How to Solder

How to Solder Enamel Wire

Enamel wire is copper wire covered with a thin insulating coating. Before solder will stick, the enamel coating must be removed or burned off.

Tools You Need

  • Enamel wire
  • Soldering iron (clean tip)
  • Solder
  • Flux
  • Exhaust fan to suck fumes
  • Tweezers
  • Sharp blade, sandpaper, or fiberglass pen
  • IPA
  • Multimeter

1. Remove the Enamel Coating

The copper must be exposed before solder will stick.

  • Scrape method: Gently scrape the end of the wire with a blade, sandpaper, or fiberglass pen until the copper looks shiny.
  • Burn and tin method: Add flux to the wire end, place solder on the iron tip, then hold the wire in the molten solder until the enamel burns away and the solder coats the copper.

For very fine enamel wire, the burn and tin method is often easier.

2. Tin the Wire

  1. Add flux to the exposed wire end.
  2. Touch the soldering iron to the wire.
  3. Add a tiny amount of solder.
  4. The wire end should become silver and shiny.

If the solder balls up or refuses to stick, there is still enamel on the wire.

3. Tin the Pad or Connection Point

Add flux to the solder pad, pin, or component leg. Then add a small amount of solder to it first. This makes the final join much easier.

4. Solder the Wire in Place

  1. Hold the tinned wire against the tinned pad.
  2. Touch the soldering iron to both parts.
  3. Wait just long enough for the solder to melt together.
  4. Remove the iron and keep the wire still while the solder cools.

5. Check the Joint

A good solder joint should be shiny, smooth, firmly attached, and not touching nearby pads or pins.

Use a multimeter in continuity mode to confirm the wire is connected properly.

6. Secure the Wire

Enamel wire is thin and can break easily. For repair work you may need to secure it so it cannot move.

  • UV mask
  • Kapton tape
  • Hot glue
  • Epoxy

Quick Tips

  • Use plenty of flux, not too much solder.
  • Tin both sides before joining them.
  • Do not pull on the wire after soldering.
  • If solder will not stick, clean more enamel off the wire.
  • For PCB jumper work, use the thinnest wire that is still strong enough for the job.