What tool do you use to tighten these weird nuts on some banana plugs? - Page 1
Forum section: electronics / beginners

author: mindcrime
author_rank: Unknown
timestamp: July 06, 2021, 10:16:18 am
content: Most panel mount banana plug connectors I've seen (and most of the ones I have) use a hex nut to tighten the thing to the panel, but recently I ordered some similar to these by mistake:https://www.amazon.com/Banana-Female-Binding-Adapter-Connectors/dp/B07C7WG23GSo, what exactly do you use to tighten these things? The fasteners look basically like a "spanner nut", but if that's what they are, does anybody know which spanner nut wrench/socket to use for these? Or are they something else altogether?

author: Gyro
author_rank: Super Contributor
timestamp: July 06, 2021, 10:33:47 am
content: The proper tool looks like a traditional tubular spanner with 2 pips on the end.Depending on how many I'm doing, I normally resort to bodging it with a pair of right angle circlip pliers, the tips of long fine nose piers (held at an angle), or in extreme cases, 'drifting' the nuts round with a flat blade screwdriver in one of the slots. If you have properly shaped the hole with flats, rather than just circular then this is normally sufficient (but messy).

author: jpanhalt
author_rank: Super Contributor
timestamp: July 06, 2021, 10:37:48 am
content: The generic name for the tool is "spanner" wrench. There are several types. A face spanner will work, but I would probably just use a pair of long-nose pliers unless I had a lot of them to tighten. Here is just one link:https://www.aftfasteners.com/spanner-wrenches/EDIT: You can also use snap ring pliers.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: July 06, 2021, 11:05:16 am
content: https://www.warwickts.com/4980/PJP-32973299-Panel-Mount-Banana-Jack-Tool-Kit

author: Gyro
author_rank: Super Contributor
timestamp: July 06, 2021, 11:18:22 am
content: QuoteOuch! I keep meaning to dig out a bit of scrap tube and a file, I just never get around to it at the right time!

author: voltsandjolts
author_rank: Unknown
timestamp: July 06, 2021, 12:05:52 pm
content: Why go for that cheapskate version when you can have deluxe for a mere 70 bucks?https://uk.farnell.com/225071https://www.newark.com/07WX6015

author: Terry Bites
author_rank: Super Contributor
timestamp: July 06, 2021, 03:53:30 pm
content: You beat me too it!

author: jpanhalt
author_rank: Super Contributor
timestamp: July 06, 2021, 05:04:24 pm
content: Guys with the cylinders/sockets: What if a wire is already connected to the tab on the female socket? The question was how to tighten, not remove

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: July 06, 2021, 05:51:09 pm
content: Quote from: jpanhalt on July 06, 2021, 05:04:24 pmCut a slot along the length of the tube, like a cable gland spanner

author: ChuckDarwin
author_rank: Regular Contributor
timestamp: July 07, 2021, 05:45:25 pm
content: For installing un-wired, look for "X-Key Repair Tool" on your favourite auction/low-cost site. Four hollow tubes of differing sizes with fingers arranged in an X, about $10USD. One tube on mine fits 2mm jacks nicely and a larger tube with 2 of the 4 fingers filed off does the 4mm well. The key works well for a base platform to modify as needed For pre-wired, I use 90-degree bent smooth needle nose pliers that I have angled the tips in slightly for better purchase. They get the job done without too much fuss.

author: Gyro
author_rank: Super Contributor
timestamp: July 07, 2021, 06:09:38 pm
content: That's more like it. More the sort of price where it isn't worth the time to make one.

author: HighVoltage
author_rank: Super Contributor
timestamp: July 07, 2021, 06:22:57 pm
content: Quote from: ChuckDarwin on July 07, 2021, 05:45:25 pmI had no idea that there was such low cost toolThanks

author: Fraser
author_rank: Super Contributor
timestamp: July 07, 2021, 07:24:41 pm
content: I had seen the tool for mobile radio use but forgot about it. EBay have a good choice. I went for a decent quality example rather than the cheapest. Cost was £7.99 delivered in the UK in 3 days. Not bad for a specialist toolChuckDarwin, thanks for mentioning the X—Key tool

author: David Hess
author_rank: Super Contributor
timestamp: July 07, 2021, 07:38:17 pm
content: I always end up using either pliers to grip the nut at right angles, or my longest needle nose pliers as a spanner.

author: mindcrime
author_rank: Unknown
timestamp: July 08, 2021, 11:48:15 am
content: Quote from: ChuckDarwin on July 07, 2021, 05:45:25 pmAwesome, thanks. Found and ordered an "X-Key Repair Tool". I feel better now knowing that I have a (more or less) proper tool for working with these things. I'll probably still mostly favor the hex-nut ones, but since I have a bag of these other ones lying around now, might as well use them at some point.

author: Fraser
author_rank: Super Contributor
timestamp: July 08, 2021, 11:57:29 am
content: I recently purchased some of these 4mm sockets for shrouded plugs as I have a small project that needs this type. I did read somewhere that they can be quite fragile though and the centre insulator can shear away from the rest of the socket. The plastic does look to be a brittle type so I think care is needed when using these particular sockets. More expensive sockets from the likes ofMultiCompMultiContact use a softer plastic that is more resilient.

author: HighVoltage
author_rank: Super Contributor
timestamp: July 08, 2021, 01:40:31 pm
content: Quote from: Fraser on July 08, 2021, 11:57:29 amFor this reason, only use these sockets from MultiContact (Stäubli), Made in Germany.The quality is so much better than the China copies.

author: tooki
author_rank: Super Contributor
timestamp: July 08, 2021, 05:23:47 pm
content: Quote from: HighVoltage on July 08, 2021, 01:40:31 pmAre those actually manufactured at their German plant? I’m still seeing Switzerland as the country of origin for their test and measurement connectors.

author: tooki
author_rank: Super Contributor
timestamp: July 08, 2021, 05:25:03 pm
content: Quote from: Fraser on July 08, 2021, 11:57:29 amDo you actually mean MultiContact (now Stäubli)? MultiComp is Farnell’s house brand, which could be anything…

author: HighVoltage
author_rank: Super Contributor
timestamp: July 08, 2021, 07:19:35 pm
content: Quote from: tooki on July 08, 2021, 05:23:47 pmStäubli is in more than 20 countries active with manufacturing.But I remember talking to them at a trade show and it seems these contacts are made in the German production plant.However, maybe that has changed.The MC products are of very good quality.

author: Fraser
author_rank: Super Contributor
timestamp: July 08, 2021, 08:38:09 pm
content: TookiSorry, yes... MultiContact.

author: LaserSteve
author_rank: Super Contributor
timestamp: July 10, 2021, 03:09:01 am
content: A Lens Wrench / Optical Spanner is designedto be incredibly adjustable and would make short work of that.

author: wizard69
author_rank: Super Contributor
timestamp: July 13, 2021, 12:05:40 am
content: Quote from: Gyro on July 06, 2021, 10:33:47 amI’ve done all of the above over time. Also the time tested miniature Chanel locks.However if you have access to a lathe and possibly a mill, it is also possible to make a more correct tool. It is a good idea to make friends with somebody that does have such tools.One thing you might hear such special wrenches called is “gland wrench”! The wrenches for working on hydraulic cylinders are very similar in appearance. Tubular spanner wrench is another term. Sometimes these “nuts” can be castellated so castellated spanner is a possibility too. You can also by special adjustable retaining ring wrenches often sold for work in the optical world.

author: perieanuo
author_rank: Frequent Contributor
timestamp: July 13, 2021, 07:28:22 am
content: just use circlip pliers if you got in your mechanical kit, the needed couple is not so big. or any pliersif you want pro solution, buy pro key, let's not overcomplicate a simple matter

author: garytoosweet
author_rank: Contributor
timestamp: May 09, 2025, 02:44:46 pm
content: Sorry to revive this old thread, but this was the best resource I found on the topic when googling it recently.As these nuts seem very popular, I am surprised there is not a readily available economical tool for tightening.I will add that Cal-Test has a relatively new tool, which seems to possibly hold the jack from the front as well (if you don't have a D hole, I suppose).Cal-Test CT2246B. Priced $48USD at Mouser and Digi-Key at time of writing.If I have some time in between projects, I may model a panel wrench to fit these nuts and see if it will be economical to produce a small run. Similar to the one attached, but to fit these nuts. Provides good access when wires are attached.

author: garytoosweet
author_rank: Contributor
timestamp: July 03, 2025, 04:51:11 pm
content: I held off on making the wrench as I picked up a the Mueller tool (BU-31610-X-IT) on clearance for a few dollars.The Mueller is limited to tightening unconnected jacks, you can not use it once a wire is connected. It will also only fit on jacks with short connectors at the back. I have some with longer pins and it can't reach the nut.Here is a panel wrench in stainless steel. Perfect fit where it just grips the nut enough to hold it, but comes off incredibly easy. Of course this will work on wired or unwired connectors, in any configuration. Bent for easy access.I had been looking for a tool like this for awhile, and now I am building a patch bay with many of these connectors so I thought it was worth it to go ahead and make it.I would be able to sell them for $10 at a small profit with a minimum order quantity of 50, but I don't think I'm looking to go into the wrench business. Really useful wrench. Shame you can't get an inexpensive mass produced version.

author: tooki
author_rank: Super Contributor
timestamp: July 03, 2025, 06:17:03 pm
content: Nice!Have you ever seen the special tools made for inserting/removing closely packed BNC connectors (where there’s no room for fingers)? For example, Jonard RBNC-12. TThe same principle, of a longitudinally split socket, could probably be adapted for these things, too.Of course, one can also buy regular hex nuts to go on the back of banana jacks; some manufacturers sell them as accessories.

author: langwadt
author_rank: Super Contributor
timestamp: July 03, 2025, 06:23:21 pm
content: angled inside split ring pliers could also work

author: Roehrenonkel
author_rank: Frequent Contributor
timestamp: July 03, 2025, 07:01:02 pm
content: Hi,i'm using the original Stäubli-tools.