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PCB Pad Repair

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Lifted pad on a circuit board (Adafruit)
A through-hole pad that has come away from the board and ridden up the component lead, still carrying its solder (photo: Bill Earl, Adafruit, CC BY-SA).[1]

PCB pad repair deals with a solder pad (a land) that has lifted, torn or corroded away from the board, on either a through-hole or a surface-mount footprint. A lifted pad that is still whole can be glued back down; a missing one is replaced with a new copper pad bonded to the board, or the component lead is joined directly to the track that served the pad, or to the next point on the same net.[1][2][3]

Pads lift most often during desoldering, and also when a joint is reworked so many times that the adhesive bond between the copper and the board fails. Adafruit notes that they lift most easily on boards with thin copper or holes without through-plating.[1] Ray Carlsen warns that too much heat lifts pads and tracks, and so does pressing the iron into the joint.[4] On old machines, electrolyte from leaking capacitors and batteries also attacks pads, and twisting a leaking part off can lift pads and tracks it has weakened.[5]

When to use it

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Logic board desoldering faults (Macintosh Repair and Upgrade Secrets Fig 10-6)
Faults to look for after desoldering: 1, a pad lifted from the board; 2, a break between a pad and its track; 3, a track cut near a pad; 4, a solder bridge between a pad and a track (Larry Pina, Macintosh Repair & Upgrade Secrets, Figure 10-6).

Inspect every hole and pad under a magnifier after removing a part, on both sides of the board.[4][6] Larry Pina lists the faults to look for as a lifted pad, a break between a pad and its track, a cut track near a pad, and a solder bridge between a pad and a track.[6]

  • A pad that has lifted but is still in one piece and still joined to its track can be re-bonded with epoxy.[2]
  • A pad that is torn, missing or eaten away is replaced, or bypassed by joining the lead to its track.[3][1]
  • A pad whose plated hole has torn out with it on a double-sided board has also lost the connection to the other side; repair the hole as in Via and Through-Hole Repair.[4]
  • On a multilayer board, a pad may connect through its plated hole to inner layers. Pina warns that a lifted pad on the Macintosh 128K's multilayer board is hard to repair for this reason.[6]
  • Where the track that served the pad is also damaged, see PCB Trace Repair or Jumper Wire Repair.

Safety

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  • Unplug the machine and remove any batteries before working on the board.[7]
  • Rosin (colophony) flux fume can cause occupational asthma. Use fume extraction while soldering.[8]
  • Scraping solder mask and board material can generate static charge; take anti-static precautions.[3]
  • Do not heat-cure epoxy at a temperature the parts on the board cannot tolerate.[9]

Tools and materials

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  • A temperature-controlled iron, flux, leaded solder and desoldering braid; see Recommended Tools and Through-Hole Desoldering.
  • A knife or scraper for removing the damaged pad and the solder mask from the track that served it.[3][1]
  • Clear two-part epoxy, with a colour agent if wanted.[9]
  • Replacement pads. Commercial pads are made from copper foil, are generally supplied solder-plated, and come in many sizes and shapes; a pad can also be cut from copper sheet.[3][10] Pads with a dry-film adhesive backing are bonded with a heated bonding tip or press.[11]
  • Polyimide (Kapton) tape for holding a new pad in place.[3]
  • Fine insulated wire, such as 30 AWG Kynar wire-wrap wire, for joining a lead or terminal to its track.[12][13]
  • A drill bit or ball mill turned by hand, to clear epoxy out of a plated hole.[3]
  • A magnifier and a multimeter.[6]

Procedure

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Identify the connection

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  1. Find what the pad connected to: follow its track on the board and check it against the schematic or the part's pin table.[12]
  2. Check whether the track that served the pad is still sound, and whether the pad has a track on the other side of the board or an inner-layer connection.[6][4]
  3. Clean the area with flux and braid, then alcohol, and inspect it under magnification.[12][3]

Re-bond a lifted pad that is still whole

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This is Circuit Technology Center's epoxy seal method, procedure 4.4.1, rated Medium conformance.[2]

  1. Clear anything that stops the pad lying flat, without stretching or tearing it.[2]
  2. Mix the epoxy.[2]
  3. Work a little epoxy under the whole pad with the tip of a knife or scraper.[2]
  4. Lay a piece of polyimide tape over the pad and press it down into the epoxy onto the board.[2]
  5. Add epoxy round the sides of the pad as needed, and cure it.[2][9]
  6. Clear any epoxy from the plated hole with a ball mill or drill turned by hand, so that the hole wall is not damaged.[2]
  7. Fit the component and solder it.[2]

A re-bonded pad has no metallic connection to the plated hole behind it; the component's solder joint restores the circuit, or an eyelet or wire can be added as in Via and Through-Hole Repair.[2]

Join the lead to the track (through-hole)

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Lifted pad repaired by folding the lead onto the trace (Adafruit)
The same pad repaired: the lead bent flat along the track that served the pad and soldered to it (photo: Bill Earl, Adafruit, CC BY-SA).[1]

This is the simplest repair for a through-hole part.[1]

  1. Remove the lifted pad if it is loose, cutting it free from its track.[3]
  2. Scrape the solder mask off a short length of the track that served the pad, down to bare copper.[1]
  3. Flux and tin the exposed track.[3]
  4. Fit the component, and bend its lead over flat along the track.[1]
  5. Solder the lead to the track.[1]
  6. If the lead will not reach, follow the track to the next via and run a wire from the lead to it, or to the leg of the nearest component on the same track; see Jumper Wire Repair.[1]

Fit a replacement pad

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This follows Circuit Technology Center's land repair, epoxy method (procedure 4.5.1) and its surface-mount pad repair (procedure 4.7.1); both are rated Medium conformance.[3][10]

  1. Remove the damaged pad and a short length of its track.[3]
  2. Scrape off any epoxy residue, contamination or burnt material from the board, and the solder mask from the track.[3]
  3. Make sure the area is smooth and flat; repair exposed fibres or deep scratches in the board first (see Burnt PCB Repair).[3]
  4. Flux and tin the end of the track, and clean the area.[3]
  5. Choose a replacement pad that matches the original, and trim it so that its tail overlaps the track by at least twice the track width.[3]
  6. Spread a little epoxy where the pad will sit.[3]
  7. Put polyimide tape over the new pad and use it to place the pad exactly on its position.[3]
  8. Cure the epoxy, then remove the tape and check the alignment.[3][9]
  9. Lap-solder the pad's tail to the track with as little flux and solder as will make the joint, at least 3 mm from the pad where the layout allows.[3]
  10. Coat the lap joint with epoxy, and run more epoxy round the pad's edge for extra strength; cure it.[3]
  11. For a through-hole pad, clear any epoxy from the hole with a ball mill or drill turned by hand.[3]
  12. Fit the component and solder it.[3]

Pads with a film adhesive backing are fitted the same way, except that the adhesive is scraped off the joint area of the tail before trimming, and the pad is bonded with a heated tip for about 5 seconds through tape and then 30 seconds directly. Circuit Technology Center warns that too much bonding pressure can cause measling in the board or slide the pad out of place.[11]

Surface-mount pads

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Atari Jaguar U38 replaced, with the pad repair (retrostuff)
An Atari Jaguar regulator, U38, refitted after three pads lifted with the old chip; the pads and the track to R169 were rebuilt with Kynar wire (photo: rosewood, retrostuff.org).[12]

A surface-mount pad can be replaced as above, or the component terminal can be joined to its track with a wire. Circuit Technology Center accepts a wire soldered to a component end that sits off its pad, and a wire soldered parallel to a track or pad.[14]

  1. Find where the missing pad's track goes: to a via, a resistor or another pin.[12]
  2. Fit the part on its remaining pads.[12]
  3. Solder a short fine wire from the terminal or pin over the missing pad to the nearest sound point on its track, such as a via. On the Atari Jaguar, Retrostuff rebuilt three pads at U38 this way.[12]
  4. Secure the wire with epoxy if it is not held by the part.[15]

Checking the repair

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  • Measure continuity from the component lead or terminal to the next point on its net, and on a double-sided board through to the other side.[4][16]
  • Check for shorts between the repaired pad and its neighbours, especially between pins on different nets.[12]
  • Check the width and spacing of a replacement pad against its neighbours.[3]
  • Circuit Technology Center checks a re-bonded pad with the tape test of IPC-TM-650 method 2.4.1.[2]
  • Power the machine and test the circuit that uses the part.[7]

Common mistakes

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  • Too much heat, or pressing the iron into the joint, lifts the pad that is being worked on and those beside it.[4]
  • Pulling a part before every pin is free tears pads away with it. Retrostuff lifted three pads with the Jaguar's U38, and a reader lifted one pad and then its neighbour.[4][12]
  • Twisting off a leaking capacitor lifts the pads and tracks that the electrolyte has weakened. Heat both pads together with hot air or two irons instead.[5]
  • Reheating pads that sit on large copper areas. Minuszerodegrees avoids it on the IBM PC AT supply by cutting the old capacitor's legs a few millimetres above the board and soldering the new part to the stubs.[17]
  • Leaving epoxy in a plated hole, so that the lead will not go in.[3]
  • Too much pressure on a film-adhesive pad, which can cause measling or move the pad.[11]
  • Re-bonding a pad on a multilayer board and assuming the inner-layer connection survived; check it with a meter.[6][2]

Worked examples on this wiki

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References

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  1. ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 Adafruit Learning System, Adafruit Guide To Excellent Soldering, "Common Soldering Problems", sections "Lifted Pad" and "Repairing a Lifted Pad" (Bill Earl): pads lift most often when desoldering, or when a joint is overworked until the adhesive bond fails; especially common on boards with thin copper or no through-plating; fold the lead over to a still-attached trace, scraping off solder mask; or run a jumper to the next via, or to the leg of the nearest component. Retrieved 2026-10-25.
  2. ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 Circuit Technology Center, "4.4.1 Lifted Land Repair, Epoxy Seal Method", IPC-7721 numbering: advanced skill, Medium conformance; remove obstructions without stretching the land; epoxy under the land, pressed down through high-temperature tape; double-sided and multilayer boards may need an eyelet; remove epoxy from the hole with a hand-turned ball mill or drill; no intermetallic connection to the plated hole, the solder joint restores it; tape test per IPC-TM-650 2.4.1. Retrieved 2026-10-25.
  3. ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 3.20 3.21 3.22 3.23 3.24 Circuit Technology Center, "4.5.1 Land Repair, Epoxy Method": advanced skill, Medium conformance; replacement lands of solder-plated copper foil in many sizes, or cut from copper sheet; remove the defective land and a short length of its circuit; scrape off residue and burnt material (abrasion can generate electrostatic charges); surface smooth and flat; overlap at least 2 times the circuit width; epoxy under the land, placed with high-temperature tape; lap solder at least 3.00 mm from the termination where possible; epoxy over the joint and round the perimeter; clear the hole by hand; evaluate by visual examination, measurement of width and spacing, and continuity. Retrieved 2026-10-25.
  4. ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Ray Carlsen, "Replacing IC chips in Commodore equipment": Commodore boards are double-sided with plated-through holes; every hole must be cleared and every pin free before the chip is lifted, or pins break off and the board is damaged; examine both sides of the board with a strong light and a magnifier after removal; torn plating breaks the circuit from top to bottom; too much heat, or pressing the iron into the solder, lifts pads and traces. Repair notes. Retrieved 2026-10-25.
  5. ↑ 5.0 5.1 Acorn A5000 Capacitor Guide, on this wiki: remove surface-mount electrolytics by heating both pads together with hot air or two irons; twisting a leaking part off can lift pads and tracks weakened by electrolyte.
  6. ↑ 6.0 6.1 6.2 6.3 6.4 6.5 Macintosh 128K RAM Chip Replacement, on this wiki, citing Larry Pina, Macintosh Repair & Upgrade Secrets (1990), Figure 10-6 and p. 177: examine every hole for lifted pads, breaks between pad and trace, cut traces and solder bridges; a lifted pad on the multilayer board is hard to repair because the pads are joined to plated holes connected to inner layers.
  7. ↑ 7.0 7.1 Battery Explosion, Capacitor or Corrosion Damage, on this wiki: take loose cells out before cleaning; after repair, test every function that passes through the repaired area.
  8. ↑ Health and Safety Executive, Controlling health risks from rosin (colophony) based solder fluxes, INDG249.
  9. ↑ 9.0 9.1 9.2 9.3 Circuit Technology Center, "2.7 Epoxy Mixing and Handling": cure 24 hours at room temperature or 4 hours at 150 °F (65 °C); some components are sensitive to high temperatures. Retrieved 2026-10-25.
  10. ↑ 10.0 10.1 Circuit Technology Center, "4.7.1 Surface Mount Pad Repair, Epoxy Method": Medium conformance; commercially available solder-plated copper-foil replacement pads bonded with liquid epoxy, with the same steps as the land repair. Retrieved 2026-10-25.
  11. ↑ 11.0 11.1 11.2 Circuit Technology Center, "4.5.2 Land Repair, Film Adhesive Method": High conformance; dry-film adhesive-backed lands bonded with a bonding press or iron; scrape adhesive from the joint area only; 5 seconds through tape to tack, then 30 seconds; excessive bonding pressure may cause measling or move the new circuit. Retrieved 2026-10-25.
  12. ↑ 12.0 12.1 12.2 12.3 12.4 12.5 12.6 12.7 12.8 Atari Jaguar Power Regulator Replacement, on this wiki, citing rosewood, "Atari Jaguar Power/Sound Fix and Rotary Controller", retrostuff.org, 21 August 2016: three pads lifted with U38 and rebuilt with Kynar wire to where their traces went (pad 7 to R169 and its via, pad 3 to the via on its right); a reader lifted one pad and then the next; clean with flux and braid; check new joints for bridges between pins on different nets.
  13. ↑ EEVblog Electronics Community Forum, "Wire for trace repair?", July 2022: #30 AWG Kynar wire-wrap wire is the traditional choice for patching logic-level signals. Community source. Retrieved 2026-10-25.
  14. ↑ Circuit Technology Center, "6.1 Jumper Wires", termination figures for chip components, pads and conductors: acceptable, wire soldered to a component end lifted off its pad; acceptable, wire soldered parallel to a conductor or pad. Retrieved 2026-10-25.
  15. ↑ Circuit Technology Center, "4.2.4 Conductor Repair, Surface Wire Method": bond the wire to the board with adhesive, epoxy or Wire Dots. Retrieved 2026-10-25.
  16. ↑ SparkFun Electronics (contributor bboyho), "How to Work with Jumper Pads and PCB Traces": test connections with a multimeter's continuity setting. CC BY-SA 4.0. Retrieved 2026-10-25.
  17. ↑ IBM PC AT Capacitor Replacement Guide, on this wiki, citing minuszerodegrees.net's "Solder new capacitor to old legs" diagrams: the pads sit on copper pours and lift easily.
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