Surface > creates a along the intersection of two surfaces, which could later be used for trimming for instance.
More information and problem solving on the Intersect Surfaces command
The same problem with precision or tolerance as with Trim may arise with Intersect Surfaces.
Solution: You can increase the tolerance in the Options of the Intersect Surfaces Tool. A smaller number will result in a higher precision and may be required when intersecting small surfaces. Another solution is to increase the overall scale of your objects.
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