LumberMaster
ArboristSite Lurker
Don't worry Matt,
I feel no shame in posting on old threads no matter how old they are. x10 If I found the thread by searching and had something worth adding to it. Maybe be of no use at all to the OP, but it helps build up the knowledge base
FWIW, I've never had much luck with chainsaw sharpening machines. I've never owned one, But I've used a few of the pricier ones. I just find them to be like most types of sharpening; too coarse, too fast, too little control and too hot.
I've been sharpening blades of all types (knives, scissors, drill bits, planes, chisels etc etc) for since I was a teenager and now do it professionally. I have a few different machines for different purposes but almost all are slow (less than 90rpm) and almost all are immersed in water baths (except leather buffs). If you are heating any edge beyond the point where you could comfortable touch it with your bare hands then you are affecting the temper. If you're getting a sizzle when dipping in water then you've gone way too far. If you get blueing, you deserve to be slapped.
In any sharpening process, once you have your stone grit, speed and temperature right it all comes down to the precision with which you can present the edge to the stone, and manipulate it to maintain geometry. Consistency is critical, and the ability to adjust in small (say, half degree or less) increments is important. With most of my straight edge sharpening equipment I can consistently sharpen a blade within 1/4 of a degree, taking off less metal than can be measured with a micrometer. I can get the same edge every single time, consistent along the entire blade length and the metal is likely to get cooler rather than hotter during the sharpening. It generally starts at room temperature and might drop by 2-3 degrees during sharpening.
Sometimes geometry is simple, like a planer blade. Sometimes a little more complex, like a drill bit. I think saw cutter geometry is sufficiently complex that you won't find a reasonably priced machine that will do it. Access to the cutter face is slightly tricky. The variables are the profile of the cutter (hollow ground), the height of the stone/file on the tooth in profile, the vertical angle (should be flat) and the horizontal angle (varies with intended use of the saw). On top of this you want to ideally make each tooth even in size. We'll leave raker geometry out just to keep it simple!
For a machine to do all of these consistently, it wont be cheap. It's hard to envision anything in the sub $1000 class fulfilling all of the requirements. I'd be interested to see how the manufacturers do it.
For me, the only thing that will come close is.... a handfile.
I agree there's nothing wrong with posting on old threads. All the more knowledge we share, the better off we are from others' experience..so we don't make the same mistakes. Thank you, everyone, for posting additional information.
