Stackable 2.54mm headers that don't suck - Page 1
Forum section: electronics / projects

author: danie1
author_rank: Contributor
timestamp: June 12, 2020, 09:52:35 pm
content: I bought thesehttps://cpc.farnell.com/pro-signal/18688/header-female-stackable-2-54mm/dp/CN18764assuming they'd be functional since they are from farnell and not super cheap but I don't think they are fit for purpose at all.The pins are so thin they don't mate with themselves, dupont style cables or any other 2.54mm sockets I've got here. Normal 2.54mm pins are square pins but these are about half, maybe less, in one dimension so they don't make ANY contact at all with most sockets... they are literally balanced in there, no electrical contact.Mating them to themselves is loose unless you jam the pins past the teeth of the socket and into the plastic where they are pressed laterally against the other contact, not gripped by it's u shaped teeth at all.I wanted to have a moan about that, how can something be so crap and get to market? But more productively, does anyone know of a good source for stackable 2.54mm headers that make good contact and aren't silly prices? The turned pin sockets look nice but $3+ per unit is a bit rich for my blood.Thanks!

author: Benta
author_rank: Super Contributor
timestamp: June 12, 2020, 10:29:14 pm
content: Quote from: danie1 on June 12, 2020, 09:52:35 pmCheapness is cheapness. The ones you want are here:www.precidip.com

author: olkipukki
author_rank: Frequent Contributor
timestamp: June 12, 2020, 10:39:46 pm
content: Quote from: danie1 on June 12, 2020, 09:52:35 pmHave a look Samtec or Harwin, should able find one.

author: analogueAdder
author_rank: Contributor
timestamp: June 13, 2020, 02:45:52 am
content: Quote from: danie1 on June 12, 2020, 09:52:35 pmCrap connectors are becoming commonplace... China doesn't care. I have a breadboard that has a contact resistance of a few ohms.Quote from: Benta on June 12, 2020, 10:29:14 pmIndeed. And this is only going to get worse.

author: wraper
author_rank: Unknown
timestamp: June 13, 2020, 03:12:16 am
content: Quote from: Benta on June 12, 2020, 10:29:14 pmDunno about your link, I only see some trash with barely any gold on the contacts. No even an option for a decent gold layer.

author: jfiresto
author_rank: Frequent Contributor
timestamp: June 13, 2020, 05:53:46 am
content: I have been happy withthesefrom MPE Garry. If you need small quantities,Reicheltsells a selection for 0.04 ~ 0.09 euros per position, depending on the number of positions. They break away, especially the single row parts.

author: jpanhalt
author_rank: Super Contributor
timestamp: June 13, 2020, 06:12:17 am
content: Your male header can have square or round pins. You need to match the female header to whichever style you have.For round pins, Millmax machined sockets is what I use. I believe precidip (as mentioned) is similar.For square pins, Millmax also makes receptacles. They are rugged. Generally, I end up using Samtec, AMP or Berg-type. I stay away from the simple fork type receptacle you show. One criterion to consider is "mating cycles". That can be anywhere from just a few to hundreds. (FYI, USB mating cycles are in the 1000's.) I look for some sort of design with multiple contact points and springiness. The original Berg is one example, but is getting harder to find. Samtec's Tiger Eye is another. AMP also makes a nice series.

author: danie1
author_rank: Contributor
timestamp: June 13, 2020, 11:13:12 am
content: Thanks for the suggestions, I'll take a look at them all and maybe buy a selection.

author: Lomax
author_rank: Frequent Contributor
timestamp: June 13, 2020, 12:17:06 pm
content: I madesimilar observationsa while back, and eventually foundToby Electronicswho sell Samtec and Valcon 2.54mmheadersandsockets.

author: danie1
author_rank: Contributor
timestamp: June 13, 2020, 01:07:45 pm
content: Quote from: Lomax on June 13, 2020, 12:17:06 pmIn your thread you said you ordered a selection from them, were there any favorites/duds? It looks like the tiger-buy contacts from samtec are basically the same as the ones I have except square tails, correctly formed and probably not made out of cheese. The tiger-claw looked good too but I'd have to alter the PCBs for that (which I already ordered assuming finding decent headers would be no big deal!).

author: jpanhalt
author_rank: Super Contributor
timestamp: June 13, 2020, 02:26:50 pm
content: I mentioned the Berg connector. Here is a glossy description:https://www.connectortips.com/breakthrough-contact-design-spawned-500m-connector-company/It is made in both a crimpable version for wire to wire or wire to board and a pre-loaded version for board to board. It is very dependable and is the standard for many (most) model servo connectors. There are lots of imitations. Model applications are generally limited to 3 contacts. I routinely use 6-contact wire to wire connectors with Berg contacts.Digikey carries it, but it seems Mouser has a better stock. Unfortunately, the original Berg company underwent some acquisitions (I would sell out my namesake company for $500 million too). It is currently owned by FCI/Amphenol. Unfortunately as miniaturization keeps getting smaller, the original Berg is too big. Amphenol has connectors with various plays on the name Berg and the datasheets refer to a spring, so I suspect they are similar, but perhaps not identical.To me, the essential part is the spring contact. Other versions I mentioned also have springiness.Although it is getting harder to find, if you are interested in 2.54 mm, it is where I would go. For 2 mm, as mentioned, I go to Samtec.

author: danie1
author_rank: Contributor
timestamp: June 13, 2020, 05:52:15 pm
content: That Berg glossy is pretty cool, looks like that would give great contact.I could actually convert to 2.0mm in the next version to use the Samtec tiger eye contacts; I went for 2.54 purely because I assumed it would be easy to find stackable headers thanks to arduino et al, a slightly more compressed connector would make the layout easier actually as long as I can still squeeze a trace between the pins.

author: Buriedcode
author_rank: Super Contributor
timestamp: June 13, 2020, 09:25:42 pm
content: Quote from: Lomax on June 13, 2020, 12:17:06 pmI'll second Toby. Only used their Samtec connectors but never had issues with them, and the connectors were always top notch. Their selection is pretty impressive, especially for lower profile "standard" connectors. They also allow for small quantity, which is great when prototyping.

author: westfw
author_rank: Super Contributor
timestamp: June 15, 2020, 06:25:32 am
content: Samtec SSQ series, with the -3 (stacking) or -4 (tall stacking) "lead style"https://www.samtec.com/products/ssqDon'tget the SSW option; those leads are much too WIDE to fit in a socket for 0.025in posts.

author: Lomax
author_rank: Frequent Contributor
timestamp: June 15, 2020, 09:33:40 am
content: Quote from: danie1 on June 13, 2020, 01:07:45 pmNope, all good.Thesewere the female stacking headers I bought, in 2x20 and 2x13. I also boughtmale stacking headers, someextra tall male headers(which have proved very handy), and a few other bits & bobs. Toby have a great catalogue of rare and useful board-to-board hardware, including a huge variety ofPCB spacers, which I use a ton of. For some reason these tend to be ridiculously expensive elsewhere.

author: tooki
author_rank: Super Contributor
timestamp: June 15, 2020, 12:31:51 pm
content: Quote from: wraper on June 13, 2020, 03:12:16 amThickness of gold layer isn’t the only criterion. Most definitely Preci-Dip is not “trash”. For a lot of applications, a quality tin-plated contact is going to be more reliable than a junky gold-plated one.

author: wizard69
author_rank: Super Contributor
timestamp: June 15, 2020, 07:30:49 pm
content: Quote from: analogueAdder on June 13, 2020, 02:45:52 amThis is so true. Unless your really know your way around the supply chain in China, you are better off avoiding brands from China. Being manufactured in China isn't as big of a problem, the problem is the ripoff and copy culture in China where far too many "businessman" try to make a buck by ripping off somebody else's design. Businessman in quotes because there are plenty of honest businesses in China but they have plenty of unethical businesses to contend with.QuoteWell no we can refuse to pay for crap or even buy it in the beginning.There are lots of discussion in these forums with respect to bench power supplies. Some of the commercial ones from China are just terrible and do things like screw up terminal spacing (which is an example of not giving a crap). However try to convince somebody to spend a few bucks more for a decently constructed supply. This especially when you try to relate the cost per day over the life of the instrument.