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PCB Trace Repair

From RetroTechCollection
SparkFun green wire repair of a cut trace to a via
A trace cut by accident on a SparkFun shield, repaired with a short green wire from the TX jumper pad to a via on the same net. The via's solder mask was scraped off to take the solder.[1]

PCB trace repair restores a printed copper track that has cracked, corroded through, been cut or torn, or burnt open. The damaged copper is cut back to where it is still firmly bonded to the board, and the gap is bridged with a wire, a strip of copper foil or, for a short gap in a signal track, conductive ink. The joints are made on the surviving copper beside the break, and the repair is then sealed with epoxy or solder mask.[2][3][4]

The methods here come from the rework and repair procedures that IPC publishes as IPC-7711/7721. IPC sells the standard itself. Circuit Technology Center publishes a repair guide under the same procedure numbers, and Chemtronics publishes step-by-step guides based on it.[5][4] Circuit Technology Center places consumer products and some computer products in Class 1, general electronic products, and says that Class 1 and 2 products may use its Medium and Low conformance repairs where they suit the product's function.[5] A wire across a break is a Medium conformance repair; a copper foil replacement coated in epoxy is High.[3][2]

A trace that runs into a pad, a via or a burnt area needs the sibling repair as well: see PCB Pad Repair, Via and Through-Hole Repair and Burnt PCB Repair. When the most practical route is a wire from one component leg to another, use Jumper Wire Repair.

When to use it

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SGI Origin 2000 power supply Q113 trace damage (Pentium)
The trace at the centre pad of Q113 on an SGI Origin 2000 power supply board, eaten through by leaked capacitor electrolyte (photo: Pentium, IRIX Network forum).

Use a trace repair when a single track is open between two points that should be joined, and the copper on each side of the break is still bonded to the board. Typical causes on old machines:

  • Electrolyte from leaking batteries and capacitors, which eats tracks and vias. Clean and neutralise the board first, as described in Battery Explosion, Capacitor or Corrosion Damage.[6]
  • Cracks where a track meets a via, found on corroded Acorn A7000 boards far from the battery.[7]
  • A slipped knife or a careless cut. SparkFun's example is a TX track cut by mistake while an adjacent trace was being cut.[1]
  • Copper torn away with a part during desoldering. Ray Carlsen warns that too much heat lifts pads and copper tracks, and that a broken track hidden under a new chip or socket is very hard to find later.[8]

Recognise the break with a meter: measure continuity from one end of the net to the other, using the component pins at each end, then move one probe along the points in between until the reading stops; the break lies between the last good point and the first bad one.[9] Look at both sides of the board under magnification, because a track can be broken out of sight under a chip or a socket.[8] Continuity Testing and Signal Tracing covers the measurement.

Choosing a method
Damage Repair Notes
Short break in a signal track Wire lapped onto the track on each side Circuit Technology Center procedure 4.2.4, Medium conformance, intermediate skill[3]
Missing section of a track, wide or power track Copper foil (replacement conductor) soldered and coated with epoxy Procedure 4.2.1, High conformance, advanced skill[2]
Track lifted from the board but not broken or stretched Re-bond it with epoxy Procedure 4.1.1; not for a track that has been stretched or damaged[10]
No room on the surface for a bridge Wire through two drilled holes, run on the other side Procedure 4.2.5; check the drawings first so that the drill hits no other circuit[11]
Short gap in a signal track, no soldering nearby Silver conductive ink Many times the resistance of copper; see the limits below[12]
Long run, or the track is unreachable A point-to-point wire between component legs Jumper Wire Repair

Safety

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  • Unplug the machine and take out any batteries before working on the board.[6] On equipment with a picture tube, follow the CRT Discharge Procedure first.
  • Rosin (colophony) flux fume can cause occupational asthma. Use fume extraction while soldering.[13]
  • Scraping and grinding solder mask can generate static charge. Handle the board with the usual anti-static precautions.[14]
  • Epoxy and conductive ink are applied by hand; mix and cure them as their makers direct. Do not heat-cure at a temperature the parts on the board cannot tolerate.[15][4]

Tools and materials

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  • A craft knife or scalpel and a hardened scraper for cutting copper and removing solder mask. Chemtronics also suggests a rotary-tool grinding bit held in the hand.[2][4]
  • A magnifier or microscope, and a multimeter with a continuity range.[2]
  • A temperature-controlled soldering iron with a fine tip, liquid or paste flux, leaded solder and desoldering braid; see Recommended Tools and Through-Hole Soldering.
  • Polyimide (Kapton) tape to hold the new conductor while it is soldered.[2]
  • Isopropyl alcohol and lint-free wipes for cleaning.[2][4]
  • A replacement conductor, chosen from the table below.
  • A sealing coat: clear two-part epoxy (a colour agent can be stirred in to match the board), an acrylic overcoat pen, or UV-cure solder mask.[15][16][17]
Replacement conductors
Conductor Properties that matter Source
30 AWG wire-wrap wire 0.255 mm silver-plated soft copper with Kynar (PVDF) insulation; the traditional wire for patching logic-level signals. PVDF melts at about 177 °C, below the 183 °C melting point of 63/37 tin-lead solder, so the insulation shrinks back from a joint held hot for long. [18][19][20][21][22]
PTFE-insulated wire PTFE melts at 327 °C. One Atari XEGS memory-upgrade builder changed to Teflon-insulated wire after the kit wire's insulation melted back. [23][24]
Solderable enamelled (magnet) wire Polyurethane enamel that burns off in the solder: SynFlex quotes solderability from a 390 °C solder bath without stripping, under IEC 60317-20. Repairers burn the enamel off with the iron. [25][20]
Solid tin-lead plated copper, 22 to 32 AWG Circuit Technology Center's recommended jumper wire, insulated with Kynar, Milene, Kapton or Teflon. It says silver-plated wire must not be used, because it can corrode under some conditions. [26]
One strand of stranded hook-up wire Uninsulated, flexible, and thin enough that heat from soldering one end does not travel to the other. [20]
Copper foil or a ready-made replacement conductor Match the width and thickness of the track; most tracks are 1 oz/ft² copper, 1.37 mil thick. Commercial replacement conductors carry a thin anti-oxidation coat that must be abraded off before soldering. [4][2]
Silver conductive ink (CircuitWorks CW2200) 0.02 to 0.05 Ω/sq/mil, 0.00005 to 0.000125 Ω·cm, maximum 205 °C. Copper is 1.68 µΩ·cm, so the ink has about 30 to 75 times its resistivity. [12][27]

The two sources disagree on wire plating: wire-wrap wire is silver-plated, and the EEVblog forum names it as the traditional choice, while Circuit Technology Center rules silver-plated wire out.[18][20][26]

Match the cross-section of the replacement to the track it replaces. Circuit Technology Center warns that the circuit's width, spacing and current-carrying capacity must not be reduced, and gives these solid-wire equivalents for tracks of 2 oz copper:[3][2]

Solid wire equivalent to a 2 oz copper track (Circuit Technology Center, procedure 4.2.4, Table 1)
Track width Equivalent solid wire
0.25 mm (0.010 in) #34, 0.15 mm (0.006 in)
0.38 mm (0.015 in) #32, 0.20 mm (0.008 in)
0.50 mm (0.020 in) #31, 0.23 mm (0.009 in)
0.78 mm (0.031 in) #29, 0.28 mm (0.011 in)
2.08 mm (0.082 in) #26, 0.46 mm (0.018 in)
3.18 mm (0.125 in) #23, 0.58 mm (0.023 in)

Procedure

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Prepare the break

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  1. Switch off, unplug the machine and remove the board if it has to come out to reach both sides.
  2. Clean the area with isopropyl alcohol.[2]
  3. Find both ends of the break with the meter, and mark the sound copper on each side. On a complex board, the next exposed copper on the same net may only be found from the board's layout or schematic.[1]
  4. Cut out the damaged section with a knife, back to where the track is still well bonded to the board. Heat from the iron helps loose copper come away.[2]
  5. Check that each cut goes right through before pulling a damaged piece away, or the rest of the track or a pad will lift with it.[4]
  6. Scrape the solder mask off at least 3 mm of each track end, holding the blade upright and scraping from side to side. Scrape lightly so that the copper underneath is not thinned.[4][14]
  7. Clean off the scraped particles with alcohol.[4]
  8. Apply a little flux to each exposed end, tin it, and remove any excess with braid. Clean the area again.[2][4]

Bridge a short break with wire

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PCB trace repair lap joint (diagram)
A wire or foil bridge in plan and section: damaged copper cut out, mask scraped back, the new conductor overlapping each end by at least twice the trace width, joints at least 3 mm from the pad, and an epoxy coat over the top.[2][3][4]

This is Circuit Technology Center's surface wire method.[3]

  1. Choose a wire with at least the cross-section of the track; 30 AWG is the usual size for logic signals (see the tables above).[3][20]
  2. Cut it to length, strip it if insulated, and tin the ends. Bare wire is acceptable for a short repair that crosses no other conductor.[3]
  3. Lay the wire along the track so that it overlaps each end by at least twice the track width. Hold it with polyimide tape placed away from the joints.[3][4]
  4. Keep each joint at least 3 mm from the nearest pad where the layout allows, so that it does not reflow when that pad is next soldered.[3][4]
  5. Flux the overlap and lap-solder one end, checking that the wire lies along the track.[3]
  6. Form the wire to follow the path of the missing copper, then solder the other end.[3]
  7. Remove the tape and clean the area.[3]
  8. Bond the wire to the board with epoxy, adhesive or adhesive dots. Encapsulate a joint that sits closer to a neighbouring conductor than the original spacing, or that lies under a component.[3]

Replace a missing section with copper foil

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This is Circuit Technology Center's foil jumper method, procedure 4.2.1, which Chemtronics also describes.[2][4]

  1. Choose a replacement conductor of the same width and thickness as the track, and cut it to length with enough to overlap each end by at least twice the track width.[2]
  2. Abrade both faces lightly to remove the protective coating, clean it, and tin the ends.[2]
  3. Tape it in place with polyimide tape. On a straight run, align both ends at once; on a bent run, align one end only.[4]
  4. Flux and lap-solder the first end, at least 3 mm from the nearest termination where possible.[2]
  5. Bend the foil to the shape of the missing track, holding it at the bend with one wooden stick and forming it with another. Fold a wide foil over on itself to make a sharp corner.[2]
  6. Tape the formed foil in place, flux and lap-solder the second end, then remove the tape and clean the area.[2]
  7. Coat the top and sides of the foil with mixed epoxy, which both insulates it and bonds it to the board.[2]

Replacement conductors are also made with a dry epoxy film on the back, which is bonded with a heated bonding tip: about 5 seconds through tape to tack it, then 30 seconds directly on the conductor. The board surface must be smooth and flat for this method.[28]

Route the bridge through the board

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Where there is no room for a bridge on the damaged side, Circuit Technology Center drills a hole slightly larger than the wire beside each end of the track, passes the wire through from the other side, bends the stripped ends over the prepared track ends and lap-solders them. Check the board's drawings before drilling so that no surface or inner track is hit.[11]

Conductive ink

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Ink has many times the resistance of copper and takes solder only after a heat cure, so it suits a short gap in a signal line away from joints that will be soldered again.[12]

  1. Scrape and clean the track ends as above.[29]
  2. Shake the pen for 30 seconds so that the silver is dispersed.[12]
  3. Draw the new track across the gap, from one exposed end of the track to the other.[29]
  4. Let it cure. Chemtronics' data sheet gives tack-free in 3 to 5 minutes, conductivity within 30 minutes, and a 5-minute cure at 120 to 150 °C for the best conductivity; its how-to guide allows at least one hour before overcoating.[12][29]
  5. Overcoat the ink with an overcoat pen or epoxy.[29]

The cured ink can be soldered only after a heat cure, at 177 °C for less than 5 seconds, and its rated maximum temperature is 205 °C.[12]

Re-bond a lifted track

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If the track has lifted but is not broken or stretched, clear anything under it, work a little mixed epoxy under its whole length with a knife tip, press it down into the epoxy, and coat its top and sides. Circuit Technology Center does not use this method on a track that has been stretched or damaged.[10]

Seal the repair

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  1. Mix the epoxy as its maker directs; Circuit Technology Center mixes its packaged epoxy for at least a minute and stirs it for at least two minutes.[15]
  2. Spread it over the repair with a sharpened wooden stick or a foam swab, masking nearby parts with polyimide tape.[2][4]
  3. Cure it. Circuit Technology Center cures its epoxy for 24 hours at room temperature or 4 hours at 65 °C (150 °F), warning that some components are sensitive to high temperature.[15]

An acrylic overcoat pen is quicker: Chemtronics' CW3300 dries in 5 to 10 minutes, is rated from −55 to 125 °C and comes off with acetone, and Chemtronics advises using an overcoat pen only where the coating will not meet soldering temperatures.[16][4] UV-cure solder mask is a third option. The data sheet for UR-3100, a one-part UV-cure mask sold by Florida CirTech, gives a cure energy of 700 to 1000 mJ/cm² and reports that the cured mask passed three 10-second floats on a 260 °C solder bath. Cure a syringe-applied UV mask as its maker directs.[17]

Checking the repair

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  • Measure continuity from the component pin at one end of the net to the component pin at the other, as well as across the new joints. A wire or foil bridge should read as a direct connection.[1][9]
  • Check for shorts between the repaired track and each neighbouring track.[30]
  • Expect more resistance from ink. At 0.02 to 0.05 Ω/sq/mil, a 1 mil thick ink line has a resistance of 0.02 to 0.05 Ω for every square of its length.[12]
  • Inspect the repair under magnification: the conductor aligned with the track and overlapping each end by at least twice the track width, and the epoxy coat even in texture.[2][3]
  • Look for solder splashes between the repair and nearby pads. A Psion Series 5mx flex repair failed twice because tiny solder splashes shorted adjacent pads.[31] Sinclair's service manual warns that a hairline of solder splatter can measure several ohms and cause very misleading symptoms.[32]
  • Circuit Technology Center checks a re-bonded track with the tape test of IPC-TM-650 method 2.4.1.[10]
  • Power the machine and test every function that passes through the repaired area.[6]

Common mistakes

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  • Holding the iron on old copper for too long lifts the pads and tracks next to the repair.[8]
  • Tearing out a damaged section before the cut is complete lifts the good track or its pad with it.[4]
  • A lap joint right next to a pad reflows and moves when that pad is soldered. Keep joints 3 mm away where the layout allows.[3][4]
  • A thin wire on a power or ground track reduces the current the track can carry. Atari's own Tech Tip 14 for the 5200 adds a 16-gauge bus wire in plastic sleeving at the POKEY because the ground track there was inadequate.[3][33]
  • An unbonded wire is free to move at its joints. Anchor it beside each joint and along its length.[20][3]
  • Kynar insulation melts below the melting point of tin-lead solder and shrinks back from a joint held hot for long, leaving bare wire. Use less heat, or PTFE-insulated wire.[21][22][24]
  • Electrolyte left under a repair keeps attacking the copper round it. Clean and neutralise the board first, and clean again if deposits come back.[6]
  • Conductive ink takes solder only after a heat cure, and then only briefly at 177 °C, and it has many times the resistance of copper, so it fails where a track carries current or a part beside it is later soldered.[12]

Worked examples on this wiki

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References

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  1. ↑ 1.0 1.1 1.2 1.3 SparkFun Electronics (contributor bboyho), "How to Work with Jumper Pads and PCB Traces", section "Rerouting and Green Wire Repair": the TX trace cut by accident, found with a multimeter, and repaired with wire to a tented via; on complex boards the board's layout may be needed to find the next exposed copper. CC BY-SA 4.0. 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 2.13 2.14 2.15 2.16 2.17 2.18 2.19 2.20 2.21 Circuit Technology Center, "4.2.1 Conductor Repair, Foil Jumper, Epoxy Method": advanced skill, High conformance; circuit width, spacing and current capacity must not be reduced; trim the damaged circuit back to good bond (heat may be applied); scrape mask from the ends; tin; match width and thickness; overlap at least 2 times the circuit width; joint at least 3.00 mm from the termination where possible; abrade the protective coating; bend with two wood sticks, fold wide circuits; coat top and sides with epoxy; evaluate by visual examination and electrical test. 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 Circuit Technology Center, "4.2.4 Conductor Repair, Surface Wire Method": intermediate skill, Medium conformance; Table 1, solid wire equivalents for 2 oz copper conductors; no reduction in cross-sectional area; non-insulated wire for short repairs where conductors are not crossed; overlap at least 2 times the circuit width; joint at least 3.00 mm from the termination; bond with adhesive, epoxy or Wire Dots; encapsulate joints where spacing is reduced or beneath a component. Retrieved 2026-10-25.
  4. ↑ 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 4.11 4.12 4.13 4.14 4.15 4.16 4.17 4.18 Chemtronics, "HOW-TO: PCB Trace Repair Using Foil Jumper & Epoxy Overcoat", based on IPC-7721 4.2.1: repair at least 3 mm from contacts that will be soldered; check the cut is complete before pulling off the damaged trace; scrape at least 3 mm of overcoat, lightly; most traces are 1 oz/ft² (1.37 mil); overlap at least twice the trace width; align both ends of a straight run at once; an overcoat pen may be used where the coating will not meet soldering temperatures; do not cure at a heat the components cannot tolerate. Retrieved 2026-10-25.
  5. ↑ 5.0 5.1 Circuit Technology Center, "1.0 Foreword", circuit board repair guidebook: the guidebook follows IPC J-STD-001, IPC-A-600, IPC-A-610, IPC-7711 and IPC-7721; Class 1 general electronic products include consumer products and some computer products; conformance levels High, Medium and Low; Class 1 and 2 products may use Medium or Low procedures where suitable. Retrieved 2026-10-25.
  6. ↑ 6.0 6.1 6.2 6.3 Battery Explosion, Capacitor or Corrosion Damage, on this wiki: sections "Cleaning" (take loose cells out; deposits that come back mean electrolyte is still on the board, so clean again), "Assessing the damage" (eaten traces) and "Checking the repair" (test every function that passes through the repaired area); "Broken traces" (a via corroded through).
  7. ↑ Acorn A7000 Troubleshooting Guide, on this wiki, citing Ian Jeffray on the stardot forum: cracked tracks where a track meets a via, on data and address lines far from the battery.
  8. ↑ 8.0 8.1 8.2 Ray Carlsen, "Replacing IC chips in Commodore equipment": too much heat lifts pads and copper traces; a broken trace hidden under a new chip or socket is very hard to find. Repair notes. Retrieved 2026-10-25.
  9. ↑ 9.0 9.1 Sinclair QL RGB Port Repair, on this wiki, "Continuity checks, power off": measure from one end of the line to the other, then move the second probe to the points between until continuity stops; the break lies between the last good point and the first bad one.
  10. ↑ 10.0 10.1 10.2 Circuit Technology Center, "4.1.1 Lifted Conductor Repair, Epoxy Method": epoxy under and around a lifted circuit; not for a circuit that has been stretched or damaged; evaluation by tape test per IPC-TM-650 method 2.4.1. Retrieved 2026-10-25.
  11. ↑ 11.0 11.1 Circuit Technology Center, "4.2.5 Conductor Repair, Through Board Wire Method": drill through the board beside both ends, slightly larger than the wire; review circuit diagrams so no surface or internal circuit is damaged; wire on the opposite side, ends bent over and lap-soldered; not allowed where the wire will later go through mass soldering. Retrieved 2026-10-25.
  12. ↑ 12.0 12.1 12.2 12.3 12.4 12.5 12.6 12.7 Chemtronics, CircuitWorks Conductive Pens & Paint technical data sheet, CW2200STP, CW2200MTP, CW2205, rev. K (5/19): silver-filled polymer, 55 % silver; conductivity 0.02 to 0.05 Ω/sq/mil (0.00005 to 0.000125 Ω·cm); maximum temperature 205 °C; tack-free 3 to 5 minutes, conductive within 30 minutes; heat cure 5 minutes at 120 to 150 °C; low-temperature soldering to heat-cured traces at 177 °C for under 5 seconds; shake 30 seconds. PDF. Retrieved 2026-10-25.
  13. ↑ Health and Safety Executive, Controlling health risks from rosin (colophony) based solder fluxes, INDG249.
  14. ↑ 14.0 14.1 Circuit Technology Center, "2.3.5 Coating Removal, Grinding/Scraping Method": knife or scraper held perpendicular and moved side to side; abrasion can generate electrostatic charges. Retrieved 2026-10-25.
  15. ↑ 15.0 15.1 15.2 15.3 Circuit Technology Center, "2.7 Epoxy Mixing and Handling": mix the packaged epoxy for at least one minute and stir for at least two; colour agent optional; 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.
  16. ↑ 16.0 16.1 Chemtronics, CircuitWorks Overcoat Pen technical data sheet, CW3300, rev. L (7/18): acrylic conformal coating; −55 to 125 °C; dries in 5 to 10 minutes, heat cure 5 to 10 minutes at 93 °C; removable with acetone. PDF. Retrieved 2026-10-25.
  17. ↑ 17.0 17.1 Florida CirTech, UR-3100 Series UV Curable Solder Mask technical bulletin, revision 08-28-06: one-component, solvent-free UV-cure mask made by Sanwa Chemical; passed three 10-second floats at 260 °C; insulation resistance 1 × 1013 Ω; dielectric strength 1.7 kV/mil; cure energy 700 to 1000 mJ/cm² from high-pressure mercury lamps. PDF. Retrieved 2026-10-25.
  18. ↑ 18.0 18.1 Wikipedia, "Wire wrap": 30 gauge silver-plated soft copper wire insulated with a fluorocarbon, most commonly Kynar. Retrieved 2026-10-25.
  19. ↑ Wikipedia, "American wire gauge", table: 30 AWG is 0.0100 in (0.255 mm) in diameter. Retrieved 2026-10-25.
  20. ↑ 20.0 20.1 20.2 20.3 20.4 20.5 EEVblog Electronics Community Forum, "Wire for trace repair?", July and August 2022: jpanhalt (Kynar is thin and more heat-stable than PVC); rstofer (#30 AWG Kynar wire-wrap wire is the traditional choice for logic-level signals); David Hess (magnet wire whose insulation burns off with the iron; anchor the wire beside the joint and along its length, with thick cyanoacrylate for example); TC (a single strand of stranded wire is flexible and does not carry heat to the other joint). Community source. Retrieved 2026-10-25.
  21. ↑ 21.0 21.1 Wikipedia, "Polyvinylidene fluoride": sold as Kynar (Arkema); melting point around 177 °C. Retrieved 2026-10-25.
  22. ↑ 22.0 22.1 Wikipedia, "Solder": 63/37 tin-lead is eutectic and melts at 183 °C. Retrieved 2026-10-25.
  23. ↑ Wikipedia, "Polytetrafluoroethylene": melting point 327 °C. Retrieved 2026-10-25.
  24. ↑ 24.0 24.1 Atari XEGS Mods & Upgrades, on this wiki: a memory-upgrade builder found the kit wire's insulation melted back during soldering and changed to Teflon-insulated wire.
  25. ↑ SynFlex, SynWire V 155 data sheet: solderable polyurethane-enamelled round copper wire, class 155; solderable from a 390 °C solder bath without prior mechanical removal of the insulation; IEC/DIN EN 60317-20, NEMA MW 79-C. PDF. Retrieved 2026-10-25.
  26. ↑ 26.0 26.1 Circuit Technology Center, "6.1 Jumper Wires", Jumper Wire Selection: silver-plated wire must not be used because under some conditions it can corrode; recommended wire is solid insulated copper, tin-lead plated, 22 to 32 AWG with Kynar, Milene, Kapton, Teflon or equivalent insulation. Retrieved 2026-10-25.
  27. ↑ Wikipedia, "Electrical resistivity and conductivity", table of resistivities: copper 1.68 × 10−8 Ω·m at 20 °C. Retrieved 2026-10-25.
  28. ↑ Circuit Technology Center, "4.2.2 Conductor Repair, Foil Jumper, Film Adhesive Method": board surface must be extremely smooth and flat; replacement conductor with epoxy bonding film; hot bonding tip for 5 seconds through high-temperature tape to tack, then 30 seconds directly. Retrieved 2026-10-25.
  29. ↑ 29.0 29.1 29.2 29.3 Chemtronics, "HOW-TO: PCB Trace Repair With Conductive Ink": scrape and clean the break, draw the trace with a CircuitWorks conductive pen, allow at least one hour to cure, then overcoat with an overcoat pen or epoxy. Retrieved 2026-10-25.
  30. ↑ Battery Explosion, Capacitor or Corrosion Damage, on this wiki, section "Broken traces": after each repair, check continuity along the new path and check for shorts to neighbouring tracks.
  31. ↑ Psion Series 5 Hinge Cable Repair, on this wiki, citing David Savery: two attempts failed because tiny solder splashes shorted adjacent pads.
  32. ↑ Sinclair QL RGB Port Repair, on this wiki, citing Sinclair's QL service manual: hairline solder splatter can measure several ohms and give very misleading symptoms.
  33. ↑ Atari 5200 Joystick Pot Line Repair, on this wiki, citing Atari's Tech Tip 14 (3 July 1983): about 2 inches of 16 gauge bus wire in plastic sleeving from U7 pin 1 to the ground lead of C104, because of an inadequate ground trace.
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