just get some 4 x 18 sanding belts and using a 4.5 inch cut off wheel cut them into 1/2 strips....at HF you can get 6 of them( 1/2 inch strips ) for 4.99// or but a set of 4 x18 inch belts for 4.99.. and when you cut them you now have 18 of the 1/2 x 18 inch strips 
