I used the mobile home axle. In the thread CYJ mentioned length of the arms. The longer the better.

My first attempt I had 15' arms for a 30' circle. That was way small. The dog could not open up and run as well because he was in a sharper turn. I added about 9' to each side (ran out of room) and it was much better. I wish I could have went out even further.

I miss using it. My land is on a slope and that was about the flattest spot I had. I ended up having to decide between the jenny and my shop. The shop won out.

EWO