edge allignment

so i started using blender today and now i’m busy for at least 2 hours trying to allign a cilinder (8 vertices, flattened, widened, lengthened) to a cone (8 vertices, , flattened, widened, lengthened), but i keep having slightly unaligned edge.

i was planning to learn to make some basic objects by this midday, but i’m a perfectionist and now stuck on making a sword (the pieces are supposed to become the blade)

thanks in advance

Aonir

screenshots/.blend please!!!


this tiny edge is the problem.