Wire-wrap tutorial

Sooner or later you'll be in need of removing (easy) or adding (more difficult) a wire-wrap connection ...

You need:

• A good wire stripper,
• a decent wire-wrap tool (a hand-driven one is all you need),
• a wire cutter,
• isolated 30 AWG / 0,25mm wire,
• a post strip as exercise material,
• good lighting,
• a magnifying glass or an illuminated magnifying glass, and
• some practice.

Depending on the quality of your eyesight, you may need to use a magnifying glass or an illuminated magnifying glass for some or all of the following steps.

You need a good wire stripper, otherwise you may:

• not be able to remove the insulation properly or at all,
• tear the wire instead of removing the insulation, or
• damage the wire so that it breaks at some point in the future.

Removing a wire-wrap connection

1. Place the wire wrap tool with the center hole on the post.
2. Apply little pressure and turn the tool about 8 to 10 turns counterclockwise until the wire is unwound. If in doubt, use some more turns as this is better than too few.
3. Remove the tool from the post.
4. Make sure to remove all wire parts.

Adding a wire-wrap connection

1. Cut a piece of wire, calculate 2 cm for each wrap, add the distance between the posts and about 5 to 10 mm for some play.
2. 2 cm is enough for 6 wraps, adjust the length depending on the number of wraps you require; calculate with 0,34 cm per wrap. Don't use fewer than 4 wraps, as this might weaken the connection. As far as I know DEC used 6 wraps for data connections normally.
3. If the wire is longer than about 6 cm, strip 2 cm insulation off each end.
4. If the wire is shorter, strip 2 cm of insulation from one end only; you'll remove the insulation from the other end after the wire has been wrapped on the end that was stripped first. It can be difficult to strip the second end on short wires because you can't get a good grip on the wire.
5. Thread the stripped wire end into the wire wrap tool, making sure to use the correct (outer) hole.
6. Bend the rest of the wire rectangular to the tools axis.
7. Place the wire wrap tool with the center hole on the post.
8. Fix the wire's free end with your fingers or tweezers.
9. Apply little pressure and turn the tool about 8 turns clockwise until the wire is completely wrapped around the post.
10. If in doubt, use some more turns as this is better than too few.
11. Remove the tool from the post.
12. Inspect the wire-wrap with your magnifying glass or illuminated magnifying glass.
13. Strip the other end of the wire if not already done.
14. Bend the stripped end upwards (towards the posts).
15. Thread this end into the wire wrap tool, making sure to use the correct (outer) hole.
16. Place the wire tool with the center hole on the post without losing the wire end from the tool.
17. You may have to thread the wire as well as the post into the tool at the same time (finicky) when the wire is short.
18. Fix the wire's middle part end with your fingers or tweezers.
19. Proceed as with the first end of the wire, turning the tool about 8 turns clockwise until the wire is completely wrapped around the post.
20. Finally use a multimeter to check the proper contact.

Don't be frustrated if you need more than a dozen attempts to get satisfactory results, with a little practice it will get better. Connecting two posts next to or near each other is difficult, so start with more distant ones.