My Dad made one similar in the 1920's. Ordered a mandrel from Monkey Wards and made the frame from galvanized windmill iron. The mandrel has babbit bearings with oil slots on the top of the housing.
We staked it down when I was a kid, but later we mounted it right to the back of the B Farmall so it can be easily moved.
It's still at the farm; my brother uses it every year.