Our Samsung DW80F600 dishwasher has not been cleaning the greatest lately. Plenty of pressure as when I open the door it sprays water everywhere if I open it too fast. However I noticed that everytime I open the door the bottom sweep arm is in the same place. Looking closer I see that the arm is rubbing and apparently getting stuck on the door. Photo below shows the marks from it rubbing. Click the image to see it at a larger size:
Any idea how or why this would happen? Better question, how do I fix it? It's three years old and out of warranty, so for a moment I actually considered striking that spot with a hammer lightly to try to push it in enough to allow the arm to pass. Either that or taking a file and shaving off just the very tip of the arm. Hopefully someone here has a less brute force method of fixing it. Any ideas?