Methods and systems are disclosed for characterizing a welding consumable, such as flux or an electrode, and/or for comparing two or more welding consumables for use in narrow gap deep groove welding operations, including creating test welds on fixtures having joint grooves of various angles for a given groove depth, followed by controlled standardized non-aggressive slag removal operations, and quantification of the amount of slag remaining in the groove, wherein the welding consumables are each characterized using the same fixtures, welding conditions, workpiece groove depths, groove angles, and removal operations, to construct a set of results, such as a table or rating, by which the individual welding consumables can be rated and/or a determination can be made as to which of two consumables provides superior performance with respect to ease of removal in deep groove welding operations.