Chosen Solution
When I brew a normal pot of coffee, the filter basket overflows with coffee and spills all over the place. What am I doing to cause this to happen?
After working through all the usual suspects (coffee grind, filter condition/type, bean variety, the drain hole/trigger in the filter basket, etc.), I converged on this solution. The interior surface of the filter basket has deep ridges on which the filter rests. These ridges create conduits to promote water flow, but coffee oils can cake inside these ridges and prevent water flow. Unfortunately, a standard coffee machine cleaning does nothing to remove these oils. Either elbow grease and a scrub brush or the dishwasher is all that will clean the basket ridges. The basket being black doesn’t help identify the problem, but I noticed when the ridges are clean and free of oil and residue, the ridge surfaces are no longer dull in appearance, rather, they appear glossy.
Your problem could be from using too much coffee grounds, a bad filter and/or too many filters. If you use too much coffee grounds the coffee maker will not brew completely causing it to over flow. If you use a bad filter like a cheap brand filter this will cause an overflow. If you use too many filters the coffee ground won’t brew almost anything causing it to overflow as well.
