R4Dry4 Replacement Knobs

cults3d

When you live on a farm, particularly in areas with snow, a boot dryer is a must! An inexpensive one is the "R4Dry4" which features two knobs that seem to be easily broken (assumption based on the fact that this is our second unit which has had knobs break and I've seen others). Having tried gluing the factory knobs without luck I opted to make my own which were a bit more "hefty". The larger of the two knobs is designed to fit over a shaft with a notch in it. I purposely designed the stem of the knob to have a small groove. I found a piece of hack-saw blade to be about the right thickness of metal to fit in the groove of the switch on the drier. I cut a piece of hacksaw blade off about 1/4" long, held it with a pair of pliers, and heated it with a lighter. When hot I then pushed it down inside the groove on the knob until near the base of the stem (with the front of the knob facing down) and let it cool. Using a thin bit of plastic between the knob and the switch of the boot dryer it created a great friction fit and the piece of metal locks in the slot for firm control. Note: After carefully designing the smaller D-shaped knob I discovered that there is apparently some variation between the switch in some units. This knob fits mine great! the other two I've made not so much. To fix this (they were a hair loose) I simply used some thin plastic bag between the switch and the knob.