I made a wall mounted knife bar. I used some strong neodymium bar magnets. Even so, for the proper pull strength, I had to route down so that there was about 1/8" thickness. If you're going to point the knives down, you might not need as much pull, as the handle/bolster will aid slippage (funny thing that I found is that the small knives are actually more problematic than the biggin's).