Wet felted ball 2.5cm. Although soft enough, the merino wool is so densely meshed together that it gets a bit difficult to needle felt onto the ball. Naturally, when you needle felt, the wool will not stop your needle from penetrating through. With the wet felted ball, the needle stops approx. 0.5cm into the wet felted wool and I can't seem to needle felt onto it. Thanks to asherjasper from etsy who mentioned needle felting onto wet felted stuff, especially round 3D objects, is not a good idea as it doesn't needle felt well. Prompted me to try wet felting and experiment needle felting onto wet felted round objects.
This is just a little experiment I decided to try. I wanted to make needle felted Onigiri so I roughly needle felted it to that shape and wet felted it. It shrunk but it didn't really work like the wet felted ball. You can also see some pilling (little lumps) on the top left of the "onigiri". Fail!