charging deep cycle battery

[Joe917]

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.

For more details and photos:
http://www.pbase.com/mainecruising/wire_termination&page=1
http://www.pbase.com/mainecruising/battery_cables

 

[4x4junkie]

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.

A very biased source indeed (and runs completely counter to what my experience has been for decades).

Perhaps with extremely high dollar aerospace components (on aerospace-grade wire) it might be different (though I've no desire to go broke finding out), but anything at the consumer level I know for a fact crimps suck (infact just this weekend I had another one develop resistance and burn up in our RV).

 

[AndrewP]

I don't think it takes Aerospace components. It takes a good crimper. Every OEM on the planet crimps only.

Even at the consumer level, these rarely fail, and theoretically are more resistant to the effect of vibration.

But for the quick and dirty/limited tooling/expedient 4x4 world we live in, either method done well will work fine.

Me personally, I think the effect of good strain relief is overlooked, and so in almost all cases, use the heat shrink style terminals, with a crimper made for heat shrink terminals. And, BTW, if you are not using ratched style calibrated crimpers, you aren't doing a good job.

Decent discussion here:

http://www.pbase.com/mainecruising/wire_termination

This "Compass Marine" site is full of hints and tips that apply to the 4x4 world, worth a bit of your time on the electrical articles.

 

[AndrewP]

What is Consumer Level anyway ?
(Overall, I think its something to do with the General Public what thank goodness I am not a member of...)

Perhaps its 4.99$ crimpertool & box of 1000 assortment terminals what Harbor Freight sells a container ship full per week ?

Consumer level-like your car, my car and almost everybody's "expedition vehicle". The factory electrics are crimped.

And you seem to have completely missed the point of my post and chose to focus on 2 words which you misconstrued. To make good crimps, crimps that will last as long as you need them, you need the proper crimper. Not the garbage "crimper" they sell at the hardware store (or walmart), or worse, a set of pliers or vice grips.

And now I'll misconstrue your post: If you're buying your electrical supplies at walmart, well, good luck.

 

[chromisdesigns]

Just solder battery cables

You should really just solder battery cables with a good quality silver-bearing solder, paste flux, and a torch. To get a reliable crimp on large cables, you need to use a hydraulic crimper, very $$$ unless you can find someone who will lend you one.

OTOH, with a plumber's torch and shrink-wrap sleeves you can make reliable connections that should last for decades.

Save the crimps for small gage wire, and for those, do use a proper crimping tool, not pliers.

 

[4x4junkie]

I don't think it takes Aerospace components. It takes a good crimper. Every OEM on the planet crimps only.

Even at the consumer level, these rarely fail, and theoretically are more resistant to the effect of vibration.

I guess it must be interesting then that the vast majority of connections I've had fail are infact ones provided by an OEM... The one on our RV last weekend was right where a wire was crimped to a terminal going into a fuseholder, same thing again about two months ago an ATC inline fuseholder for the driving lights on my BII roasted itself after one end apparently developed resistance in the internal crimped connection. Maybe this is all just bad luck going back three decades? Whatever the case, this problem never seems to recur when a connection gets soldered, so I'm not sure what else to say here...

 

[AndrewP]

I guess it must be interesting then that the vast majority of connections I've had fail are infact ones provided by an OEM... The one on our RV last weekend was right where a wire was crimped to a terminal going into a fuseholder, same thing again about two months ago an ATC inline fuseholder for the driving lights on my BII roasted itself after one end apparently developed resistance in the internal crimped connection. Maybe this is all just bad luck going back three decades? Whatever the case, this problem never seems to recur when a connection gets soldered, so I'm not sure what else to say here...

Obviously, I don't care how you put wires together, only pointing out that crimps are perfectly good practice. If the wires vibrate at all, well done crimps are superior. If you think about your Bronco2, it's 25 years old and has maybe 500+ crimped connections. The fact that only one has failed is a pretty good track record.

 

[4x4junkie]

Well, you do make a good point.
I got to thinking about that after I posted... I think a difference may be that the connectors automakers use have silicone rubber seals where the wires exit, which keeps the crimp inside protected from the elements. Many of the connections I've had fail indeed were ones not protected in some way from dirt, moisture, etc.

 

[Ducky's Dad]

Weatherpack-type connectors are available at some electronics stores, but are pretty scarce at auto parts stores.

 

[Scoutn79]

With regards to this thread I got curious, so I did some testing.

I did this years ago to verify my method works, but this thread had even be doubting it.


Test as follows...

Found an old battery cable in the shop. So I lopped one end off of it, and found the correct lug in my electrical drawer.
I think it is a 1/0 cable. Not sure, doesnt really matter.

For the sake of the test, I did as MOST probably would, not knowing any better.

Zero prep. No wire wheel, no flux, no nothing.


here we go...

With lug in the vise, I stripped the cable and test fit.

Satisfied with the fit, I loaded the lug with some solder and added heat.
This continued until the lug was about 3/4 full, and completely molten.

Then the cable was inserted, heat applied for a few more seconds, then heat removed and assembly allowed to cool.

Interested in how the solder interacted with the strands, I pulled hard on the insulator to see.
Its hard to see in the photo, but the solder was bonded to the strands, and looked to go pretty deep into the cable.

After everything was cooled the connector was crimped, using nothing more than a "hammer" type crimper.
I find they work very well with large conductors.

Now, this is where I would normally install the adhesive heat shrink, but instead I cut the joint apart for inspection.

Right at the end of the lug, just about where the conductors ended.
Even though everything is coated in solder, the voids remain. This is why many will drill a small hole into the lug, to allow the solder to flow into this portion.

Although, with the conductor ending right here, I see no harm in not having solder.

Then I cut right thru the crimp joint.

This is what I referred to as "cold welded"

The copper strands, solder, and copper lug are literally 1-piece due to the compression of the crimp.

Then I cut right near the entrance of the lug.

Same story. 100% void free and cold welded.

Thoughts??

I still fail to see the reason to NOT utilize this method.

Interesting test but not at all a good comparison of the two methods.
You did a proper crimp with an expensive, properly sized tool but did a half a$$ed job soldering (as you mentioned)
Most people will have solder but very very few will have to proper crimp tool.
I believe people are much more likely to use flux to solder and a hammer/chisel, pliers, vise etc to try and crimp a wire that large.
I use the solder method on all my heavy cables and critical smaller wiring all finished off with quality heat shrink.
I like the heavy lead clamp battery terminals that come with a solder plug that you drop in the end heat to melting then insert your pre-fit cable. I get mine from NAPA but I am other places sell the same for less $.

I would like to see these tests performed on both of these methods when properly done.
1) pull out test
2) corrosion test

Darrell