Band Problems

[flattail]

I bought some new Cooks blades but they won't stay on the band wheels.I put a resharp different brand band and all was good.What am I doing wrong?The only difference between the two are a thousandth thicker Cooks band.Help!!!!!

[4x4American]

Did you only try one Cook's blade?

[kelLOGg]

When I change band brands I find I have to re-adjust tracking.
Bob