux to the solder-side joint to bring the alloy back to a known melting range.

  3. 3

    Tilt the board so the pin points down and away from the housing, then apply a 1.6 mm chisel at 350 degrees C for two seconds.

  4. 4

    Grip the pin with tweezers and pull gently as the alloy goes liquid; if it resists, add solder rather than force.

  5. 5

    Clear the barrel with 1.5 mm braid, straighten the replacement pin, and re-solder with a two-second dwell.

  6. 6

    Inspect the housing at 10x for whitening and check pin-to-pin alignment with a sacrificial mating connector.

Workshop notes

Work from the solder side, not the housing side

The housing is glass-filled nylon or LCP with a melting point between 260 and 290 degrees C; the barrel needs 240 degrees C to release. That 20 to 50 degree window is the entire job. Heat from the solder side with the board tilted so gravity pulls the pin out and away from the plastic, and never rest the iron on a pin next to the housing wall for more than two seconds.

One pin at a time with a heat shunt

On a 1.6 mm pad, a 1.6 mm chisel reaches reflow in about two seconds. Hold a pair of self-closing tweezers on the pin just above the board as a crude heat shunt if you are working on a dense row; it takes 30 to 40 degrees off the pin shank and keeps the housing from softening. Add fresh SAC305 to the joint first so the alloy goes liquid at 217 rather than fighting an already-oxidised joint.

Straightening before extraction

A bent pin cannot be pulled straight through the hole; it will drag on the barrel walls and tear the plating. Straighten the pin with flat pliers from the component side while the joint is cold, then reflow and pull. If the pin is kinked inside the housing, cut it flush with the housing face and push the remainder out from above with a 0.7 mm pin punch after reflow.

Practice drill

Take three scrap shrouded headers and replace the corner pin in each using this sequence, then inspect the housing for whitening or deformation under 10x. Whitened plastic around the pin means you were within 20 degrees of melting it, even if the joint looks fine.

Failure modes

Symptom Cause Treatment
Housing whitens or the pin shifts in the plastic Iron rested on the joint for more than two seconds, or heat applied from the housing side Work from the solder side with the board tilted, cap the dwell at two seconds, and use self-closing tweezers as a heat shunt
Barrel plating tears out with the pin Pin pulled before the alloy fully liquefied, or the pin was still bent on the way out Straighten cold, add fresh solder, wait for the fillet to drop flat, then pull with tweezers instead of pliers
New pin misaligned with the mating connector Pin soldered without the housing locating it, or the housing softened and moved Insert the pin through a sacrificial mating connector during soldering so the shell sets the position, then remove it after the joint cools

Supplies

  • 0.6 mm SAC305 solder wire
  • ROL0 no-clean flux pen
  • 1.5 mm desoldering braid
  • Replacement header pins

Tools

  • Station at 350 degrees C
  • 1.6 mm chisel tip
  • Self-closing tweezers
  • 0.7 mm pin punch and flat pliers

Safety

Heating a connector housing releases the same volatiles the moulding gave off when it was made; do this under extraction, not at a kitchen table. Pins under tension can eject when the solder releases - keep your face out of the line of fire.

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