Use this to sharpen your dull 28mm straight rotary blades.
28mm Rotary Blade Sharpener, Colonial Needle
Rotary Blade Sharpener 60mm
Rotary Blade Sharpener - Stitch and Go
Olfa 28mm Rotary Blades - 2 Piece - Juki Junkies
28mm Rotary Blade Sharpener, Colonial Needle : Sewing Parts Online
SCISSORS-ROTARY CUTTERS-BLADES
Rotary Blade Sharpener, 28mm & 45mm
TrueSharp Power Rotary Blade Sharpener 088167 for sale online
Colonial Dual Rotary Blade Sharpener 28mm - 707285357286