The smoothness of a dob mount depends upon the amount of force on the bearings. You are problably having the major troubles with the up/down motion and that can be fixed by moving the pads closer together for a more slippery motion with less force while further apart will make the force needed to move the scope higher.
The left/right bearings are a bit more difficult and the thing here is that the bearings need to be the right size, out near the edges of the baseboard and that the center pin can't be pulling the rocker box to the baseboard.
In addition, the materials used can make a big difference in the feel of the scope, the knobby type formica being about the best to run against the teflon of the bearing blocks.
I'll also note that dirt can make the motions very stiff so an occasional cleaning of the blocks is in order.
Hope this helps and if you need more info, feel free to ask.