Pcb fasteners / surface mount nuts / pems - Page 1
Forum section: electronics / general

author: loki42
author_rank: Frequent Contributor
timestamp: February 06, 2025, 12:43:21 pm
content: I'm currently using nuts for one pcb attachment and they are annoying / slow for my team.Has any one tried the surface mount nuts from Penn? How about using pems? I've got a pemserter but would prefer if they could be placed by the pnp. How about other press fits? I'm looking for m2.5

author: Kean
author_rank: Unknown
timestamp: February 06, 2025, 01:01:54 pm
content: I've done a few sheet metal designs using PEM style self-clinching nuts - typically M3 & M4 for mounting terminal blocks and earthing. Generally production is done in China, but I have a pneumatic press I use for small jobs as the local laser cutting place doesn't do it. I'd love a pemserter, but I don't do enough to justify one - so I just made up some simple jigs/dies.I think @seon (Unexpected Maker) was testing out some SMT nuts on a PCB design or two. Not sure if they are being placed on the Juki. I recall sampling some from Wurth a while back which came in T&R, but they didn't suit the design.

author: SMTech
author_rank: Frequent Contributor
timestamp: February 06, 2025, 01:45:57 pm
content: Various clients of ours seem quite fond of Wurth SMT threaded spacers.A recent prototype run used SMT M3 threaded studs for the power (I think the board required no THT/soldering on the rear side)Depending what you are fitting, we've also started using Wurth pushfit plastic spacers like thesehttps://www.we-online.com/en/components/products/SNFR_SNAP-IN_SPACER_REVERSE_MOUNTa much cheaper and quicker solution than a bolt, spacer and nuts. There's a quite a range of options to sift through depending on your use case. I like these toohttps://www.we-online.com/en/components/products/em/assembly/smd_spacer/smt_spacer_fast_tool_free_mounting.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 06, 2025, 02:07:02 pm
content: LCSC/JLC also have a range - search SMTSOFor more exotic variants & a wider range of sizes, Mac8 also do a lot of thesehttps://www.mac8japan.com/category/80

author: Ice-Tea
author_rank: Super Contributor
timestamp: February 06, 2025, 02:08:05 pm
content: Used MAC8 in the past. Did the job.

author: mon2
author_rank: Frequent Contributor
timestamp: February 06, 2025, 03:41:31 pm
content: We have used this company with success:https://we.tl/t-TWFiczN0AE?utm_campaign=TRN_TDL_05&utm_source=sendgrid&utm_medium=email&trk=TRN_TDL_05Quote

author: ftg
author_rank: Frequent Contributor
timestamp: February 06, 2025, 03:53:49 pm
content: I have used WE WA-SMSI in M3 with success.Replaced some screw towers with them.There seems to be an M2.5 version of WA-SMSI, so that could work.https://www.we-online.com/en/components/products/SMSI_SMT_STEEL_SPACER_M2_5_THREAD_INTERNALMaybe order a handful of samples and see if they work for you?

author: SMTech
author_rank: Frequent Contributor
timestamp: February 06, 2025, 03:56:00 pm
content: All these SMT spacer/nuts are basically the same product and they definitely work. Which to choose depends on volume, your best local supplier & availability; IIRC Mac8 was a pain to source, but it may have been peak Covid. You can get absolutely hosed buying Wurth through distribution vs direct.I feel a little resentment at the sheer volume of wasted plastic packaging involved in a tape of these items tho'

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 06, 2025, 04:42:53 pm
content: Quote from: SMTech on February 06, 2025, 03:56:00 pmMAC8 can be hard to get - in the UK,https://www.dmtl.co.uk/is their distributor, who are very helpful. RS also stock a few parts

author: Mangozac
author_rank: Frequent Contributor
timestamp: February 06, 2025, 09:56:05 pm
content: Quote from: SMTech on February 06, 2025, 03:56:00 pmThis. The price you get buying from Wurth is a fraction of what Digikey/Mouser charge. You don't even need to order full reels, but you do pay for freight so you have to balance that out.We've found the Wurth ones to be getting quite popular too.

author: loki42
author_rank: Frequent Contributor
timestamp: February 07, 2025, 02:23:01 pm
content: Local Würth got stuff or do you order from Singapore / elsewhere?

author: Kean
author_rank: Unknown
timestamp: February 08, 2025, 05:01:21 pm
content: Quote from: loki42 on February 07, 2025, 02:23:01 pmThe Wurth office in Melbourne (AU) have been very helpful in organising samples and production quantities.There are MOQs and you pay for shipping, but the overall savings vs other distribution more than make up for that.

author: Mangozac
author_rank: Frequent Contributor
timestamp: February 10, 2025, 12:46:08 am
content: Quote from: loki42 on February 07, 2025, 02:23:01 pmDealing with the local Wurth office but all stock ships from their overseas distribution centres.I haven't seen MOQs enforced but the cost structuring makes low quantities less feasible (even more so when the freight cost is added).

author: loki42
author_rank: Frequent Contributor
timestamp: March 19, 2025, 10:13:48 pm
content: Got an account with Würth. Quite surprised it's more than 10 times cheaper direct for a reel! Designed a few boards with them I'll see how they go.

author: tszaboo
author_rank: Super Contributor
timestamp: March 19, 2025, 10:27:56 pm
content: Quote from: loki42 on March 19, 2025, 10:13:48 pmThey are quite OK to work with. I select for example all the SMD caps from them, because they keep their 1210 or 0805 in production for years, and don't tell you to order their new 0201 caps.