keskiviikko 30. syyskuuta 2020

Crimp connectors


Crimped connectors are nice for production, but for hobbyist or even prototyping a real pain in the behind. While crimps and crimp housings are cheap, the tools to actually crimp them usual may cost several hundreds of euros easily. 

In this case I wanted to test a module which used Molex Micro-Fit type crimp, which I of course had not used before so I didn't have tools for it. Since I needed to make exactly one cable (to test that the cable drawing is correct before pushing it to production who have proper tools ready), I didn't feel like paying 150€ for tool I was going to need for just one connector.

Fortunately it is possible to "manually" crimp these by using suitable pliers. Place wire so that exposed part of wire is on inner contacts and insulation on outer and bend one side after other so that exposed wire is wrapped inside, and after that, bend outer contacts over insulation. Make sure that crimp contacts are properly wrapped around wire; if they point outwards, crimp will likely not fit in housing.


Here brown is ground that is in two places in connector, which is reason for ugly split there. And, again, this is one-off, for-quick-test-only cable so I didn't give a hoot about quality, only thing I was interested was whether designed connections are correct so that production can built it in volume without need of (expensive and annoying) rework afterwards.

You may want to also solder the wire to crimp too, to make sure that wire has proper contact. Only use just enough solder to make sure wire is soldered as a large solder glob will also prevent crimp insertion to housing. (above picture is taken before soldering)

A crimp made this way is way inferior to properly made crimp in just about every way, including but not limited to current handling capacity, mechanical reliability, aesthetics, and environmental reliability, so keep that in mind. 

This quick crimp job was nevertheless sufficient for me to test cabling (and yes, make corrections to drawing), and hopefully it will be useful for you too.