Possible Clues:

• One sort of saw double figures on this
• Saw to it that there was a number on it
• Shaped end of piece of wood for slotting into a hole.
• For this there's more - 'tis thesound of it
• Part of joint a music group set up
• Joint part (with mortise)
• A number working to secure projection
• Wood-joint feature
• Almost all the eleven working in a joint
• Not one comes back on time to make the joint