I tin my wires prior to crimping...it helps to keep all those fine conductors to hold together when the connector is crimped on.

 

I’ve used that kind with success.

 

You can use a blunt punch and a piece of angle iron and duplicate that tool and get the same results. Unless you have a bunch of planned uses for the tool you can get great results with items similar to what I described. I have used my technique for years both on my stuff and when I used to wrench professionally. Good luck and show us your results.

 

Crimpin' ain't easy... I bought this at Lowe's and used it for a lot of projects, one of those "what in the world did I do before" tools? The soldering iron and the big torch aren't multi-taskers. https://www.bernzomatic.com/Products...r-Tool-BZ8360T

 

Well crimping is done. I got the one I pictured above for $13 and it did the trick.

 

Most excellent! Looks great!

 

I have to chime in on this one since I have 35+ years in the connector industry.

A proper wire crimp, done correctly is much better than a soldered connection. A little background on this. The crimped connector was invented and developed by Uncas Whittaker in the early 40's to replace soldered connections in WW2 aircraft. The USAAF discovered that the increase in electrical system complexity in aircraft with the associated increase in wiring containing soldered joints was slow to assemble and were failing quite frequently in the high vibration environment found in military aircraft. This was partially due to the skill required to properly solder a joint and variable quality among solderers in the assembly lines where anything but a perfect solder joint had a high probability of failing in the field. The crimp was developed to replace these soldered joints and was proven to be much more reliable, repeatable, and, most importantly, ideally suited to the mass production needed to support the war effort.

A good crimp is a gas-tight connection with fantastic long-term reliability. When a crimp termination is done properly, all the wire strands are cord-wooded into a homogeneous mass within the crimp and no strands are cut in the process. Pre-tinning is not required nor recommended and actually can be detrimental since it prevents this structuring of the strands in the crimp. The three main variables of a good crimp connection to be aware of are the terminal itself, the wire, and the crimp tooling used. Ideally, the terminal and crimp tooling should be matched to the wire since material thickness variation in the terminal can impact crimp integrity. This is compounded when a crimping die is used to crimp a terminal for which it was not designed for or terminated on the wrong size wire. An aspect of this to point out is that machine and plier-type terminations incorporate tooling that bottoms out when the crimping is performed to ensure a fully repeatable crimp when matched with the appropriate terminal and wire. Use the wrong wire or terminal and you get a bad crimp. The "whack-a-crimp" mentioned earlier that uses a hammer is a little more forgiving but runs the risk of over crimping that can cause cut strands and decreased current carrying capacity.

 

Given your decades of experience in the connector industry, I have a question that you may be able to answer. Is their any spec that relates the opening size of the connector to the number of strands in the cable to be connectorized?
I ask because these cables with a high strand count, ala welding cable, offer a new set of challenges over the heavier gauge strands.

 

There's few key elements to look at when terminating fine stranded wire.

Large gauge crimp terminals are often specified by a wire gauge size but are also specified by CMA (circular mil area) range they are capable of terminating. When selecting a terminal using CMA, it doesn't matter what the strand count is since you're basing the terminal selection based on the total cross-sectional area of all the strands. An added bonus us when using CMA as a basis for terminal sizing, you can combine multiple wires in a crimp since you simply adds the individual wire CMAs and then selecting a terminal that matches this total CMA. This document from TE shows how this is done.. https://www.te.com/commerce/Document...61_B.pdf%7FN-A

The second part of the large gauge fine stranded wire equation is the crimp used. The crimp configuration is the most important factor since you want to minimize cut strands. In my opinion, for fine stranded wire the hex crimp is best for this followed by a "W" crimp and lastly a single indent crimp. The hex crimp is the gentlest relative to fine strands.

Lastly, matching crimp tooling to the terminal is also key since, for example, a tubular crimp barrel from manufacturer A may have a wall thickness of 0.020" and a bore diameter of 0.250" ( resulting OD of 0.290") and one from manufacturer B may have a wall thickness of 0.030" and the same 0.250" bore diameter (resulting OD of 0.310") so when you crimp the B terminal in tooling made for terminal A, you may end up with an over-crimped terminal due to the thicker wall and an increased possibility of cut strands. The converse also can cause problems since crimping an A terminal in B tooling could result in a loose/incomplete crimp.

I should mention in closing that the reality is, that probably all our old trucks will not go through the abusive life they were originally designed for and used in. Our trucks are now typically sunday-go-to-meeting or ice cream run trucks so marginal crimps may very well be fine but if you have the option to do it right the first time, why not do it and prevent future headaches for yourself or someone else?

I hope this answers your question!

 

Thanks...good info! I use a hex crimper, it works especially well on cable with fine stranded conductors. That said, I still prefer to tin the wire first... I spent many years working on military aircraft and can appreciate a good electrical connection!

 

Lots of great info on proper crimping. I love that we have so many smart people on the forum. I would never have made it this far without you guys.