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Questions relating to designing PCBs
By peskywinnets
#161366
I've developed a a small electronic widget that I will be making initially by hand (well a CNC machine then hand soldering etc)...sales a likely to be very small (hence hand making!), I've had a slight change of heart wrt the latest spec, necessitating two individual wires join two small pcbs together (the two boards will only be 1"to 1.5" apart) ...the wire type will be something like 7/0.2mm hookup wire. The wires will not be colocated, but rather on different parts of the pcbs.

Now I know the correct way to approach 'wire to board' connections is to use a crimp connector, but this is a low cost product and the cost really goes up when involving crimp connectors (not to mention the extra labour overhead of crimping everything).

Once my little widget is installed, there'll be no stress placed on the wires at all ...so I just need the wir-> pcb csolder joints to absorb/survive the stress of the customer self installing the widget ...of course, there'll be punters who place very little stress on the wire solder joint & others who no doubt will place a lot of stress on the wire solder joint (ie as they move the wire connecting the two board about = stress on the solder joint)

So what I seek is some recommendations wrt the correct type of wire that doesn't place undue stress on the wire solder joint where it connects to the pcb ...I'm gussing that this is likely to mean using a really bendy/flexible wire type (because from what I can gather, wrt 'wire to board' solder joint, if the wire outer insulation is strong inflexible, then rather than the wire bending when the boards are moved during installation (thereby taking some of the stress), the stress is therefore placed on the wire solder joint...which can easily shear.

All top tips or wire recommendations warmly received?
By lyndon
#161372
peskywinnets wrote:Now I know the correct way to approach 'wire to board' connections is to use a crimp connector
That's only one of a variety of "correct" ways to do it. I use 26ga stranded wire in this application, specifically this stuff last time I purchased some. I usually solder directly to board #1 and use a header connection on board #2, but that's only to make it easier to assemble. When I began building the product that uses this connection, I just soldered directly to both boards.

As long as the boards are not frequently moving relative to each other or vibrating, you should not have any problems. I haven't ever had any issues relating to installation any time I've directly wired two boards together.