Crimping quick disconnect connectors for small (24AWG) wires - Page 1
Forum section: electronics / general

author: dkonigs
author_rank: Regular Contributor
timestamp: March 14, 2025, 01:53:56 am
content: I'm working on a project where I want to attach 24AWG wires to a switch with big quick disconnect tabs. I'm currently just soldering them, but I'd rather avoid that if I can. The vast majority of quick disconnect connectors are designed for larger wires, so its hard to find good options.After some digging, however, I've found these two choices from Molex:19016-0099- Krimptite Quick Disconnect for 24-26 AWG19003-0068- InsulKrimp Quick Disconnect for 24-26 AWGThe problem with both of these connectors is that I cannot figure out what I'm actually supposed to crimp them with.Okay, Molex has their own crimping tools. But in typical fashion, they're obscenely expensive and each connector uses a different tool. So given that I'm not entirely sure which one I'd prefer, or how they'd work out, its a bit much for simply trying out my options.But while 3rd party crimping tools for these things are commonplace, I can't seem to find any that'll actually do connectors for wires this small.The closest I came is thisAven 10189tool I found on Amazon, but it didn't actually work very well. The wire didn't stay securely in the terminal after crimping.So any suggestions?

author: thm_w
author_rank: Super Contributor
timestamp: March 14, 2025, 09:14:10 pm
content: Existing thread here:https://www.eevblog.com/forum/projects/good-ratcheting-crimper-for-22awg-in-red-quick-connectringspade-terminals/Show some photos. For sure the wire is 24AWG right?You can try adjusting the Aven tool.

author: dkonigs
author_rank: Regular Contributor
timestamp: March 15, 2025, 02:54:28 am
content: Yeah, I've already looked through that thread. No, there's nothing to "adjust" on the Aven crimper. It simply doesn't hold the wires securely after I crimp them.And yes, I'm sure the wires are at least that small. They're pre-made jumper wires designed to go into a JST PH connector, specifically these:https://www.digikey.com/en/products/detail/jst-sales-america-inc/ASPHSPH24K102/9918854I'm basically trying to make a little wiring pigtail to connect this quick disconnect tab switch to a JST PH plug. Its possible that different connectors would crimp better with a generic tool, but its hard enough to find anything that admits to working with wires this small.

author: Smokey
author_rank: Super Contributor
timestamp: March 15, 2025, 02:59:20 am
content: Tiny gauge wire tends to break in those types of terminals.I'm not recommending you do this for anything important, but you can always double over the stripped section of wire and crimp it with the non-insulated section of the crimper. That usually makes about as good a crimp as you can get with tiny wire and those types of terminals. Heads up that without some strain relief, the wire will want to break at the terminal.

author: dkonigs
author_rank: Regular Contributor
timestamp: March 15, 2025, 03:41:29 am
content: Makes me wonder if I should just stick with soldering the wires, and try to be careful enough on temperature to avoid melting the switch. Its just one of those "fiddly" assembly steps I'd rather avoid. It might get easier if they made crimp inserts for JST PH connectors that could take thicker wires, but they really don't.And thus is the problem with wanting to use a rocker switch rated for mains AC and with a good "ker-thunk" for something that's just toggling a low voltage digital input on a microcontroller system.

author: wraper
author_rank: Unknown
timestamp: March 15, 2025, 03:46:24 am
content: if it's for low quantity, you can simply use connector for thicker wire, strip longer portion of wire and fold copper strands back and forth to reach required cross section.

author: tooki
author_rank: Super Contributor
timestamp: March 15, 2025, 11:50:08 am
content: Quote from: dkonigs on March 14, 2025, 01:53:56 amI just finished a project using a total of 50 insulated fork terminals crimped onto 24AWG wire. Indeed, I don’t have a tool for the extra-small yellow insulated crimps, either. So I did what wraper said and used the red terminals, and stripped off double the insulation length and folded it over. This works perfectly, since the cross-sectional area of two 24AWG is about the same as one 20AWG, the minimum for the standard small (red) insulated crimps.Another option, in theory, is to bulk up the wire with a sleeve. I have seen this option (with manufacturer endorsement) on some circular crimp contacts and some large power lugs. I’ve been reluctant to do it myself on terminals not designed for that, or more accurately, using sleeves not expressly designed for that. I don’t trust that regular wire-end ferrules (which are usually brass) could handle being crimped twice (if already crimped onto the wire). I think I’d be more comfortable if I found copper sleeves. I haven’t looked yet, to be honest.You can also bulk up by inserting short lengths of extra wires into the terminal at the same time. For example, adding an extra 1-3 24AWG wires, or a single 22 or 20AWG, in a red terminal will put you comfortably into the terminal’s wire range.You can get cheap AliExpress crimpers for the extra-small insulated crimps, models SN-02C (the C is critical!!) which use a yellow dot for the extra-small cavity, and the larger HS-40J that marks extra-small with green, since it also has the large yellow cavity. I’ve been meaning to order one to try out. But like with your Aven, the cheap Chinese tools for insulated crimps that I have tried so far (for regular red/blue/yellow sizes) have been disappointing, with terminals not securely crimped, particularly on the low side of the wire range for each cavity. (It also depends on the quality of the terminal: some cheap terminals are made of unusually thin sheet metal that ends up providing too little material in the crimp barrel. Those can fail even with good tools. This won’t be a problem with Molex, TE, etc.)As for the uninsulated terminal, I have had no trouble crimping small wire to such things, but the old crimp tool at work that I use for those is unmarked, so I have no idea who made it (or when), nor a model number.So if you have a tool that works reliably for larger-gauge wire, and you’re not doing a thousand pieces, I’d do the folding back. It’s easy and works.

author: tooki
author_rank: Super Contributor
timestamp: March 15, 2025, 11:53:50 am
content: Quote from: dkonigs on March 15, 2025, 03:41:29 amIn the same project, I solved a similar problem (connector with one maximum wire size, and a transformer with much thicker wire, with extra-thick insulation to boot) by simply crimping a length of thin wire onto the connector terminal and then joining those with WAGO 221 lever nuts. Not something you’d do in mass production, but perfectly legit in prototype/one-off types of projects.

author: tooki
author_rank: Super Contributor
timestamp: March 26, 2025, 12:00:41 am
content: Quote from: tooki on March 15, 2025, 11:50:08 amHuh, well it turns out I already own an SN-02C. I’m gonna take it to work and test it on some extra-small yellow terminals.

author: dkonigs
author_rank: Regular Contributor
timestamp: March 26, 2025, 03:07:17 am
content: I'm a little tempted to try one of the official crimpers, as crazy as it might be, but not both. So then the question is whether to do the insulated or non-insulated terminals. I suspect the non-insulated ones will get a better crimp.(I'm currently covering the solder joints I'm using right now with heat shrink, however, but I don't think that's actually necessary for anything beyond wanting it to look nicer in a place nobody will look.)

author: tooki
author_rank: Super Contributor
timestamp: March 26, 2025, 08:33:47 pm
content: Quote from: tooki on March 26, 2025, 12:00:41 amSo it definitely does not work with Molex 0190030068 fully-insulated terminals. They're apparently designed for a single crimp on the conductor, and no insulation crimp. The SN-02C crimps the insulation funnel, which just shears off the wire!I'm guessing it'll work on partly-insulated terminals like TE 165619-2 and 3M 70F-110-32-PB. I'll have to order some to try.