First time balancing a prop. I sanded the back of the heavy end of an APC 11 x 5 which was hanging at 6:00. Now the original light end (OLE) is doing some weird things. I positioned the prop at every point of the clock and here is what the OLE moved to:

Starting Position Ending Position
12:00 1:00
1:00 1:00
2:00 4:00
3:00 4:00
4:00 4:00
5:00 4:00
6:00 4:00
7:00 4:00
8:00 4:00
9:00 4:00
10:00 1:00
11:00 1:00

Then I spun the prop clockwise three time and the OLE ended up at 4:00, 2:00 and 10:00 respectively. When I spun the prop counterclockwise the OLE ended up at 4:00 all three times.

What is going on and what can I do?