I use wax on all of my wooden bearing edges everytime I change the heads. It keeps the edge smooth. I use a clear or white large candle. I guess you can just buy paraffin wax, but I just use what I have around and it works fine.
I picked this up in high school, when our teacher, who was a percussionist, taught us how to do routine maintenance on our marching drums. He also suggested we keep the tension rods lubricated with vasoline or another lubricant. I've just always done it that way ever since, every time I change heads.