Min Time
The following are min working timers (using food or spells) in seconds:
Combat: 2 between hits
After a kill: 5
Before first hit: 7, unless shock or chain lightning is used
Construction
Sawing logs: 10
Sawing logs at hikori: 15
Sawing hardwood: 10
Adding lumber, stone, bars etc.: 15
Repair houses: 15
Shelving: 30
Cooking (everything): 20
Crafting:
Making glass: 10
Great Staff: 20
Everything else: 25
Fishing: 15
Making bait: 10 (used to be based on level only, but food can be used)
Harvesting
Planting: (all crops): 15
Picking (all crops): 15
Filling Bottles: 15
Grinding Wheat or Sugarcane: 15
Making Plant Food: 10 (based on level)
Magic
Training or Casting 1 spell: 15
Multi-casting: 15 + (15 +3) x (Quantity of spells casted – 1)
or: 18 x Quantity of spells casted – 3
Mining: 15
Smithing
Smelting: 10
Smithing: 15
Speed: 15
Woodcutting: 15
Information courtesy of The Forsworn (: