Crimper Shoot Out / Load Test Results

For a long time I have known that well made crimps, with the right tools, are electrically very good, and strong. I have an analysis/white papper done by the US Military with Martin Marietta Corp that goes into great detail about just how reliable crimps can be.

Over the years I had used weights to test my terminals against the available tensile force standards. I test my tools and terminals periodically to know they are performing at the level I expect. In short the tensile strength of a crimp directly corresponds to the electrical quality.

To minimize any of the Doubting Thomas types I decided to video this process rather than photograph it. You should know that I really suck at video and I apologize for the sniffles in the videos but I had a cold during this process. The videos are unedited and taken straight from my P&S camera and loaded into Picasa 3. The only thing I changed was to clip some of the beginning and end of each video to cut down on upload times. The camera shoots in HD so my upload times were very, very long.

Some of the results are rather alarming. On the crimps that consistently failed at or below ABYC minimum standards I made multiple videos. Even with the cheapest crimpers I occasionally hit the required ABYC bare minimum BUT these were NOT repeatable results and the next crimp done the same way could have, and did often fail in the single digits or in the teens. The videos show the wire stripping, crimping and pull test until failure all complete and unedited.

Test Procedure:

12GA Wire > Yellow 10-12 Insulated Terminals

In all these examples I am testing 12 GA UL-1426 marine grade tinned wire by Berkshire. The terminals are double crimp insulated made by Ancor. I only chose Ancor because that is what many boaters tend to use. It should be noted that I DO NOT use Ancor terminals due to grossly inconsistent supply. I use FTZ & AMP because they are always CONSISTENT! I only use Ancor terminals when in an absolute pinch. Keep in mind that Ancor does not make these terminals they simply repackage them from what appears to be the lowest bidder (this assumption based on inconsistencies).

I thought it was important to test the smallest wire size designed for the terminal. If there is going to be a bad connection or weak connection it would show up more easily in a 12 GA wire inserted into a terminal designed for both 10 GA & 12 GA rather than the larger 10 GA wire.

With AMP PIDG terminals & the AMP crimp tools mated together I often break the wire first....

The ABYC minimum recommendation is for these terminations is to hold 35 pounds tensile force.

WARNING: I DO NOT agree with the ABYC E-11 tensile strength standards and find them pathetically low. It should be noted that the Mil Spec MIL-T-7928 tensile requirement for this same terminal is actually 110 pounds!!!!! I use MIL-T-7928G for my own tools as my baseline/bare minimum. You need to choose what you are happy with..

The ABYC's 35 pounds is pathetically weak in comparison but it is what it is. I personally want to beat MIL-T-7928G NOT the ABYC requirement. I strongly suggest aiming for MIL-T-7928G not ABYC E-11 standards.

Tensile force was recorded using a calibrated digital load cell. All terminals were pulled to failure.


Standards:

As you will see not all crimper tools are created equal and the performance is markedly different. Interestingly enough in this testing the tensile strength held corresponds directly to the cost of the tool so sometimes you do get what you pay for. This is likely just luck of the draw..

Crimpers are shown in order of performance.

Only two crimp tools hit or beat the Mil Spec MIL-T-7928G standard and those were the Ancor and AMP tools.

Here's a chart that breaks out varying standards including MIL-T-7928G:


Please keep in mind that this test is not really about how much it takes to pull the wire out, though it may appear to be that way. Your wire & terminal should NEVER even be subjected to 5 pounds of load on a boat let alone 190 pounds +. This is just how crimp testing is done and performed by all standards organizations world wide.. This is how the Aerospace and Military rate crimped connections along with other measures such as salt spray, vibration, heat, voltage drop and amperage tests.

When researching this the engineers I spoke with at Tyco/AMP, Molex, Rennsteig etc. suggested that the amount of strain required to pull a wire out of a crimped terminal is in direct correlation to the quality of the electrical connection made when crimped. A higher pull strain reflects more wire to terminal surface area interaction and a properly formed crimp that will be near air and completely water tight (gas tight is the industry term) will have a very high pull out number in pounds of force required..

A low pull failure number means little wire to terminal surface area interaction and paths for air & water to migrate up through the crimp and begin corroding the wire.


Video Tests:

Video Set #1 - AMP 59239-4-P - This is the benchmark industry gold standard tool for yellow terminals to which all the others are judged. With the Ancor terminals it holds into the 190's and occasionally over 200 pounds!

This crimp tool is aerospace/aircraft grade and carries an aircraft industry certification. Before changing my knot, I tried a Bowline, the wire failed before the terminal every time. This is an obscenely priced crimper but If I am to put my name on electrical work this is the tool I use for yellow insulated terminals. There is a second tool for blue & red.

Overkill? Probably but I sleep well and I do enjoy finely crafted tools. The results of this tool are more repeatable than any of the other tested tools and often times the pulls resulted in only 1 or 2 pound differences at failure. In this video it holds to 193 pounds.


Here's a second video of the AMP showing me holding the applied load longer to see if that would change the pull out numbers. It only changed by 1 pound 193 Lbs. vs. 192 Lbs..



Video #2 Ancor 701030 Double Ratchet Crimper - Held to 126 pounds. For the price this tool comes the closest to the benchmark tools I've tested, on standard double crimp insulated connectors. The jaws are beautifully machined and the crimp band surface are is wider than the Harbor Freight or the Pro's Kit tools. This well made tool is the performance / $$$ winner holding 126 pounds and doing so on a somewhat repeatable basis.

EDIT: Please note that I tested a recent example of the Ancor double crimp ratchet tool and it tested slightly below than the Pro's Kit tool. All I can assume is that Anchor changed vendors or cut quality to make more money. The recent tool I tested was NOT the same tool I tested in this video though the model number was/is the same.

It should be noted that all the cheaper double crimpers close the jaws like scissors. Because of this, repeatability can get skewed unless you can load the terminal in the exact same way every time you load it. If the terminal is twisted the results can change 20 pounds or more. With any crimp tool you need to practice your crimps. For all these tests the terminals were installed into the crimp dies as close to vertical as I could possibly eyeball. The AMP tools close like a Guillotine or drop forge, not like scissors, and thus repeatability is far more accurate.



Video #3 Pro's Kit CP-371 & 9CP-236DH Crimp Die - Held to 91 pounds. This tool was recommended over on Sailnet by a member there so I bought one to try it. Keep in mind that this is more than 100 pounds off the AMP benchmark tool but still well above the ABYC suggested minimum. It also exceeds many of the above "standards". It won't beat NASA or Mil Spec or SAE but for the money makes a decent crimp..

Because it has easily replaceable crimp dies, which don't cost a lot of money, you can get both a single crimper for heat shrink, and a double crimp die for standard insulated terminals, all for about $50.00. You can also buy coax and many other dies too. While the Pro frame is well made it requires more force to make the crimp than does the Ancor crimper and the ergonomics are simply awkward to me. While it produced a very respectable amount of pull resistance for the money it was bested by the Ancor tool, by 35 pounds, on a regular basis. The dies are not as well machined and the crimp band surface are is narrower than the Ancor tool. This is probably where the tensile numbers differ. A thinner crimp band clearly seems to correlate to lower holding power.



Video #4 Harbor Freight 97240 Double Ratchet Crimper - This particular tool is a very, very good value. It held to 83 pounds of pull and for $15.00 is a far better choice than ANY of the cut, strip, crimp toys that are out there. Please be very careful with my statement of "value" and don't take it as a flat out recommendation. Please take it with a grain of salt. While I happened to get one that works OK, you may not.

I have two of these crimp tools sold under the SAME Harbor Freight model number that are completely different. One has machined crimp dies and one has cheap plates of stamped steel. HFT is always changing their specs and manufacturers so the tool you buy with the same part number may not even be close to the performance of this one. While the tool works it's sloppily built, poorly machined and overall rather poorly executed BUT worth about the $15.00 it costs. I would urge anyone looking for a good value to buy the Pro's Kit tool instead. This one turned in a decent performance, it held to 83 pounds, but will they all?? I can't say and won't as I have been burned by Harbor Freight far to many times to trust them....



Video Set #5 Klein Cut/Strip/Crimp Tool - Another cheap tool producing horrifying results that were all over the map. In one pull I hit 42 pounds but out of 20 terminals and 20 crimps this was the only time it bested the minimum ABYC standard of 35 pounds, the only time. The results were not at all repeatable and I saw failures from 3 pounds to a high of about 29 pounds if you threw out the 42 pound result as a freak incident. This tool literally busted my hands just to hit 27 pounds of pull out force which is still 8 pounds shy of the bare minimum, a bare minimum which is pretty pathetic..

In the videos you can very clearly see how much pressure I am applying. I even pressed the handle against the workbench for leverage and you can hear the plywood crushing and see the dents. The results were not because I am a weakling, trust me.. This tool is flat out dangerous as far as I am concerned because the results are far from repeatable. In many instances the crimps split the brazing on the crimp barrel allowing it to collapse out of unison. That is NOT supposed to happen when you crimp but when you use the wrong tool for the job it can.

Video A - Fails At 12 Lbs.


Video B - Fails At 27 Lbs.


Video Set #6 - El Cheapo Cut/Strip/Crimp Tool - In these videos the crimps are made exactly as they should have been and failed far to early. I am squeezing so hard in some of these videos that you can see the frame of the tool bend and rebound. The only place on a boat for a tool like this is with Davey Jones!

Video A - Holds To 16 Lbs.


Video B - Holds To 3 Lbs.



Video Set #7 - Human Tug Test - I wanted to do a video to show what I can exert on the crimped fitting by tugging on the wire. Keep in mind I had the unfair advantage of holding an eye bolt on the load cell and the terminal in the other hand. The most I got to was 21 pounds and it left a darn good mark on my finger doing so. I then compared this to what I used to do my pull test at and found out I normally applied less than 10 pounds of force doing this check. Bottom line is that unless you are Hercules, and your fingers made of steel, the human tug test tells you little to nothing unless you are using a dime store tool that regularly fails at or below 10 pounds. If you are using a proper tool the "tug test" is all but useless.

Video A - Strip, Crimp & Tug Test


Video B - After tug test it holds to 32 Lbs. (a record for this tool)

 

Re: Fun With Toys..

You HAVE "cheapo tools"? I'm shocked!

 

Re: Load Testing Crimp Terminals

get back to shoveling snow!

Can't wait for your anchor pull tests...

 

Re: Load Testing Crimp Terminals

This makes me wonder what I am doing wrong when I crimp wires. I often get results that will not survive a moderate tug on the wire.

 

What tool are you using and what crimp terminal?

 

Re: Load Testing Crimp Terminals

will you be testing battery cables and terminals as well ..that would be kinda cool to know...thanks...

regards

woody

 

If MS is in need of cheapo crimpers I can send him one of the several I've bought over the years and which yield the result that Higgs describes.
I've used the Heat Shrinking terminals available at WM.
I'm looking forward to an upgrade.

 

Oh, I've got some cheap ones.. Check out the yellow handle ones on the left...

From L to R: The Stripper, Klein Cut/Crimp/Strip, HFT Double Ratchet, Ancor Double Ratchet, HFT Double Ratchet (steel plate dies), Pro's Kit Double/Single Crimper, Ancor Single Ratchet , AMP T-Head (Blue & Red Terminals), AMP (Yellow Terminals)

 

I don't know the brand name, but it is one of those tools that strips different gauges of wire and also has crimping slots at the tip.

 

Re: Load Testing Crimp Terminals

Although this testing is certainly interesting, wouldn't a proper installation mean supporting the wire and the device it's connected to independent of the terminal? That's a code requirement in the electrical trade and when I rewired my boat it was the standard I followed. That is, no stress on the connections (terminals).

 

Re: Load Testing Crimp Terminals

I'd suggest stripping the wire at the anchor point so you're not picking up anything from the insulation.

 

Why would I want to do that when that feature is an integral part of the design of a double ratcheting crimper? A fair comparison is the total strength the crimper will impart as it is intended and designed to be used. That being said I will insert a wire and only crimp the strain relief portion to show what the jacket holds. I highly doubt it will be much more than 5-10 pounds, if that..

 

Because the far more common and cheaper crimpers bear only on the wire. I acknowledge anything added by the insulation will be minor.

 

With the Ancor double ratchet crimper it held to 8 pounds...

 

Re: Load Testing Crimp Terminals

Maine, instead of knotting it, why not crimp both ends, one to the bench and the other crimped terminal to a block and do a straight pull? Your dealing with less than a 250 lbs load so you should be able to get a block small enough to fit through the eye of the terminal.

Love the new toy and can't wait to see all the experiments with it.

 

Re: Load Testing Crimp Terminals

MaineSail,

My crimpers aren't HALF as good as your yellow ones.

Hey, do you suppose those ring terminals could be used for standing rigging??
Kidding!!!! Geessss!

We're getting another bout of the white stuff on Wednesday. I wonder how Tim is making out.

 

A few thoughts (always a problem, I know)....
* Assuming the ratchet crimpers were all adjustable for fitting brand, did you adjust them to some sort of baseline?
* Did you take all of the non-ratchet crimpers and heave them off the dock? I pitched mine, to remove all temptation to use them "just in an emergency." With my weak hands (carple tunnel) I doubt I get much over 6 pounds pull-out, since I often could tug them apart. With the ratchet crimper, as you say, when they pullout it is generally with signifigant damage.
* It would be interesting to test some solder-only fittings and some solder-only fittings with some heat (say, boiling water). I don't know the result. I think we all solder on some occations.

Great posts. I know it is work.

 

Yep - that's them. My palm aches just looking at them.

 

The Pro 's Kit Double/single looks ergonomically like the easiest to use. What are those jaws sitting by the handle? I'll be watching the crimp results to see how that one does.

 

Re: Load Testing Crimp Terminals

Great stuff..
Now time for the Wheatstone Bridge to see what they do electrically !! Just kidding, Maine..