Waldemar showed us how to do Celtic knotwork. First you lay down a grid of dots and after that- well- I couldn't actually follow his instructions. There may be a system but it's tricky and sometimes even the original artists fucked up- as on a gravestone on the Isle of Man where the sculpted weave starts out confidently then gets wonkier and wonkier as the artist loses the thread.
Also he showed us how to make an Anglo Saxon brooch- or rather he got the forger Shaun Greenhalgh to show us- in his garage- in Bolton. Sean is a wonder-worker who has forged everything from Assyrian bas reliefs to Monets. He's amazing. Someone give him his own show, please.