Hi Dennis,
I did not feel any ridging on the base, but you got me thinking, i get what you mean, if the column is leaning back or forward then it will create a saw tooth effect. I was real careful not to apply and directional force to the column when adding the support plate but this is a great tip, many thanks Dennis and something i will double check.
Each pass was in opposing directions so maybe the stripey effect in the pic is because of this, probabaly the wrong way to mill?
Many thanks
Ade