Affordable Molex KK Crimper? - Page 1
Forum section: electronics / general

author: angust_uk
author_rank: Regular Contributor
timestamp: November 27, 2024, 06:25:15 pm
content: I'm using Molex KK connectors and am getting tired of using pliers on the crimps! Does anyone have any suggestions for an affordable (i.e.non-Molex) crimper specifically for KK crimps?For the record, I did buy a generic one from eBay which claimed to support them, but it does a pretty terrible job as its jaws aren't the right shape.

author: mikerj
author_rank: Super Contributor
timestamp: November 27, 2024, 07:06:38 pm
content: You can do a lot worse than the Japanese "Engineer" crimp pliers (PA-20 is good for the KK crimps). They aren't ratchet crimp tools but they are nicely made, affordable and for small connectors like the KK I find them much easier to use than big heavy ratchet crimp tools.

author: angust_uk
author_rank: Regular Contributor
timestamp: November 27, 2024, 09:03:38 pm
content: Many thanks! I'll give that one a try

author: tooki
author_rank: Super Contributor
timestamp: November 27, 2024, 09:20:56 pm
content: Quote from: angust_uk on November 27, 2024, 06:25:15 pmAssuming you are talking about the 0.1" (KK 254) version: I find KK to be one of the more forgiving crimp contacts. I use my TE AMPMODU MOD IV crimper with them, which produces spectacular results, but I also get decent results with a cheap IWISS IWS-3220. They should work with many of the cheap D-sub crimpers, too.Reichelt sells an inexpensive crimp tool for their KK clone contacts:https://www.reichelt.com/ch/en/shop/product/crimping_pliers_for_psk_contacts-6844I've used that tool and it's actually not too bad.What I do not recommend is Molex's own $150 "ServiceGrade" crimp tool 0640160201. The dies on that were worse than on the $20 tool from Reichelt, categorically incapable of producing a good crimp, never mind an excellent one.Molex's more expensive tools (PremiumGrade) are fantastic, and perhaps worth buying used from an auction or classifieds site. (I've gotten several Molex crimp tools, brand new, for around $100 instead of $400+.) These produce flawless crimps.There is also a $60 non-ratcheting tool from Molex, 0638111000, but I've never used it. It's unlikely to be any better than the Engineer tool mikerj recommended.If you are talking about the large 0.156" KK version (KK 396), it is much less forgiving, as it has angled insulation wings, and requires a tool with a circular insulation die.

author: mtwieg
author_rank: Frequent Contributor
timestamp: November 29, 2024, 03:41:11 pm
content: Quote from: tooki on November 27, 2024, 09:20:56 pmMy work has a similar tool for 0.156" K terminals, the 64016-0205. It's hot garbage. Every Molex tool which uses a magnetic "terminal holder" is just... what the hell were they thinking? But this one in particular isn't just difficult to use correctly, I think it simply isn't designed properly for some of the terminals we use (which are listed in the application tooling spec).

author: Kean
author_rank: Unknown
timestamp: November 30, 2024, 10:39:29 am
content: Quote from: tooki on November 27, 2024, 09:20:56 pmI've got a couple of these non-ratcheting KK tools which I bought quite cheaply (either on discount or possibly part of a trial kit), and they are acceptable for the occasional use. No way would I buy them at the standard list price. They are no match for the non-Molex alternatives from suppliers like Engineer or IWISS (ratcheting), which generally have better dies and are available at a much lower price.Personally I hate the KK connector series. I used it a lot when I was less experienced, but won't use it in any new designs. I mostly use Molex Picoblade and various JST series (PH/SM/KR/SH/XH/EH/VH) depending on size/voltage/current requirements. I've invested many thousands of dollars in genuine crimping tools for most of those.

author: tooki
author_rank: Super Contributor
timestamp: November 30, 2024, 11:28:26 am
content: Quote from: Kean on November 30, 2024, 10:39:29 amWhat are the reasons you hate them?

author: Kean
author_rank: Unknown
timestamp: November 30, 2024, 12:23:32 pm
content: Quote from: tooki on November 30, 2024, 11:28:26 amLong term reliability due to oxidization and bad contact, often fixed by unplugging and re-plugging. Admittedly the parts used back then may not have been genuine Molex, sourced from local Australian suppliers where they were popular at the time (& still are). I found the spring shape of the contact just wasn't great, and the smaller contacts of other designs generally keep their shape and springiness better.I also dislike them because of their size and extra time needed for assembly of through hole parts. I moved to JST XH & EH series, which could still work in protoboard, but then moved to SMT as much as possible. I haven't looked in a while, but I don't recall SMT KK connectors. Pre-made cables are also readily available for other connector series, but I don't recall seeing them for KK. I recall making a lot of KK based ribbon cables in years gone by, but those products probably should have been designed to use IDC connectors.There are certainly more expensive contact plating options for KK, so if I am repairing something important that uses them I will now replace the contacts with gold plated ones. I still have plenty of old stock of the connector housings and crimps, mostly KK 254 but some KK 396.