My scroll saw didn't come with a blower to clear away sawdust. So I made one using a bellows foot pump that I found at a sporting goods store.
The pump is attached to a plywood base next to the saw. An extension arm, secured to the lower arm of my scroll saw, fits over the top of the pump. When operating the saw, the oscillating action of the arm moves the bellows and supplies puffs of air to keep the workpiece clear.