Dragons Crown, North and West Tunnel

You get 5 characters online, open the console and...
bind space mine_up

Then bash the living daylights out of the keyboard, click the next client, bash again, repeat until all 5 actions queues are full.
When you need more space to mine, drag the ore into the waiting pre-lit forge and bash again.
When the forge is full of lumps, drag them to a waiting bsb.

Works with all veins, apart from slate and marble, and possibly sandstone if they fix it.
It's also handy to have a crate of logs to keep the forge lit for the few hours it takes.