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When I design a printed circuit board, I often put 100mil male header anywhere. Sometimes I think it would be better to place some connectors for more reliability. Anyone here knows which connector/crimp/tool combination is good and cheap? I recall that some of the Molex crimp tools are 200-300$ range and more... a bit too pricey for me. So I'm looking for a connector series and the associated crimp tool.

Speccy
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  • You can get a manual crimp tool for somewhere in the neighborhood of $20. But once you've debugged 2 or 3 flaky contacts, you'll wish you had payed out the $100-150 for a better tool. – The Photon Jan 24 '13 at 17:13
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    Molex 64016-0200 tool for Mini-Fit Jr connectors (better for power than for signals) was only $120 when I last checked. – The Photon Jan 24 '13 at 17:14
  • @The Photon the Mini-Fit Jr connectors looks really great for what I need, thanks I'll take a look – Speccy Jan 24 '13 at 20:07

3 Answers3

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For one-off use like test points not used in the final version, the Molex KK series can be useful. These are cheap, widely available, and crimp tools are also available cheaply.

When making crimps with the hand tool, just assume it won't be the best. I always follow up by flowing a little solder into the connection. That has helped a lot in the past. Again, this is for personally made one-off crimps, not professionally made crimps with the best machines. Some even say soldering hurts a properly done crimp.

I have done hand-made crimps both with and without soldering, and the soldered ones are by far better. Without solder, the wire can work its way loose, make intermittent contact, and eventually even come out. Often a crimp that looks good isn't. Assume visual inspection without special tools is only for catching the gross obvious stuff, not details like how solidly a wire is really being held.

Olin Lathrop
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  • On Newark website I can find http://bit.ly/YqntvR - do you have any links for cheap crimpers, or do you suggest to close the crimp with a regular plier? – Speccy Jan 24 '13 at 20:05
  • I've got several crimpers around here and don't remember where they came from. I think at least one from Jameco. Be careful, some really are junk, but you should be able to find one that works well enough for a few 10s of $. The crimp doesn't have to be perfect if you follow up with a little solder. No, I don't suggest using plyers. – Olin Lathrop Jan 25 '13 at 11:58
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Look up Molex KK Connector kits on a site such as Mouser. (For example, 538-MXKK-100.) You may notice that some of the kits include a crimp tool. I discovered that these crimp tools are also available separately. While they are not the $300 optimal model, they do work well and are a tenth the price. The kit I linked, contains Molex Part No. 63811-1000 which is less than $40.

Personally, I bought a crimp tool (#1928) from Pololu.com for $35 and think it does a great job with Molex KK connectors. However, I also bought some of the crimp pins and housings from Pololu and do not recommend them. The Molex brand, while more expensive, is superior in quality.

Last but not least, I requested some samples of various 100 mil headers and housings direct from Molex and was pleasantly surprised when I received a small box of parts just two days later. Highly recommended if you need to test a few connector types before you make a big purchase.

Edit:

Not many places show the beginner how to actually crimp the pins for these type of connectors. There is, fortunately, a quick video that shows hand-crimping small KK pins.

JYelton
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  • Thanks for part numbers. For the price of 76650-0009 kit I suggest other vendors than Mouser... Mouser : 124.60$ ; Digikey : 71.92$ ; Newark : 53.63$ – Speccy Jan 25 '13 at 12:53
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I answered a similar question here: Assemble PIC connector from bits.

Basically I have tried both the dirt cheap Molex crimper, the intermediate $40 ones and the $200 version. You definitely get what you pay for: quality of crimps goes up with price.

Note that there are IDC versions of the Molex MTA100 (0.1" spacing) female connectors that are easy to use if you don't want to crimp. There is an IDC tool to push the wires into the slots that costs about $20, but I get away with a homemade version.

lyndon
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