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Unread 25-09-2013, 08:35
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JamesCH95 JamesCH95 is offline
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Re: How does your team crimp terminals?

Just to demonstrate how easy it is to adjust ratcheting crimping tools, and that you don't have to spend a fortune on the tool or terminals to get good results, I conducted a simple experiment last night in my garage.

I took my $10 Harbor Freight crimping tool (that I think I paid $8 for), adjusted if for the horribly inexpensive wire terminal kit I also got a HF.



It took a few practice crimps and pulls to get it dialed in well, but it only took 15-30 minutes. According to this website, the mil-spec requirements for 10awg crimped wire connections is a 150lbf pull test. So, I figured out a way to do a reasonably accurate pull-test. I wrapped the wire tail through a link in my chain fall, grabbed the connector with a pair of vise-grips, stepped onto a bathroom scale (the same one we've used to weight robots several times!) and pulled until the connector failed. I just watched to see how low the scale read at the time of failure and subtracted that from my weight to arrive at the pull-strength of the crimp connection. I repeated it three times to ensure the results weren't a total fluke.

[note the appropriate attire]



Very near failure at 33.2lbs, I weighed in at 159.0lbs, so the crimp connector is sustaining about 126lbf pull right now.



All three pull tests results in failure at around 130lbf, with a spread of around 5lbf. Very consistent, and very close to the mil-spec strength of 150lbf. Not too bad for less than $20 for the tool and terminals.

For those worried about ensuring that terminals were sized and crimped properly: the ratcheting crimping tool imprints a number (or symbol) into the connectors insulation jacket. Mine imprints a dash or a dot, another pair my friend uses imprints a number. This makes is very easy to determine that the right crimping die was used in the proper orientation with a simple visual inspection. One just needs to see the number or symbol on the terminal end of the connector appropriate for the color (size) of the connector.



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