25-FEB-2008
A Tale of Two Crimps
OK I did one last experiment. This time I made a crimp with my Klein crimper/strippers and one with a my Ancor Products Single Crimp Ratcheting Crimper. I then cut the crimped terminals open with my Dremel tool and took a peak.
_
The crimp on the left was made with my Anchor Ratcheting crimper, which is a decent quality crimper, and the crimp on the right was made with my Klein dimple crimper, a very mediocre crimper, but also the type most boat owners use to make crimped connections.
_
I now understand why many boaters think "air" can get into a crimp and corrode it. If you look at he crimp on the right, made with the dimple crimper, you can still see strands of copper wire. The crimp on the left is far superior and has in fact cold worked or cold formed, into a near solid mass. While it is technically not a solid mass of copper there is almost no room for moisture or air to get in between the strands of wire and begin wicking. I think the photo speaks for its self and shows why a well built crimping too is worth the money..
16-FEB-2011
Crimp vs. Solder
This discussion has been beat around the net more than a tennis ball. I think the best statement on soldering a crimped terminal comes from the Senior Product Engineer Tom Michielutti at AMP. AMP is one of the most widely respected suppliers of crimp terminations to the US Aerospace and military sectors. Below is the statement from the senior engineer at AMP. NOT MY WORDS!!
_
Begin Quote:
_
"Subject: Soldering Crimped Connections & Solder in Crimps
_
This subject is discussed in AMP’s internal “Fundamentals of Connector Design” course.
Soldering Crimped Connections
_
In the minds of some customers, fortunately a diminishing minority, the reliability of crimped connections can be improved by soldering. In fact, soldering can degrade the performance of properly crimped connections. Such degradation can arise from the effects of soldering temperatures, the potential corrosion from improper cleaning of soldering fluxes and the effects of solder wicking on the conductors. Solder wicking causes the multi-strand conductors, which have high flexibility and stability against vibration, to become, effectively, solid which degrades both the performance characteristics mentioned. For these reasons, soldering of crimped connections is not recommended.
_
Should Solder be Used in Crimps?
_
Crimps are designed to work without solder or solder-dipped wires. Solder present in a crimp changes the deformation, metal flow, cleaning, welding, and residual force characteristics designed into the crimp. Soldering would be an additional heat producing assembly step. Test results show that soldering or solder-dipping wires before crimping does not produce a termination superior to that obtained in a properly applied crimped termination. Some tests specifically show detrimental effects due to soldering or solder-dipping (e.g. soldered crimp terminations can lose some ability to withstand vibrations and flexing, due to solder embrittlement of the copper wire, and/or due to
solder wicking up the strand of stranded wire to form a short length of solid conductor near the
termination). The terminated conductor then does not have the flexure strength characteristic of strand wire, and should behave more like solid wire which fails quickly in flexure testing."
_
The above is a direct quote from AMP...
_
The cut open pictured crimp was made with the tool on the left in the next photo. An AMP terminal and an AMP crimp tool certified for aerospace use. It will also withstand at least 190 pounds of pull out force.
19-JAN-2010
So, Which Crimpers Do I Use?
I actually don't use many of the crimpers shown in the body of this article, not that they are not good, but I prefer the crimps made with the AMP crimpers shown here.
_
If I am putting my name on a crimp only the AMP crimpers above will suffice to make me happy. Please DO NOT feel you need to run out and buy these as everyone has their level of quality that will make them happy, mine is obscenely high. These crimpers are used in the aerospace industry to make certified aerospace quality crimps. They can be re-built and re-calibrated by certified re-builders / re-calibrators and will literally last a lifetime.
_
The one on the right crimps blue and red connectors and the one on the left crimps yellow only. The AMP T-Head crimper on the right is part# 59250 and sells new for $1347.00. The one on the left is part # 59239-4 and sells for $671.00. They can often be found used through a rebuilder or recalibration specialist for a lot less money.
_
Before you can begin to complain about how expensive the Ancor crimpers are just think about what the ones I use cost me.. Wink!
