i clean the inside of my dies on a regular basis, esp FL and body dies. bullet seating dies are cleaned less often, but attention is paid to the bullet seating stem. recently i noted i was having trouble seeing the very close together hash marks on a redding bullet seating die. i have some whidden micro seaters and their marks are BIG and can be seen from across the shop. i decided to get a very fine tip white marking pen and re color the hash marks on the redding as i figured they were worn from years of use. well, to my surprise, the hash marks were not worn off, but were VERY DIRTY! to adjust the reddicng your fingers contact the marks but not so on the whidden of forster microseater...the marks on the latter are very fine and hard for me to see so i was going to mark them a bit wider with the same pen. i used a fine pick to remove the oily dirt, etc from the hash marks and...i can see them again. learning something new every day...