G'day
For the most part I found that video to be informative, it was a basic explanation of how to do this for yourself at home, a repair shop would never have the time to sharpen chains by hand as often you have people like wood cutters that drop off many chains at the same time, its quicker when they are out cutting fire wood for these guys to fit another chain rather than stop to sharpen one, also keep in mind a lot of the American woods that you see them cutting are soft woods like pine, they don't have jarrah, and tuart,etc. and some of the other super hard woods that we get here, and also I have had chains to sharpen from Alaskan mills that are used for cutting slabs of wood, these can run 6+ foot bars so you can imagine how many cutting teeth are in a six foot chain, simply not viable to do it by hand, and the guys that use these things are super critical about the way the chain is sharpened as well so they are machine sharpened and it is very important to have the angle and pitch correct as per the chain manufacturers specifications for optimum performance.
On the point of angles and pitch of the chain, he says that it is not important what angle the tooth is sharpened on as long as they are all the same, that is not really correct as there are several types of chain types and for them to perform correctly they need to be on the correct angle and pitch, chains are designed to be better suited for cutting either soft or hard woods or dry and wet woods, professional type saws are sold with higher performance chains like the semi chisel and full chisel chains they perform better with the cutting tooth angle like 25 deg and 10 deg pitch, or 30 deg and 90 deg pitch for instance where your chains for domestic saw users are more often 35 deg and 90 deg pitch are are more likely to recommended, there are too many types of chain to explain here but suffice to say its important if you want performance and longevity its always best practice to follow the manufactures recommendations when sharpening them.
It is extremely important to have the teeth on both sides the same length, to make the saw cut straight and so as to not cause premature bar wear, if you cant achieve this by hand and the chain still has some life left in it then you are better to take it in to a shop and have it machine sharpened, that will correct all the angles and lengths of the cutters and will give you some further use out of the chain, for the occasional user of a saw around the yard or the odd trailer of fire wood if you are not interested in doing it your self then just take it into a shop and have them do it.
On the subject of rakers, he says that he does not use a raker file gauge, while for the experienced chain saw user that is well and good, but as I have seen for myself its far too easy for people to be tempted to take too many strokes of the file and take them down too far, sometimes more is not going to be better, the raker gauge wont allow you to take off more than is necessary its a boofhead proof type of tool so I would be saying use it if you have it.
cheers
stayyerAU
