John: I just replaced 3 caster from a Colson truck with maroon casters. One of them cracked. The rubber came appart. From what I can gather, the truck was only about 10 years old, and held a 6' Howard. I talked with Dave Johnson at Schaff and he told me that the maroon casters have been know to break appart. I replaced the caster with new ones from a caster company in St. Louis. These were black rubber, which is much harder, and as a result, the piano rolled better. When I played it, however, th epiano stayed in place. If this is not enough, you could always get casters with brakes on them. Wim.
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