Crimp Tools

I have been looking into Crimp tools lately. I have a cheap crimper, and I've been frustrated by how lousy the crimps are. They pull out, the pins are crushed, they do not fit into the sockets well, and getting them out is near impossible. If you do get them out, the housing is so damaged that using it again is just asking for trouble.

None of these matter much if your just "messing around" at home. However, what if you want to do some things that are a bit more professional, and perhaps even sell a few items? Having a lousy crimp job is asking for trouble, taking a risk that your customers might be dissatisfied with the product - i.e. a wire pulls out - what are they going to do??

So, I started looking at the Molex web site, and even contacted their tech support. As it happens, I would need Three (3) tools to handle the pins I have. Now, each of these tools lists in the high $200 range ($269 at Digikey). Ouch. But, are they worth it??

I am what I call a "Lazy" engineer. I know some engineers that will spend a great deal of time "finding a way" to avoid spending that extra money. Me, I'm more in the camp that if I can spend a couple hundred bucks and save myself a lot of hassles, I'm into that. If I can grab the crimper, make a clean, solid, trustworthy crimp every time, plug it in and then I'm off and working on something far more interesting... then that has value.

On the flip side... I don't like to spend money if there are other "good" or acceptable solutions to a problem like that that do NOT require spending large amounts of cash.

The Question - what are some other opinions on this? Spend the money, get the best tool and just KNOW that you are doing a great job... and, have some confidence that if you do sell something, you are selling a quality product??

Oh - regarding the "three" tools, I found that it will be cheaper to "consolidate" my pins than it would be to go and get 3 tools. Also, Molex does have a "low cost" universal too.. At this point, I'm thinking of getting two expensive tools for two different types of pins (Micro Fit 3.0 and CGrid), and then the universal too for the large gauge (which normally requires another tool).

Thoughts??

I found this link. Very nice info. Talks about what makes a good crimp and what makes a bad one. The tool I have is definitely in the "BAD" category.

http://www.pinrepair.com/connect/

Is it possible to add a bit of solder to the crimp connection to help with securing the wire or is this bad practice?

This is not such a good idea, for several reasons.

First, it makes the wire brittle. Second it does take extra time to do this to each terminal. Third, if you are not careful, it will leave excess solder that makes it difficult to insert the pin properly.

As I stated above, this seems to come down to how important is the joint, how important is the project? I have added solder to the joints for some of my projects, mostly because the crimper I have is poor and I do not want the crimps to come apart, but a well done crimp would be best.

In my experience the universal tool by molex WM9999-ND is a great tool for prototyping with a broad range of crimp pins, It does take more care,extra time and extra crimp pins as it usually takes a couple practice crimps to find the right crimp and care to make sure you align things perfectally and provide the correct crimp pressure. If you are doing more than prototype work or something that will be sent out to a customer it's best to have the tool designed for the contact. It will save you on the long run as you know the crimps will all be the same and the quality should be to MFG specifications.

We had one of the molex crimp tools in the lab at my last job and it worked well. I went to check the price because I know sometimes the connector crimpers can get ridiculously expensive but I just check the price and it was only $34 that is not bad.

"Molex Crimper WM9999-ND(crimper)":http://parts.digikey.com/1/parts/392052-tool-crimp-14-24awg-universal-63811-1000.html

This is what I do for one-offs. I don't agree with the issues cited against this, at least when you're making one-off cables personally.

About the wire being brittle: Only if you use too much solder. I'm thinking of the kind of crimp pins, like Molex KK series, that also have a section that grips the insulated wire for a short distance. As long as the solder doesn't flow past that immobile section, there is no harm done. Even then, if the wire is a little stiffer just past the pin, that's hardly much of a issue. Most connector hoods the pin goes into will have a little strain relief area too. In any case, I've never seen a failure due to this, but have definitely seen wires pulling out.

Yes, it takes a little extra time, but way less than dealing with even a single pulled out wire some time later, probably right before the customer demo.

You do have to be careful that the solder doesn't flow over the rest of the pin such that it won't mate right with the connector. Again, use just enough solder to fix the wire and pin together. I usually heat the pin and wire at the end of the wire in the pin, then apply the little bit of solder just to the wire end of the pin from the soldering iron. This keeps the solder flowing into the wire and between the pin and wire, and out of the way of the pin mechanics for mating with the header.

I actually go further most of the time and put hot glue around the wires coming out of the finished connector. I taper the hot glue over maybe 1/2 inch or so. This not only provides a strain relief for the wires, but also a place to grip the whole thing without putting stress on the wire/pin connections.

Again, this is for personal one-off use. For production use, get a real production house or cable manufacturer to do it.

I can see that if you spend time to solder the pin carefully as discussed above then you have no issues with stiffness or anything. I think you would also be spending a fair bit of time per pin to do this, which is just fine for prototypes.

I like all of the comments on this subject. That was the original idea anyway, see what others think and do. I actually purchased the generic Molex tool mentioned above by Cody, but I also purchased one of the fancier tools for the most common pins I will be doing. I want to compare the two myself and see if I feel that the time savings, and the quality warrant the cost.

Time savings, quality improvements and efficiency have value, For me the value is higher since I am motivated to spend less time on the production issue and more on the design. At some point the volumes would undoubtedly exceed my tolerance and using an external manufacturer would be the best solution, but an intermediate capability with "production quality" is desired.

Well I guess i'm a little late to the party, but at my job we are in the business of designing and then outsourcing the manufacture of harnesses.

I guess I missed which Molex contacts are in question, but I can tell you that on my desk right now are 3 different crimp tools, because the applications of each are very different and in the quantity of build that we are doing the "samples" I publish to our contract manufacturer must be correct, If I used a generic crimper to "make it work" that would open the door for them to follow the same poor crimps and anything that may not have passed their inspection now they have evidence to allow such manufacturing processes.

I think you were on the right direction with a consolodation of contacts used (pins implies male ) I would think selecting one contact family and buying the correct crimper/insertion/extraction tools to serve one family of contacts would be the most cost effective and buy the greatest peace of mind. You know you have the correct tools to do the job right, you will have to worry less about find/using the right tool for the job or keeping stock on several crimp tools.

I when first introduced to the cost of crimp tools was taken completely by surprise, only after more researching did i realize some of the contacts we were/are using cost over 2.00 per piece.

Also, I've been stuck on airplanes without the correct crimp tool, or soldering iron and it can be done with needle nose pliers and some patience for almost all variants of contacts, though certainly not advised.

I received one of the C-Grid/SL crimp tools today. This one is a 63811-8800. It is for 24-30 AWG wires. I did my first crimp and examined it under the microscope. I was impressed. It isn't a "little bit better". It is amazingly better. I really wish I had a CMOS camera for my microscope (one day). I would post some images of the old versus new.

Everyone has to determine where best to spend their development funds. I think I'm convinced that this is a worthwhile place to spend some of them.

One final thought - if you have EE friends in the area, sharing would be a nice option.