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caltermdeformed450.jpg

Some months back when Chuck mentioned a Storehouse brand assortment of crimp terminals, I commented that this was one place you really didn’t want to skimp on quality.  We all agreed this would be a good subject to test emperically, and I finally found the time to jump in and give it a shot. 

What follows is a test of three brands: Calterm (found at the local auto parts store), Storehouse (the Harbor Freight house brand), and some ETC terminals (which I can’t seem to find online) that I had in my toolbox from a previous job. 

The conclusion won’t surprise you, but there’s a twist that might.  Read past the jump for the skinny – plus oodles of pictures.


The Subjects

I selected blue 14-16 gauge terminals from each maker.  Since (unlike in normal use) we’re more interested in the crimp joints than the actual connector end, I used a different terminal type from each brand to make them easy to identify. 

Note: All the pictures in this writeup are courtesy of my craptastic $5 webcam which has great closeup capability but struggles with colors sometimes.  Also, that’s red heatshrink on the jaws of my “helping hands” alligator clip stand. The covered jaws don’t leave dents when gripping wire, and having some electrical isolation is nice too.  Click on small photos for larger ones.

storehouse1.jpg   calterm3.jpg   etc3.jpg

Pictured left to right above are the Storehouse, Calterm, and ETC terminals.  Inside each barrel, embossed ridges are visible; they help grip the wire when it’s crimped.  (I initially expected the cheaper brands not to have that feature, but it seems that they all do.)  The Storehouse terminal is, however, made from very thin metal while the others look much more substantial. 

storehouse4.jpg   calterm4.jpg   etc4.jpg

From the rear we can see more differences. The plastic shrouds on the Storehouse and Calterm terminals are just tubes, and the back of the metal piece is clearly visible. When inserting stranded wire, strands can snag on this ridge. The ETC shroud is molded into a funnel shape, which guides stranded wire into the crimp barrel.

nickedwire.jpg   smoothwire.jpg   crimperjaws.jpg

The Test

I used Calterm brand 14 AWG wire for all my tests.  To keep the playing field even, I discarded any wires that’d been nicked during stripping – like the one pictured on the left.  Each end was undamaged before crimping, as shown in the middle picture.  On the right are the jaws of the ratcheting crimpers.  These won’t let go until they’ve been through a full crimp cycle, guaranteeing that all the crimps are squished down to the (same) regulation size.

To put the connectors to the test, I prepared 3 short pieces of wire with a different brand of terminal on each end.  I then used the cranked up-and-down motion of my drill press to apply tension and measured the applied force with a competition fish scale. 

Read on to page two for our results and conclusions.

pages: 1 2

 

25 Responses to Test to Failure: Crimp Terminals

  1. Rick says:

    Awesome job Nate,

    Really puts things in perspective. Ultimately the storehouse stuff may be good for some things.. (cheap-o self tapping screws, zip ties, etc.) But it looks like quality is quality when it comes to the terminals. That said – have any good sources either online or Brick and Mortar for quality stuff at a reasonably price? I don’t see my self spending a small fortune at BlackBox (::link::) or something to get some decent terminals.
    Or do I really have to spend that much?

  2. Rick says:

    Just so you guys know the news isn’t all bad.. Found this kit with one of the ratcheting crimpers that Nate was talking about for $31 at Amazon ::link::.

    Made by Eclipse – not sure if that’s a good or bad thing.

  3. I’m happy with the Calterm results. They made it past the 65-lb mark with no problem, and if that’s good enough for NASA, it’s good enough for me. I’ll continue using my ETC stock for important stuff, but since I don’t know where to get more, I’ll be back to using Calterm eventually. The local auto parts chain has about 5 aisle-feet of their products, though I don’t ever plan to buy the craptastic hand crimpers. Actually, I should suggest that the store carry decent ratcheting crimpers, since once in a while, someone might realize that the extra twenty bucks is worth it.

    As for the Pro’sKit crimpers you found on Amazon, those look decent. I have one of their cable checkers and it works perfectly, though the fit and finish isn’t quite as polished as the big names. The terminals bundled with it might be junk, so be sure to test before relying on them!

  4. TimG says:

    Great test! I have only purchased the cheap stuff in the past. I’ll be sure to keep an eye out for the good stuff (have to find an easily accessible Canadian source though.. any hints guys?).

    That is always my trouble.. find great info on the net but it isn’t applicable to Canadians, doh!

    Tim

  5. Eric says:

    ETC is owned by Molex. you can buy ETC crimp terminals at digikey.com. From the catalog index under manufacturers, go to molex and click “Connectors, ETC, Crimp Terminals”. newark.com also carries them

  6. Ooooh! That explains why, pawing through my bucket of miscellaneous terminals, I have ETC of various odd sizes. Big Lots has $2 bags of assorted ring, spade, flag, bullet, splice, and even weirder terminals, and they say Molex on the bag. Mystery solved, and source identified! Now that I know where to get these things, I’m gonna pick up a few more of those grab-bags for the shop.

  7. nrChris says:

    Thanks for the great test. I always used the bargain outlet kits, never thinking much of it. Now I won’t skimp in this area–another item goes on the list for tomorrow’s Ace brown bag sale!

  8. Paul says:

    It might have been nice if you would have measured the thickness of the terminals for us with calipers or something. Debur first. Also, a bend to break test might have been nice too. That is how my crimp on connectors fail on me the most. Like put the connector in a vise and bend it back and forth until it breaks. Counting the bends until failure would quantify the strength of the metal the connectors are made out of.

    I know they’re called crimp, or solderless connectors, but I usually solder the wires into the barrels anyways. You can still make solderless connections with them after that. Even good ones corrode inside after long exposure. Solder helps a lot with that.

    Top quality connectors can be expensive. Not every application of them really warrents their cost for me.

  9. James B says:

    I determined my terminals were crrrap when I tried to solder them on with a blowtorch and they dripped off the end of the wire. While I can’t recall the brand, the terminals on the electrical aisle at Lowes seem more substantial. I’m getting ready to wire up an auxiliary fuse block for my 4WD accessories, and will look for the Molex made terminals.

  10. Taking suggestions for the next round of testing… ;)

    My fish scale’s only rated for 50 lbs and tops out at 100, so if I want to do ETC-vs-ETC testing or anything soldered, I’ll need to make a force multiplier/divider to expand the range.

    I can find a micrometer around here somewhere. Measuring the tongue thickness is easy. The barrel wall thickness is at the low end of my calipers’ range, but I’ll give that a try.

    I have a bunch of Sanchem NO-OX-ID around here, and while it’s not standard on compression connections smaller than 8 AWG, I’d like to try some pull-out tests to see whether a little grease in the joint significantly alters strength. It’s very effective at preventing corrosion, but I’m not equipped to quantify that effect.

    Soldering insulated “solderless” crimp terminals sounds like a recipe for smoke and comedy, but I’m game. I might even have some noninsulated ones around (aside from my regular Powerpoles), which would be fine to solder.

    Flexing would be a good thing to test, but might be awkward to set up in such a way as to get meaningful repeatable results. I’ll look into it.

  11. Chris S. says:

    i bought this cheapo harbor freight terminal connector set a few months ago
    http://www.harborfreightusa.com/usa/itemdisplay/displayItem.do?itemid=90279

    talk about garbage, the barrels are pretty hard plastic and the connectors are some kind of cheap tin. Half the time when i went to crimp them id go through the plastic. I was only using them to make some wiring mock-ups so its not like it mattered alot, but i was amazed how craptastic they were made.

  12. Rick says:

    Chris S.
    At $9.99 – it’s possible that it might be worth it just to get the little case that the connectors come in and just summarily dispose of them and get good ones to fill the cases. Or are the cases craptastic too?

  13. LucM says:

    For Paul or anyoe else that solders their ‘solderless’ connectors:

    A soldered connector will fail at a lower current than a crimped one, and may drip, or just plain fall off when it does get hot. Tinning the wire, then crimping is also not a great idea, as the crimp crushes against the soldered connection, wich can then change shape under high load, and fall out, or give you a high resistance connection.
    It is better to just get a real crimping tool, or switch to another type of connection if you feel the need to solder it.

  14. Crimping then soldering stranded wire is commonly regarded as a bad idea because the stiffened wire is more likely to fail under flexion. I do it anyway on terminations that I’m later going to reinforce with a few layers of heatshrink.

    Tinning stranded wire before crimping is, as LucM said, a good way to make sure the joint fails as soon as it heats up past liquidus temperature. It also wouldn’t accomplish much, as the solder would contribute nothing to the strength of the joint.

    Crimping then soldering solid wire shouldn’t have any disadvantages. The solder would prevent corrosion in the joint, and the wire isn’t any more likely to break.

    I have yet to experiment with NO-OX-ID and its effects on subsequent soldering. It’s mostly petroleum jelly, so I don’t imagine the smoke would be too noxious. Somewhere around here, I have a jar of Kopr-shield too, but I have no idea what’s in it besides copper.

  15. Pierce Nichols says:

    This is an excellent piece of work — I’ve sent the link to a couple of my co-workers to remind them why this kind of thing matters. :) I would love to see a test of the various grades of connector sold by McMaster. I’m currently looking at their crimp terminals with integral heat-shrink for some stuff my company is working on.

    As far as hand-soldering the connections go, just don’t. Good crimps are superior to solder for stranded wire as far as long term durability, especially under vibration, goes. The reason is because some of the solder wicks up the wire under the insulation and forms a stiff part. The wire then fatigues and breaks under the insulation, where the soldered part of the wire ends.

  16. Old Donn says:

    The above shoud read, Bravo HS.

  17. MissM says:

    I have found the same correlation with cat5 wire, RJ- connectors and crimpers. Its just not worth the extra time to redo all the connections. In a time of planned obsolescence, sometimes paying for quality does matter. :)

  18. Paul says:

    Craptacular Harbar Garbage update! So there I was this weekend in my fortress of solitude (my workshop) just innocently putting some drawers under my rolling bench. When at one point I felt the need for some wood plugs. Not a problem. I got the plug cutter kit, and a Harbor Freight Heavy Duty Milling Machine, which doesn’t make such a bad drillpress sometimes. OK, plug it in, switch it on, why isn’t it running?

    So I mentally shake my head and think, I swear I spend more time working on this junk than working with it. Now we get to where this pretains to this posting. This machine has one of those 50 amp style enormo plugs on it. You know the type? The ones you swear up and down you’re going to change all to twistlocks everytime you have to unplug them.

    Anyways I felt that was where the troubles lay with my machine not running. So I take it apart and sure enough one of the solderless terminals had come undone. The wire popped out in the classic failure mode. And then I remembered this posting. Ha-ha! OK I said I solder my solderless connectors, so out with the iron.

    First off I determined that the 3 foot of wire that HF supplied was a tad short. I have some SG cable lying around, I’ll use that. Then in the ultimate of cheaposity I decide to reuse the connectors! When you plan on soldering them this really isn’t that big a deal.

    I fight with that plug a lot, I really have to do something with the 220 line in my shop. It is one of those ongoing issues that I just haven’t dealt with yet but I know I have to. I need to install 2 more plugs and a disconnect. Til then it is plug and unplug 3 different things in one outlet.

    Well, this is the worst case scenario. Connectors in a high strain application. I’m interested in how well it holds up.

  19. Keith says:

    Guys, here’s the mother lode for terminals, crimpers, etc.: http://www.terminaltown.com/
    I do a lot of marine work, and these guys have everything, and all great quality. All nylon insulation, none of that crappy pvc stuff. They even have mil-spec connectors if you really want the best of the best. Most of their stuff is double-crimp, which means it crimps on not only the wire, but the insulation too, for a really strong bond. They have waterproof ones with adhesive lined shrink insulation. Check it out. No financial connection, just a happy customer.

  20. George Dalco says:

    I would like your opinion of taking off the insulation and soldering the connection after crimping and using heat shrink insulation.

  21. Well, you could just be using uninsulated terminals to begin with! Seems a bit silly to pay for the insulation then just cut it off. If you make a good crimp, the solder is somewhat redundant. On solid wire it won’t hurt, but on stranded wire it stiffens the wire and makes it less flexible. If you’re using stiff heatshrink, you might shift the stress point so that’s not an issue. Personally, I don’t see any problem with you plan, George. That sounds like a very strong joint, at least in tension. Flexion may or may not be a good idea, depending on how much solder wicks into the wire, and how much heatshrink you put on it.

  22. Alfred Geiser says:

    Nice test
    I’ve ben doing electrical work for more than 40 years and have always held that the T&B style crimp is better than the oval. The T&B has a round nest and a rounded tool that jams into it. The other has a slightly rounded nest on both sides. The T&B does spoil the insulation but it is indented and not a problem. It would be ineresting to see your type of test done on these two styles. AlG

  23. RALPH says:

    Crimping connectors on single strand, solid wire is a gaurateed failure. A Properly crimped good quality terminal is almost a weld as the strands are crushed together tight enough to form what is called in the electronics trade “gas tight” meaning hamful gaseses canot penitrate. Even the T&B dent cannot make a reliable connection to one strand sollid wire. Never use solid wire on a hookup that has any flexing. Copper is a material that work hardens with bending and will break in a short time with movement. A good source of terminals of good quality at reasonable cost is Ace Hadware brand. $8/100 nom and good variety availble. If you must have have a crimped terminal on solid wire and there is no flexig required use a soldered terminal. best connections for solid wire are wrapped clockwise under a screw head and tightend properly. Twist on wire nuts that use a somwhat flexible cover and inside tapered thread of diamond cross section spring wire so that tightend on the wire the wire thread and the plasticcover are some what expaned thus maintaining pressure on the wires. also the sharp edges of the thead wire will cut into the copper and prevent pull out. Hard plastic shell nuts will not allow the expasion or will crack or split if over tightend. The old 3 M soft plastic over a solid metal core with tapered thread are dangerous they will not maintain good contact over time. I have seen a great nuumer of these burned to a crisp, many on relativly light current loads like to a furnace. I will quit now. Anyone intrested in further discussion >Email rwringer@hoosierisp.com welcom.

  24. Henry says:

    You get what you pay for, even here in Australia. We’re using mainly Bosh and Tyco brand crimps and test every crimp tool in the factory once a year on a Mecmasin digital force indicator, what does not conform gets crushed so it will not come back and bite us in the butt. Crimp and solder is a no no as solder and flux wicks into the cable causing loss of flexibility and contamination by flux residues. Using flowable, non corrosive silicone on exposed crimps will graetly improve durability, specially on or near so called ‘sealed’ batteries. Some of our robots get submersed in brakkish water and we never had any problems except when they get hit by gun fire.

  25. Brian says:

    ETC is Molex branded terminals BTW. A little late to the party, but does not look like anyone knew. LOL…

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