I have had this since 12/08 and have not used it more than10 times, but everytime I have used it I have had to spend at least 20 minutes fooling with the plastic part in the handle before it would work. It locks ok, but the plastic piece doesn't seem to snug up at the bottom. I use an eyeglass screwdriver and put it in the opening at the lower part of the handle and push the plastic piece forward. It will work for a few minutes and then I have to do it again.