I have wanted a magnetic knife stand for my Japanese and European knifes for a while now, and although there are many to purchase, they all had one problem: They had to be mounted to a wall or cabinet. Since I am renting, I can not make holes in the walls so those blocks are a no-go.
So I decided to come up with my own design for a magnetic block, but self supported. I made two stands, a large one from Teak (thanks West Wind Hardwood) and another smaller one from Oak. They each have four mortise/tenon joints, and some shaping that I have done with a spokeshave. The main block contains 29 neodymium magnets (rare earth metal alloy Nd2Fe14B) in a staggered pattern consisting of two rows, and the smaller stand has 16 magnets in a grid like pattern across two rows. The magnets are strong enough to hold a large Wa-Deba but not too strong to cause issues with a small pairing knife. I finished them off with Urethane.