Pin Connectors, Crimpers, decent connections, and the futility of it all... - Page 1
Forum section: electronics / projects

author: Dundarave
author_rank: Regular Contributor
timestamp: February 07, 2019, 04:48:18 am
content: I've been trying to make reliable connectors using the pins/connector/crimper system shown in the photo, but no matter how much I practice, I can never crimp on a pin, male or female, that will slide nicely into the connector while forming a solid mechanical and electrical connection with the wire. The top of the crimp invariably ends up too wide to fit properly, despite trying to pre-form the pin's metal "wings", and not squeezing to the extreme end of the tool's travel.So I thought I'd ask if anyone has been able to be consistently successful at doing this, or if it's a well-known hopeless cause and I'm just late to the party. I used to be pretty good with spade lugs back in the day, so I'm generally used to crimpers and the need to finesse them, etc., but I'm ready to abandon this and see if soldering the wire to the pin is a better approach. I've just wasted hours debugging a project module that was ultimately caused by flaky connections to my RPi header.I thought perhaps the crimpers themselves were the problem, as the inexpensive ones I'm using make it near impossible to reliably judge the depth of the stripped wire (and are ultimately responsible for the deformed result in any case). If manually creating decent pin connections is actually possible, does anyone have a recommendation for the brand of crimpers that will make them so?Thanks -

author: RobertHolcombe
author_rank: Frequent Contributor
timestamp: February 07, 2019, 05:07:37 am
content: Its hard to tell from the photo, but I've experienced the same issues, I just overcome it with a pair of needle nose pliers after crimpingI'd guess this is just due to low cost crimpers not being manufactured to the right spec

author: helius
author_rank: Super Contributor
timestamp: February 07, 2019, 05:16:53 am
content: http://www.engineer.jp/en/products/pa09e.html

author: Dundarave
author_rank: Regular Contributor
timestamp: February 07, 2019, 05:38:54 am
content: Quote from: helius on February 07, 2019, 05:16:53 amThanks, Helius, for that link to the Engineering Inc. crimper! A quick Google query turned up a practical review of the tool, by a tech who was experiencing the same frustrations with the cheaper crimping tools. The video demonstrates an excellent comparison between the Engineering Inc. crimper and a cheap $12 crimper pretty much identical to the one I'm using. The tool that Helius recommended is C$60 on Amazon, however, but looks like it's worth it. (to me, anyway. Any excuse for a new tool...) I'll be ordering it shortly...

author: Psi
author_rank: Super Contributor
timestamp: February 07, 2019, 05:41:39 am
content: Most manufactures of little crimp connector pins do not conform to any standard. They invent their own system and sell their own crimp tool for $300-20000, i'm not kidding.They have to make their own tool anyway, since anyone wanting to crimp their connectors correctly and to spec will want an official tool guaranteed to work. So they have a reason to use a custom format and make you buy the tool from them at a high price.ExampleHere's the official TE Connectivity crimp tool for their AMP series VAL-U-LOK pins (the type of pin used in 24pin computer ATX powersupply plugs)You'd think this tool would be cheap, since all computers use a version of it. Nope US$370,https://www.digikey.com/product-detail/en/te-connectivity-amp-connectors/91388-1/A30667-ND/701672There's a reason why the "Crimpers, Applicators, Presses" section on digikey has 15958 different crimp tools.Page 1 starts with big crimp machines worth $400,000 and even after page 28 your still looking at hand crimpers worth over $1200Lots of china crimp tool copies exist, you just need to find the right crimp tool for the connector pin you have. I've found there is a wide range in quality when it comes to 3rd party crimp tools. Some work fine, ya just need to find a good one.And please, no one bring up the idea of crimp+solder, this thread will get to 400 pages of arguments.

author: jfiresto
author_rank: Frequent Contributor
timestamp: February 07, 2019, 12:17:59 pm
content: The wire size, die and contact must all be compatible to get reliable crimps. That is not always easy. I had to buy the tool thatPsilinked to, to reliably crimp some PE Series 4.2mm (Mini Fit Jr.) contacts. It only cost half as much back then. I tried three different dies in one of the best crimping frames made, only to discover none was compatible.The contacts you are crimping look a bit different. Do you know the manufacturer and series?

author: FrankE
author_rank: Regular Contributor
timestamp: February 07, 2019, 12:53:43 pm
content: Are those the so-called Dupont connectors used for headers on motherboards, Arduinos and ESPs?Yeah couldn't make a tidy termination with those cheapo crimpers either.I think I developed dyslexia looking for matching 'pro' crimpers and terminals on RS, Farnell and Digi-Key.

author: Siwastaja
author_rank: Super Contributor
timestamp: February 07, 2019, 01:10:54 pm
content: You found out what results in from the common misconception of just buying a "crimping tool".Crimping never works properly this way. It's a complete, integrated system, where all parts must be the exact same series from the exact same manufacturer.The only way it works acceptably seems to be:1) You work in a large company,2) Your boss can hire someone just to decipher the catalogues of the connector industry giants, and communicate with the representatives of said parties, and therefore:3) after years of work, you end up obtaining the matching product line of contacts and automated crimping machines. The manual crimp tool typically costs around $500 but is only relevant in the R&D lab.Done right, this is both reliable and cost-effective (when you need millions of crimps). For hobbyists and small companies, it's a complete hit-or-miss, with a massive "luck" element.Sometimes, pre-crimped leads are available from the connector manufacturer.Often, Aliexpress/Ebay Chinese pre-crimped leads are just fine, often better than trying to crimp with the wrong tools.Finally, don't underestimate the option of just soldering for one-offs/small batches.

author: IDEngineer
author_rank: Super Contributor
timestamp: February 07, 2019, 02:25:03 pm
content: Connectors are literally my least favorite part of this industry. Truly the definiton of "necessary evil", and I suspect where we first got the phrase "The nice thing about standards is there are so many different ones to choose from". Connector bodies, their contacts, and the labor associated with them are often the most expensive part of a system and also the least reliable.I have boxes and bags full of dissimilar connectors. Everyone wants something different. I recommend a 25 cent connector body to a client and they come back insisting that we use a $5-6 body with full IP67 rating despite that it will never ever be exposed to anything but a dry, quiet, peaceful environment.Grrrr.

author: max_torque
author_rank: Super Contributor
timestamp: February 07, 2019, 08:10:59 pm
content: The best thing about most connector systems is that the manufacturers and specifically the distributors deliberately (as far as i can tell) completely fail to even start to cross link or reference all of the actual parts you need to complete a fully assembled pair of connectors!Buy the housings, then spend 3 days looking for the matching contacts, and anther week trying to find the little contact locking plastic plate, and 3 months later you may even strike it lucky and on the 14th order attempt even get a backshell that actually fits......

author: timelessbeing
author_rank: Frequent Contributor
timestamp: February 07, 2019, 08:28:13 pm
content: I use tool-less connectors whenever possible for this reason.

author: stj
author_rank: Super Contributor
timestamp: February 07, 2019, 08:43:55 pm
content: so are there any official outlets/sellers for "Engineer" tools in Europe / U.K. ??i wouldnt mind a Pad-02 set, but at those type of prices i'm sure there are clones around.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 07, 2019, 08:50:34 pm
content: And then there's IDC connectors. Stupid easy to make up, can even get passable results with a flat blade screwdriver. Good results, though -- reliable? Not even the wiring houses can manage.Related subject, I had another example of this, the connectoconfusopoly. Had spec'd a 3M 30310 series header. I know they make these with holes in the ends, so you can fit a retention clip over the plug; nice, right? I thumb* through the 3M catalog looking for these mates, since I'm responsible and I want to get it from the horse's mouth, not just assuming that what looks right will work. A dozen minutes later and I'm looking at the only clip they offer, and it's for the 2500 series headers.Naturally, they don't provide dimensions on where those clips hook onto, so it's anyone's guess if the clips work or not. Long story short, I have to offer the customer the retention clip option with a BOM substitution to be sure it works (or to pick up some clips and, you know... try them? ewww).*Virtually of course.Even more tangential, press-fit connectors -- heard one engineer was invited to a presentation by an FAE selling these sorts of connectors. Later into the presentation, he proclaims their process has a "99.7% connectivity rate!" Our engineer raises his hand with a grin, asking: "Great, so if I have a thousand-pin connector on my backplane, can you tell mewhich threepins have failed?" The meeting ended soon after...Tim

author: stj
author_rank: Super Contributor
timestamp: February 07, 2019, 11:06:18 pm
content: if by IDC you mean the punchdown type, those are easy.but i hate them, there is no cord-grip/ clamping - they turn into wire strippers if you pull too hard!

author: Psi
author_rank: Super Contributor
timestamp: February 08, 2019, 12:12:53 am
content: One thing you can do to find a cheap china crimp tool for a connector is to message and ask a connector business on aliexpress/alibaba.For any semi-common connector pin they will know what crimp too to use, or will know someone else nearby who they can ask. (Most of the time its just a little Shenzhen store, so it's very easy/quick for them to walk 50meters to the crimp tool store and ask/buy one)Most china crimp tools are like ~$20 so if you say you will be ~$50 they will be happy to figure it out for you and take the $30Obviously it depends who you ask, dont just ask a random seller. Look for a business on aliexpress that deals a lot in connectors. but most of the time this approach works to get you a crimp tool that works and doesn't cost $800.Even if it takes you a few attempts to get a good tool it's still way cheaper than $800 for an official tool.

author: HwAoRrDk
author_rank: Super Contributor
timestamp: February 08, 2019, 09:36:43 am
content: Quote from: stj on February 07, 2019, 08:43:55 pmI have no idea as to how official they are as a reseller, but I bought my Engineer crimpers from a UK eBay seller named 'precisehandtools'. They seem to sell and stock a lot of them.

author: mac.6
author_rank: Regular Contributor
timestamp: February 08, 2019, 10:02:49 am
content: Quote from: stj on February 07, 2019, 08:43:55 pmdo you mean PA-20? I got mine from amazon-FR (still listed at 36€). No clones but don't care as they are really fine crimpers, way above anything from china I got.

author: mariush
author_rank: Super Contributor
timestamp: February 08, 2019, 12:54:25 pm
content: Yeah, I also bought the PA-20 from Precise Hand Tools on ebay (remove spaces).At some points, they also sold on Amazon UK if I remember correctly.TME.eu (Europe, Polish company) seems to be stocking them and the prices look good to me :https://www.tme.eu/en/katalog/#search=engineer&s_field=accuracy&s_order=DESC&id_category=100115&page=1Their shipping is typically decent, a few euro per package or something like that. Order it with solder flux or solder wire and shipping costs will matter less.

author: stj
author_rank: Super Contributor
timestamp: February 08, 2019, 03:32:44 pm
content: Quote from: mac.6 on February 08, 2019, 10:02:49 amno, the universal set.http://www.engineer.jp/en/products/pad11_13e.htmlbecause i only want to spend the money once!

author: Dundarave
author_rank: Regular Contributor
timestamp: February 10, 2019, 01:24:24 am
content: Just to follow up: I received my PA-09 crimpers from Amazon.ca today for CAN$61.00. It contains dies for 1.0, 1.4, 1.6 and 1.9mm Dupont connectors (and other systems, I'm sure). A bit expensive, but I can attest that they work perfectly as advertised and reviewed by others.In my opinion, if you really want to crimp your own Dupont connectors, there's little point in trying to make do with $20 - $30 Chinese crimpers: you're just wasting your time and frustration tolerance. As far as I'm concerned, the base cost of entry for crimping usable Dupont connectors is the PA-09 crimper plus the connectors themselves.Thanks to Helius for the initial pointer to the PA-09.

author: LukeW
author_rank: Frequent Contributor
timestamp: February 10, 2019, 10:13:00 pm
content: From the OP photo, it looks like you’re dealing with those no-name 0.1” “DuPont” generic connectors, in a small-scale lab or hobbyist application. (If not, what is your context/requirements?)In general, without thousands of dollars for the proper tooling, manual work with needle nose pliers and sometimes a tiny touch of solder is good enough for this context, and broadly applicable across multiple connnector families.Or buy the generic “DuPont” crimped jumper wires, either without housings or the individual pin housings, and repack them into housings of whatever number of pins you desire with the pinout you want. (Note that if you’re buying 2.54mm black “DuPont” from Samtec or some other name brand, the pins and housings are not interchangeable with “China Generic.)

author: Neomys Sapiens
author_rank: Super Contributor
timestamp: February 11, 2019, 09:32:22 pm
content: I have several crimpers for this kind of contacts (B-crimp). Those by Weifmueller, Knipex, Klauke etc, which look like the one you have, with somewhat better designed dies, are satisfactory at best. One from Packard Electronics and the 169347-1 from AMP are a bit better, my preference is the GMT-225 from Daniels.

author: xavier60
author_rank: Super Contributor
timestamp: March 23, 2019, 10:55:02 am
content: The PA-09 properly crimps the electrical connection on Dupont connectors but I couldn't get it to crimp the insulation wings properly causing the connectors to be difficult to insert into the housing.The triangle shaped wings need to be formed into a circle, not curled in. Unless I'm missing something, the PA-09 doesn't have a die for doing this.I made a 1.5mm circular die opening with my Dremel rotary tool.The wings need to be pressed parallel first with the plier end of the crimper.I'm able to make reliable crimps on AWG 28 IDC cable by folding the strand bundle.

author: Dundarave
author_rank: Regular Contributor
timestamp: March 24, 2019, 07:57:05 pm
content: I've had what I consider good success by using the PA-09's 1.6mm die for the "barrel" part of the connector, and the 1.9mm die for the "wings", both used with a carefully-moderated level of force.I thought it was possibly a better mechanical bond to have the wing tips actually fold into the insulation, as opposed to simply surround it, but perhaps its a question of taste. I've included a shot of what that looks like.

author: stj
author_rank: Super Contributor
timestamp: March 24, 2019, 11:22:07 pm
content: automated machines usually pierce the insulation with the folds, i assume that's intentional or they wouldnt do it so cleanly.

author: xavier60
author_rank: Super Contributor
timestamp: March 25, 2019, 02:49:03 am
content: Quote from: Dundarave on March 24, 2019, 07:57:05 pmWhat size wire are you using? I mainly use folded 28 AWG which is 25 AWG.I find that the 1.6mm die doesn't quite crimp tight enough and I need to use the 1.4mm die.Although the crimps always seem ok, I'm starting to dislike the high initial crimping force that I need to apply to start the wings curling.This force is attempting to shear off the wings.And the connector becomes stuck in the die.

author: tooki
author_rank: Super Contributor
timestamp: May 22, 2020, 11:01:54 am
content: Quote from: Dundarave on February 07, 2019, 04:48:18 amFYI, the issue is that 99.9% of the crimpers out there that are sold for “DuPont” terminals are actually the wrong tool. The crimper you have (I have the same one) are designed for 2.8mm spade connectors, which are designed to have an m-shaped (“type F”) insulation crimp. In such terminals, both the wire crimp and the insulation crimp parts of the contact have symmetrical, rectangular “wings”. DuPont terminals, on the other hand, have asymmetrical triangular insulation crimp wings. These are designed for a circular crimp that wraps the wings around the wire without piercing the insulation. In the wrong tool, the wings get mangled, causing the distortion that prevents their proper entry into the housing.A quick fix is to re-crimp the insulation crimp in the wire crimp jaw. On my crimpers, if I squeeze carefully until the very first click that releases the ratchet, it’ll fit the housing fine.As for finding the right tool: I’ve started documenting my saga to find a better tool. I recently found some promising candidates, one of which I ordered and am awaiting delivery on. Here’s the link:https://www.eevblog.com/forum/reviews/affordable-crimp-tools-for-small-connectors-(dupont-etc-)/