A method of creating
prototype electronics boards that is more
specific, more
permanent, and less elecronically
noisy than using a
protoboard, and less
messy,
dangerous, and
carcinogenic than
soldering. All electronic components that are to be used in the board are mounted in special
mounts that have long, stiff wire prongs beneath. These mounts are inserted into a generic
breadboard, and prongs are connected to each other by wrapping thin
wires around the legs.
To wrap one end of a wire:
- Strip off about .75 cm from the end of the wire.
- Take out your overpriced (because the patent on the design is aggressively enforced) wire wrap tool.
- Insert the bare wire into the guide on one side of the tool's shaft.
- Guide the tool's shaft over the prong you wish to wrap.
- Spin the tool gently, keeping a gentle downward pressure on the prong. If you do it right, wire should play out from the guide, and form a nice, tight coil around the prong.
- If you are too gentle in your twisting, your wire won't be tight enough.
- If you are too forceful in your twisting, your wire will break.
- If you keep too much downward pressure on the prong, your wire will wrap over itself, then break.
- If you don't keep enough downward pressure on the prong, your wire coil won't be tight, and may come off easily.
- Now wrap the other end of the wire around wherever you want it to be. Make sure when you cut the wire, you leave enough play to get the wire onto the end of your tool!
Wire wrapping is a tricky craft to learn, but after you've made your third board or so, it should come naturally.
There are a number of drawbacks to wire-wrapping. Among them:
- You need very thin, very fragile wire to do it. If you want to create a proto-board that controls, say, an electric motor, you may want to consider solder instead.
- The more connections you have, the more spaghetti-like the underside of your board will be. Using black wire for your ground lines and red wire for your power lines is a must. Consider using other colors as warranted.
- The fact that you are wrapping on the opposite sides of your chips means that you have to mentally 'flip' everything on the board when you make connections. The potential for error is great, and unless you verify every connection immediately after it is made, you may spend unnecessary amounts of time hunting down that bad connection.
I find that the best way to to a wire-wrap board is to draw out the physical chip diagram and connections in
ink on thin paper, then flip the paper over and trace in the same connections through the paper with
pencil. Then, as I wrap the board, every time I complete a connection, I trace over it with
pen. Also, I wrap all the ground connections and power connections first, since it gives a
hint as to the layout of the chips (a forest of
prongs without any reference is kind of
intimidating).