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Comment by alright2565 | Hacker News Reader

I wouldn't recommend crimping your own hookup wires as a hobbiest, especially not dupont. The unofficial tools for dupont mostly all suck, and the official tools are $400+[1].

[1]: https://www.mattmillman.com/info/crimpconnectors/dupont-and-...

For my own crimping of dupont, I'm using the Iwiss SN-025 which works OK, but even then I've mostly switched to Mini-PV because I was tired of the dupont receptacles wearing out after 5 cycles.

The pictured SN-28B is definitely not good for dupont, which has a totally round cable holding ring. Amazon/Aliexpress sellers don't know anything about what they are selling.

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In the Voron 3D printer scene it has become quite popular to use the ENGINEER PA-2X series if you want to spend tens of £ rather than £3 (and don't have hundreds of £ for official tools).

Despite your link saying they "suck", I've found the light-touch, fully-manual nature of them give a much better feel for what you're doing (vs the cheap ratcheted ones; never used the official tool), and I got pretty efficient at crimping with them throughout my Voron 2.4 build.

The article said that Engineer PA-24 is good since it has cylindrical dies! I haven't tried it since I wanted to do the full crimp in one motion. Maybe that desire was irrational.

I'm not entirely sure which one I have, since I seem to have misplaced it, It's a PA-2X, where I'm not sure what the X is. By "cylindrical dies" is it referring to the shape of the inside of one-side of the die? What's the alternative?

I do recall that the design of the one I have, has little protrusions on one side of the die to encourage the wings to wrap under, so that they form a sort of m shape, with the ends of the wings "pressing" into the wire's sheathing for a nice grip. They cost somewhere in the region of £40-60 but I don't recall exactly.

I need to go and find out why they're not on their hanger on the pegboard I'm looking at, where they should be.

This is mini-pv, but dupont is the same concept: https://i.imgur.com/bV1zUkm.jpeg

It's designed for an oval crimp around the insulation & a m-crimp on the wire. The typical cheap crimpers have two sizes of m-crimp, which is fine for a lot of JST connectors for example, but not this.

Ah, thanks for the explanation, that makes perfect sense.

I've not seen an m-crimp on both sides yet, sounds like it wouldn't work very well at all unless you had two wings on the connector itself to m-crimp the ends of, which I've also never seen!

Hey, this is good info. I’ve got the pictured Amazon seller kit, and it works really bad!

For the task of connecting 2.54mm “pin headers” on boards you prefer mini-pv. A little hard to search for, but does this require a special crimper of its own?

As a hobbiest you don’t recommend doing your own crimping at all, and I am willing to pay money, but I do kinda need specific lengths due to a tight enclosure without much room for excess ribbon (I guess round cable might be bit better). Is there such an option? I kinda searched for it, and on electronics retailers like digikey I didn’t really see the length I wanted, though it is easy to miss stuff on there.

> A little hard to search for, but does this require a special crimper of its own?

The IWISS SN-025 works well for the Mini-PV too. Which makes sense, since the dupont connectors are a near-clone designed for cheaper production.

> As a hobbiest you don’t recommend doing your own crimping at all

I just don't find it very enjoyable, especially getting to the point where I have tools that are actually suitable! The IWISS SN025 is fairly new[1] and before I ran across Matt's blog, reliable information on this subject was hard to find.

But I mean I have after all gone through the effort of getting tools and connectors, so it's more of a medium "recommend against" rather than a "not worth doing at all". It's almost like my preference with assembling PCBs. I don't mind that as much, and am good at it, but if I can just pay someone $20 to do it for me, I'll do that instead. Except I don't think there's any services at that price point for cable harnesses.

[1]: https://www.mattmillman.com/iwiss-sn-025-another-head-scratc...

> Except I don't think there's any services at that price point for cable harnesses.

I don't know of any either, but you can design around ready-made cables. Mouser and Digi-Key carry a pretty big selection.

As a counterpoint to official tooling:

I used a Engineer PA 09 which, despite its cheap look, is f'n amazing!

I crimped all wiring on my Voron myself, took some time getting used to it - but was almmost Zen-like meditation afterwards :)

Not only are most third-party crimp tools kind of marginal, but if you're buying connector kits of Amazon/ebay/Aliexpress etc you're getting knockoffs too, so you have a lot of degrees of quality freedom between your crimp pin and your tooling.

And you're probably getting your connector and its mate from different manufacturers, too, which can have its own set of issues.

What is the real-world problem you’re concerned about?

Cheap tools may not crimp as well as the official tools (I have no doubt the differences in finished crimp geometry are real), but especially for low voltage connections like these, I have a hard time believing the end result is dangerous, or even particularly unreliable.

I don't have a problem with cheap tools. The problem is that lots of the crimpers sold for dupont just are not designed for them at all. It makes a big difference for both how long it takes (these tiny connectors move around a bunch) and just a minimum level of crimp quality.

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