Sunday, 30 October 2011


After a few days, my new crimping toys tools arrived in the post. Here's a joint from a couple of years BC (Before Crimptool) :
First attempt at crimp connectors
However, that was before the RVFM HT-225D, which I got from Rapid.
It has the correct 'B' shaped jaws to make proper crimp joints:
B-shaped jaws
To use this effectively, you need a set of crimp pins, and you need to carefully strip and trim the wire, like this :
Trimmed wire
Then you need to insert a crimp pin into the appropriate jaws - note you don't always need to remove them from the strip, I found them easier to handle by bending a single pin away from the strip.
crimp socket inserted
Then, insert the wire : I marked a small dot with a sharpie to mark the appropriate depth:
Ready to crimp
Pull the handles together until they're all crimped - rinse and repeat:
four pins in two minutes
So much easier and more efficient than the manual pliers/solder method. They're not 'perfect' yet - according to the spec I've got a little too much insulation in there - but it's a damn sight neater than my first attempts a couple of years ago :-).
Completed Plug :
Completed plug


Nudel said...

Nice guide! I have used my crimping tool a lot on my RepRaps, and I'm really glad I got one.

Just make sure you test the quality of the crimps by pulling the cable. Wouldn't want it to get loose.

Some people solder the crimp as well, which is a good - though perhaps a bit excessive - precaution.

Renoir said...

Agreed - a quick tug is needed just to confirm it's all secure.

I read somewhere that Molex (who produce the connectors) say that the crimp joints should not be soldered - they are not designed to be : But, if you really have to, then tin the wire *before* crimping, and then just re-melt the solder after crimping in the crimping joint - do not add any extra solder.

I suspect it's because it's too easy to melt the insulation and/or mess up the connector end if the solder flows along the pin.

Renoir said...

I found this :

Looks like it might be worth a punt if you're looking for a cheap crimp tool - £13.45

Jeff Keegan said...

Nice! Always glad to see someone explaining this.. I too suffered through BC (before crimptool) days, unaware of how much easier my life would be with a proper crimp tool.