Removing bastard lug nut

[Matt]

Big pair of quality vice grips will get that off....

[stahlz_ae86]

Or an allen key you don't care about cut a piece of hex key 30mm long (has to be oversize) bash it in then use socket to remove maybe...

When metric cap screws are flogged out at work we just use the next size up allen key from the imperial set, tap it in with a hammer then most of the time they undo.

[dying3k]

chisel into the centre then turn it with a shifter

[maxhag]

I had the same style nuts do the same thing. After trying things mentioned already, I eventually made it so i could bash a socket tightly over the outside of the nut and turn it that way (18mm socket from memory)

[macca1590]

if you handy with a welder you could just weld another nut to it, and if you do a good job you can even use it again haha