# what tool used to crimp this wire?

Joined Nov 21, 2018
814
Hi,
I have tool not work well.
Thanks

#### Lo_volt

Joined Apr 3, 2014
267
Those look like contacts made by a US manufacturer named Berg but they could be look-alike parts. Do you know the manufacturer of the contacts?

Most manufacturers sell crimpers intended for use with the contacts that they make. Have you tried contacting the connector manufacturer to see if they sell a crimper?

#### dl324

Joined Mar 30, 2015
14,462
I have tool not work well.
I use something like this:

It's hard to see from the picture, but each of the 3 openings in the jaws have two different crimp options. To do the connectors you indicated, you have to do 2 crimps. One for the wire, and another for the insulation. This is called SN-28B on Ali Express.

Your tool may have the same "feature", but I can't see it in the picture.

EDIT: these pictorial instructions imply the crimp can be done on the wire and insulation at the same time. I didn't find that reliable because the wire needs to be placed precisely to get a good crimp.

Notice that they didn't show the actual crimp because it's unlikely that all of the wire strands were in the crimp.

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#### ThePanMan

Joined Mar 13, 2020
367
It looks like you might have the right - or adequate crimper. Take one of the cut off crimped wires and insert it into the largest opening and then crimp down on it. If the crimper doesn't contact the crimp body then try the next smaller size. If that one doesn't seem to make contact then try the smallest one. If it doesn't make contact either then it is not the right crimp for that wire.

Crimping wires is just a matter of mashing the metal around the wire. HOWEVER, it's more a matter of crimping it in a way that it doesn't come loose. The crimp and wire should be matched so that you're not overloading the crimp body, sometimes called the crimp barrel. At either end of the crimp barrel there should be a "Bell Mouth", meaning a shape that leads into the crimp body without putting undue stress on the strands. The larger back portion of the crimp is the wire support. It usually holds the insulation tight without splitting it. However, there are times when it may look like it's loose. That has largely to do with the size (or thickness) of the wire insulation. Low voltage wiring often has thin insulation whereas high voltage wiring will have much heavier insulation. There's more to crimping than just mashing the metal.

One thing you don't want to do is tin the wire before crimping. Not unless you intend to reflow the solder AFTER it's crimped. Tinning before crimping can introduce more material into the crimp barrel than it is designed to handle, and can lead to fractures in the barrel. The wire may also become brittle and possibly crack. In all it's best to NOT tin the leads. However, soldering after making the crimp should pose no problem; as long as the solder doesn't wick into the crimp connection area or back into the wire. If solder makes its way into the contact area it can potentially jam the pin and break something OR it could bind the pin so tight that it's difficult to remove. Possible damage could occur when pulling a stuck pin out of a socket or vice versa. If solder wicks up the wire then the wire support crimp, the part that holds the insulation, solder could make the wire brittle and not allow it to flex. Fracture and failure are likely over some period of time, depending on how much movement the wire endures.

#### ThePanMan

Joined Mar 13, 2020
367

This crimper has an adjustment for calibration. Notice the small screw by the ratchet mechanism. You remove the screw and select one of the few detents it has. This controls how tight the jaws of the crimper close when making the crimp. In a manufacturing environment this sort of crimper needs to be calibrated for every use (daily). Weekly if all the same type crimps are going to be used. After calibrating the crimper a pull test needs to be done on the crimps. Depending on the size and type of wire and crimp there's a chart that specifies how much force the crimp must withstand at a minimum for pulling the wire out of the crimp. If it passes then the crimper is good to go.

Back in 2003 I worked for a company that made portable defibrillators. Being the new inspector on the job they kept me away because of what they feared would be a lack of experience. However, during flu season several of the inspectors were out sick and the crimps needed to be inspected. Upon looking at them for the first time I immediately stopped production. EVERY crimp could be pulled apart by pinky finger pressure. Using photo-micrograph techniques I took pictures of the obvious to me bad crimps and began teaching all the inspectors what to look for when inspecting crimps. I also trained the one and only person they trusted to make the crimps on how to calibrate and test the crimps EVERY MORNING before starting work with that or any of the other crimpers. To say the least that operator had no idea there was even a way to calibrate or a need to test.

My work went all the way up to the regional quality control manager who had to issue recall notices on over 4,000 units. The crimps were so poorly made they could easily vibrate loose bouncing around in the back of a police cruiser. The last thing anyone wanted was a failed unit when someone's life depended on it. Now - guess who got laid off! Corporate learned that I was doing the training and they assumed I had been working there years and failed to catch the error sooner. But who wants to work for a company with their heads up their crimped winky's.

#### dl324

Joined Mar 30, 2015
14,462
This is the detail I couldn't see from your picture, or the one from Ali Express:

One side is for the crimp on the insulation and the other is for the wire. I could never get a satisfactory crimp on the wire if I tried to do both crimps at the same time.

EDIT: I guess I remembered incorrectly. I just tried making a crimp and was able to do wire and insulation at the same time. I think my problem before was that I was trying to do 14 crimps on a ribbon cable without separating more than the last inch or so of the wires.

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#### ThePanMan

Joined Mar 13, 2020
367
One side is for the crimp on the insulation and the other is for the wire.
In this picture the near end is for the wire support crimp. It's characterized by a larger crimp port.

And yes, you do the entire crimp in one Feld swoop.

#### dl324

Joined Mar 30, 2015
14,462
In this picture the near end is for the wire support crimp. It's characterized by a larger crimp port.

And yes, you do the entire crimp in one Feld swoop.
It also seems that the jaws were installed upside down. I had been holding the tool "upside down" so I could see how the wire was positioned in the connector. It's much more convenient with the jaws installed like the OP's tool.

#### sagor

Joined Mar 10, 2019
695
I use a similar crimp tool (SN-28B). Works great for KF2510 connectors, but not JST SM. At least not the female pins. The male pins seem to crimp ok, but the female ones are totally deformed. That said, the pins are from a Chinese source, and don't seem exactly the same as those specified by JST themselves. Real close, but not exact.
So, it is a bit of a crap shoot. I ordered a PA-09 tool (similar to IWS 2820m), which does one of the crimps at a time . That is, you have to crimp twice, once for bare wire, once for insulated part of wire. Also, the PA-09 tool has different spacing/hole designations than the SN-28B, and more of them. That lets one adjust the crimp based on insulation and wire thickness, I assume...
There is a lot of different tools and connectors out there, most of them from off shore sources. Quality may be questionable on some of those items. If you get something that works, fine, use it. Otherwise, you need to try different tools and different pins to find a proper match.

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#### dl324

Joined Mar 30, 2015
14,462
I think the kit actually costs half as much as just the tool itself which was a bit of a shock.
$68 is a bit much. I bought something similar from Jameco that would do 3 different sizes for about$20 $10. The ratcheting crimper I mentioned earlier was about$20. It was definitely worth the price.

Tool from Jameco:

I bought this tool to do red and blue flag terminals. Also for about \$20.

#### geekoftheweek

Joined Oct 6, 2013
815
I also have a snap on and iwiss with interchangeable jaws, but I still like the Molex the best. None of them do the weather pack seal crimps right, but I don't do enough of them to make it worth finding one at this time.

#### SamR

Joined Mar 19, 2019
4,194
Which are the correct jaws, SN-28B or SN-2? I've been using the 28Bs and not particularly pleased with them. Upon further investigation, it appears they should be the 2s? I've seen both advertised for Dupont style pins.

#### MisterBill2

Joined Jan 23, 2018
11,880
I am familiar with at east four rather different kinds of crimped connections, and mostly none of the crimpers are able to crimp other styes of pins very well.

At the bottom of the list are the "champ" style crimpers that usually also include a wire stripper and screw cutter. They simply mash a round barrel connector down on a wire for a short distance, often providing an adequate connection, but not always.
Next is an improved version crimper that produces an indentation along the round barrel axis, squeezing the wire strands against the sides of the barrel. This style produces good crimps when used with the correct terminals for the wire size.
The connectors in this discussion seem to be the third type, for "F" style lugs that have two tabs that fold down over the wire, wrapping around the strands, and two more tabs that fold over the insulation to provide strain relief and preventing flexing at the crimp. These crimpers require that the two sides be the correct size for the terminal being crimped. These are different in that the wire is placed down into the connector rather than sliding into the end of the round barrel, which makes correct assembly easier. These crimpers are much more expensive than the first two types.
The fourth type of crimper is mostly used for insertabe connector pins and sockets, and squeezes in from four sides of a barrel to capture the conductor strands with a controlled amount of crushing. (These are the connector pins and sockets that may also be soldered if no solder is left on the outside to interfere with insertion in the connector body.)

#### ThePanMan

Joined Mar 13, 2020
367
It also seems that the jaws were installed upside down.
That's something that has never cross my mind, swapping upper and lower jaws based on the way you hold the tool. I have a standard ring terminal type crimper with plastic jacket that I'm always fussing with in order to get it into the tool properly. I'll have to look into whether I can swap the jaws around. If so - - - great suggestion. Thanks.
you have to crimp twice, once for bare wire, once for insulated part of wire. Also, the PA-09 tool has different spacing/hole designations than the SN-28B, and more of them. That lets one adjust the crimp based on insulation and wire thickness, I assume...
This makes sense as you "assume". Low voltage wiring will have a thinner insulation and with a large insulation support crimp - it can be rather loose. Having the option to back crimp the insulation support on larger or smaller insulation diameters makes sense. I think it's a safe assumption.

#### dl324

Joined Mar 30, 2015
14,462
I've been using the 28Bs and not particularly pleased with them.
The SN-28B I posted works fine for Dupont connectors. That's what I bought it for. It also works for some other connectors I happened to have.

#### SamR

Joined Mar 19, 2019
4,194
FWIW most of those tools are made in china so can be had much cheaper buying from AliX instead of a US reseller. If you're willing to wait on them...

#### Ya’akov

Joined Jan 27, 2019
5,660
I use this iWiss tool which has good dies for "DuPont" connector pins. The trouble is that DuPont connector doesn't mean one thing, though in general what we call DuPont connectors came from "Mini-PV" connector by Amphenol, that were copied in a cheaper version by Berg, that became DuPont Connector and that's the name that stuck.

In any case, the trouble is the connector was designed to have a round crimp and only the very expensive commercial tools do that. So, you have to find a tool that doesn't spread the the crimped part too wide. Most of the cheaper tool make them far to flat to fit properly The iWiss does OK if you are careful and use the right die size. This is often the cause of a lot of trouble. On the iWiss tool the proper choice is the 1.6mm die, the third one over. I find I get quick and repeatable results with this tool and I like the vertical orientation, I find it easer to work with.

#### MisterBill2

Joined Jan 23, 2018
11,880
There is another alternative that I have used, for round pins that were intended to use the 4-point crimp. That is to solder the wires into the pin. It does require not leaving any solder on the outside, but it works very well. That allowed repairs when there were no replacement connector pins available and no time to go and get them, and the crimp tool, if they were available. And the damage to the cables was always outside the connector so there was always enough wire to pull the broken end out of the pin. Of course those folks with poor soldering skills were indeed Out of Luck.

#### ThePanMan

Joined Mar 13, 2020
367
Surprised this isn't more expensive: