Hi, I'm in the process of doing some servicing on my Entec, ser no CH25PH77030297 and have managed to get 6 of the roller blades off one roller and am now struggling with the second roller!  Lots of drilling and tapping is going to be required I think!  I'm going to get the blades sharpened but would like to know if there is a min length that they should not be sharpened past and indeed, what the correct angle is for them.   Also, I've cleaned out the old grease from the roller assembl