Possible Clues:

• Commercials, we hear, for a woodcutter
• Tool with a curved blade
• Sounds as if one puts on more to give it a 3 down
• Tool found in dead zebra
• Tool that cuts and increases, we hear
• It might help you dress in a shop
• A woodworker wields it
• 'Puts on more with a chopper, by the sound of it (4)'
• Tool improves things for the listener
• Lumber tool