Removing broken BFA from terminal on Luxman M700u amp

How it happened, I have no idea but the BFA banana plug on one of my Luxman M700u amp terminals broke off inside the terminal. I cannot get a a grip on it. I’ve talked with Jeff at Luxman and he recommended: a) using a suitable sized wooden dowel to engage the broken piece and pull it out - this didn’t work; b) take the unit to a local audio service center (I’d prefer not to do this as the M700u gets heavier with every senior year that passes); and c) switch to spade terminals leaving the broken BFA plug where it is. Jeff recommended NOT to unscrew the terminal as this would make it nonfunctional.
Anyone else had this issue and solved it?

Mike

Can you post a pic of the terminal on the amp? Is there any of it sticking out that a pair of needle nose pliers might be able to grab?

From looking at the photo the red plug is hanging by a thread!!

Unfortunately not - I think that the break has left an ‘edge’ on the embedded piece which is occluded by the terminal screw that prevents any movement of the broken end. I also suspect that the wooden dowel approach has pushed the broken piece further in. The saving grace is that I can use spades to attach speaker wires.

Can you fashion a small hook of some type and try to snag it and then pull it out?

Mark
Tried several pointed/hooked tools - they would not engage the broken tip. Saw some hooks to remove broken keys on You Tube which may work. Going to call Mike Morrow who made the speaker cables to see if he may have any suggestions.
Mike

Whether or not this would work will depend on how the tool fits in the broken banana connector, but it’s what I’d try first. If the tap cutter fits just right, it should grab the inside of the banana and let you pull it out. A TINY bit of penetrating oil applied on the outer perimeter of the banana might reduce extraction friction. This would definitely take touch with “finesse,” you don’t want to expand the banana but you have to get it to bite in a little.

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Photon
This is a good suggestion - what was the source of the attachment?
Mike

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That was just a screen grab of the first good example I saw in the web, those are some cheap Chinese stuff from Alibaba, You can find those cutter taps in just about any hardware store. The outside diameter of the BFA banana is 4mm so either a 3 or 3.5mm tap would be the ones to try as I couldn’t find any specs on the inside diameter of the BFAs.

https://www.homedepot.com/p/Drill-America-m3-5-x-0-6-High-Speed-Steel-Tap-and-2-90-mm-Drill-Bit-Set-2-Piece-POUM3-5X-6/304746964?source=shoppingads&locale=en-US&pla&mtc=SHOPPING-BF-CDP-GGL-D25P-025_007_POWER_TOOL_ACCESSORIES-NA-Multi-NA-PMAX-NA-NA-NA-NA-NBR-NA-NA-NA-Power_Tool_Accessories2024_EXISTING_BHU24&cm_mmc=SHOPPING-BF-CDP-GGL-D25P-025_007_POWER_TOOL_ACCESSORIES-NA-Multi-NA-PMAX-NA-NA-NA-NA-NBR-NA-NA-NA-Power_Tool_Accessories2024_EXISTING_BHU24-71700000114565633–&gad_source=1&gclid=Cj0KCQjw3ZayBhDRARIsAPWzx8rkUzFPR0AfAYw10TQ4mUXzKXTLXz2jyCeYnT0XfI-k8PMZ1w54RJ4aAl9EEALw_wcB&gclsrc=aw.ds

The other thing to be careful of is whether there’s any bent metal obstructing the entrance of the cutter. If there is, you either have to clear it with a smaller cutter that will pass through or a drill.

Thank you for the info and for the warning - I think there may be bent metal in the terminal where the BFA broke off.
BTW - do you have any recommendation for spade terminals that don’t require soldering? I’ve looked high and low. Pangea has an interesting spade terminal as does Viborg on Amazon. The latter looks well made but there are very few reviews.

As to non-solder spades, I can highly recommend Furutech’s offerings. Either the FP-201 series or the FT-211 series can be used without soldering. I put together a set of cables with the FT-211s and they are very high quality, a joy to use. For the safest connection with the least likelihood of damaging the cable, I used gold plated WBT sleeves before assembling the cables. I also rented his WBT 0403 sleeve crimp pliers to do the job as they crimp a better pattern than most crimp pliers. (See the link to “crimping instructions” above the entry for the Furutech connectors.) Some people claim that the crimp sleeves adversely affect ultimate sound quality but I’ve never done an A/B comparison myself.

https://www.vhaudio.com/connectors-speaker.html#spade

Try an EZ out

IMG_0554

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The Furutech 201s look perfect for my needs - how do you measure the speaker cable to get the correct size WBT sleeve?

Is the banana pushed in far enough to have room for another one to fit behind it?

Or maybe this…

John 2213 is right, an EZ out is probably an even better idea. I forgot about those, it’s been many years since I’ve turned any wrenches.

As to what size crimp sleeve to use, most cable manufactures specify what the diameter of their wires are. I had bought my Furutech speaker cable from Chris Venhaus as well so I just asked him what to buy and he figured out the best one for me.

https://metersuk.co.uk/american-wire-gauge-awg-cable-conductor-sizes/

Unfortunately not

Best advice yet, this is The Way.