To build any electronics handicrafts, there are some wiring materials. I think most people are wiring circuit board with PTFE (Teflon) insurated wire. But the PTFE wire is not suitable for wiring material with solder due to following reasons.
- Wires on the circuit board gets like a dish of pasta when wired many number of wires because its insulator is tick.
- And changing a part of the circuit will be difficult.
- Working efficiency is not good, each wire must be stripped to be solderd.
So I recommend to use UEW for protoboard. The UEW is polyurethane coated copper wire which is used to inductors and small transformers. This wiring method is minor way, yet. However, it has cleard that problems, so that it is better way for wiring on the protoboard.
To wire with UEW, a wiring tool called "wiring pen" is used. The wiring pen is often sold with PCB kits, however, they are not useful because its tip is dull. When you did not satisfy bought wiring pen, it will be better to build it yourself. I built the wiring pen from a drawing pen.
According to some trial, 0.2 mm dia (32AWG) of UEW is the best for wiring the PCB. This is equivalent to 0.9 mm print pattern. Its insuration is sufficient for low voltage circuits such as a logic board below 20 volts.
It is very easy to wire in high density layout, even if parts are mounted on the board without free space.
Left image shows the solder surface. It is very smart because the insuration coat of the UEW is very thin. It will get like pasta if wire same circuit with PTFE wires :-)
This is a wiring pen that I built, wind a UEW to a bobbin and set it tail of the wiring pen, and wire in like drawing a line.
But Recently...
In early time, I had wired in avobe method that wire in wind-and-lead like daisy chain. However, it is not suitable for wiring random logic, analog circuit and surface mounted devices. To wire in point-to-point like wiring with PTFE wire is better for them. Now I am working in this method. The polyurethane coat at end of wire is weak in heat so that pre-soldering to the UEW without any stripping process is also easy. 350°C of tip temperture is recommended for UEW.
I am using only through holed protoboard, cut leads at solder surface to zero height, this can wire smoothly and can prevent to damage polyurethane coat by leads edge.
How to mount SMD
To mount SOP or QFP devices, most will use pitch conversion boards. However the conversion board is expensive and require mounting area, it is not smart method. Thus I am mounting that devices on the protoboard directly.
To mount the SMDs without pitch conversion board, put a polyimide (Kapton) tape on the board to insurate, bond the deivce on the tape and wire each lead. The polyimide is heat resistant material which is used for high temperture insurator, film cable and PCB. It can work up to 200°C continuous and resist soldering temperture. To solder wire and lead, pre-solder wire and lead, press wire to the lead with soldering iron, will easy.
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