Are there any wool spinners out there who use a box type Wool picker who could help me. I am constructing one at the moment and would appreciate information about the nail distribution from someone who has got one. I think I need to know the number of rows of nails, direction and angle also the distance between the nails and between rows. For both the top and bottom pieces. I assume the nails in the top piece pass between the bottom nails so they don't lock together but I can't see from pictures by how much they overlap. I have looked at pictures online and probably any guess I make won't be too far out. But I would have more confidence about it if I knew the dimensions weren't too far out.Is there any advantage in having the nail sets removable to adjust how agressively it works?