This stud broke last week and I’d like to try and fix it. The stud is for an electrical connection and has an M5 thread.
I was wondering whether it would be possible to drill and tap the broken bit and put a new [m5 bolt with the head cut off] in?

Or maybe put the nut in place and epoxy all around around it and then put an M5 bolt into the top of it to hold the electrical connection.

what’s underneath it?

if it’s just a moulded in bolt or a stud and nut can you just remove the lot and replace?

as above, Id drill a small hole through the back assuming it’s not a problem, drift out the stud head, and glue a new M5 bolt in

Ah, should have said…. no the lower part is moulded in with no chance of access from the other side.
It’s one of these:

I have asked the manufacturers if it’s a warranty claim as it was brand new and I’m not sure it should have snapped – but they may tell me to trot on.

I’d be worried that there’s the same arrangement on the other side (ie a threaded connection with nut on it. If you try and drill it out you’ll loosen that as well.

This sort of thing;

btw, did it specify a torque setting for the nut?

Drill it and you risk damaging whatever is underneath. I doubt there will be a load of excess metal. I’d get back to the manufacturer (or actually the supplier) if it is new and kick up a bit more fuss. If they still say jog on then I’d either look to open it up, but you’ll lose the IP rating. It may well be welded or full of potting compound so that might not work. Failing that I’d make up a bracket that attaches to the other mounting holes to push down on the contact

is there enough thread left to get a nut on? Looks like there might be. Put a long sleeve nut on then a bolt into that for the electrical connection?

No, thread’s all come off – broke just under the thread.

Drill a pilot hole and put a self tapping screw in with a washer (short screw) and capture the connecting wire under the washer?

solder a tag onto it for a spade terminal? Or just solder a wire onto it?

http://uk.rs-online.com/web/p/solder-tab-terminals/0534929/

65A continuous 115A max cable is likely to be fairly large I’d have thought and also that’s a fairly large current?

If it were me I’d be looking for a fairly chunky and robust connection – I’m nit sure soldering would be that secure on it’s own?

Could you contact a local engineering/fabrication company and see if they could weld a new M5 stud on without damaging the surrounding plastic?

wwaswas

I didn’t realise the current was that big. solder is not a good idea nor any of the other suggestions for that level of current

I’d be looking to try to drill/tap the knackered bolt, screw in a bolt and use this to wiggle out the broken bit, then just glue in a new bolt. If that makes sense.

Yes I think a mechanical fix is the way forwards – welding would blow the internal electronics.