Don't know if any of you have figure this out yet but having the same problem, I started taking the tool apart and found that the problem is associated with a set nut found under the cap of the adjustment knob. I noticed a slot on the cap where a flat screwdriver could be used to pry the cap off (go slow and work it up evenly. With the cap off you will see a nut threaded on the travel post for the front foot. Loosening the nut will lower the foot relative to the blade and back foot. Tightening will raise the foot. Once adjusted replace the cap. Note that the cap interior is shaped to receive the nut so that the nut rotates with the rotation of the knob.
