Try steel wool, like the Brillo pads only without the soap. lol Keeps the pins sharp too. Speaking of pins, when trying to pin material and its stubborn and won't go through, run the pin through your hair and try again. I keep my pins in a magnetic bowl that I got at Harbor Freight for 2.98. I kinda toss the pins towards the bowl and the magnet sucks them up. I have one for my sewing feet that i'm currently using, and one for my metal bobbins.