Three months is the recommended timeframe between concrete chipping sessions. Otherwise you risk excessive buildup which could damage your vehicles and lead to heftier chipping costs.
A cement mixer truck drum rated for 10 yards of concrete can actually hold approximately 14 yards total. Still, it should never be filled past the 10-yard line. The extra space allows for easy mixing and wards off issues such as clumped ingredients and inconsistent blends.
Chipping appointments vary from job to job, but a solid guideline is to book a 12-hour window to ensure enough time to the job done.