It does more than make it hold an edge a little bet longer. It allows the tool to cut 2x3 times more material. Also, The tangential cutting force, point loads and shear do not anywhere's approach what is seen at the tip of the cutting tool which is often in the tens of thousands of kilograms! This is why the coating lasts far longer than the 2 hours you claim. In fact it should double the life of the cassette at a minimum.
It does not prolong anything. Yes - coated tools, tungsten carbide tools, and other more intresting processes allow all that good things. Higher feeds, deeper cuts. But nonetheless once an edge is dull, the tool gets replaced. Whence came replacable milling plates and other things that are meant to allow quick replacements of cutting tools without too much downtime ( some milling centers do it automatically ). Nobody in their right mind expects a cutting tool to last hundreads of hours. Depending on the cutting process a tool might last as little as minutes before being replaced.
A cassette can expect up to 20-25% material loss from teeth when replacement is needed. That is milimeters of material shaved off when all the fancy coatings add microns. The coatings add
nothing to longevity of the cassette.
And we totally gloss over the fact that cassettes are made of softer steel then cutting tools. Even the most mundane high speed steel is over 60HRC hardness, while cassettes top at about 40.
To say that coatings extend life of a cassette is like saying that you can make one out of wood if you coat it with tungsten carbide.
I thought that for these money it should be solid for years. I'm using MucOff bio degreaser and water.
