Next site, a Douglas fir that the neighbor wants to cut for fear that it will fall on the road on a windy day: you have to aim well so as not to damage other trees located in the least problematic direction ... c 'is a narrow spatial and not temporal "fire window", as this expression is usually used.
The branch will be milled immediately. To this end, I proceeded to sharpen the blades which had "morflé" well, although the walnut branches were rather soft in green and no foreign object had passed through the grinder, but the steel was not is not of a remarkable quality (steel "to shoe the asses" one said formerly!
). With almost certainty, it is a hardened carbon steel, then subjected to a fairly high tempering, which prevents it from being brittle, but its low hardness makes it not very resistant to abrasion and easy to chip.
It would be possible to try a classic tempering with a moderate tempering (straw yellow?) This time, to obtain a superior hold of cut ... It is a rather delicate balance to find between hardness and flexibility, the concern is that it goes very quickly at the decisive moment of income.
Another possibility would be to have alloy steel blades made by a toolmaker: the mixture of additives (chromium, manganese, cobalt, etc.) makes it possible to reconcile hardness, abrasion resistance and flexibility.
They are better than others that I have put on the wire before and that is the best thing I can do with my unintelligent phone ... 
Let's just say it's a slight artistic blur, right? 
