I'm with nick and swing here. i like to hand file the tooth and the drags when they are wood dull or only a tooth or three damaged by rock, dirt, or 'crete. Anything more than that this oregon bench grinder i got is awesome, the big model. kinda high price wise but worth it when i can fix the chain rather than buying new. When i refurbish them i put them into new boxes and do the drags. the guys think they are getting a new chain unless they really eye ball them. We have three full timers and three part timers in this part of the year. I am starting to issue guys their own saws, thus eliminating maintenance issues by singling out the guys that don't know how and/or are to lazy to maintain the saws. Retraining can occur after the problem is diagnosed. The worst guy i had is now the best guy i have, since he can't just put a saw down and grab another. It has also improved their cutting, planning, crew dynamics, and general craftsmanship; thus reducing my maintenance cost. for the record only my permanent/climbers have two saws assigned one top handle, one 24" saw; ground pounders have one small saw 18" assigned. one "big saw" is assigned per truck. employees have to turn in chains to get a new one, turn in old files to get new, turn in old eye protection to get new etc, etc, etc... That way if there is a problem it can be identified early. I have spent hella dough on maintenance this year. it will change next year now that the guys are accountable for the equipment the use.