Ashley A Anchorage , AK December 28, 2014 Appliance: Whirlpool 4 1/2 Qt. Stand Mixer Classic - Tilt K45SSWH-0 My kitchenaid was missing the back cover (received it like that for free!) and the thumb screw was broken I simply replaced the back cover, it only took 1 screw. Then I replaced the thumb screw as well. It took less than 5 minutes. Read More... Do-It-Yourself Rating: Repair Time Estimate: Less than 15 minutes Tools: Screwdrivers