I just received this unit and the ordering, shipping and assembly went very well, but I would agree that there should be at least some assembly instructions, over and above the exploded parts diagram, for purchasers new to the equipment. The manual instructions do specify checking the blade gap (0.5 mm) prior to using, which I did with a feeler gauge and I checked that all of the fasteners on the blades and counter blade were "fixed", as per the manual, but there is no torque specification provided in the manual. Since the gap was correct, I did not loosen any of the mounting bolts, just confirmed that they were "fixed". The instructions also specify to recheck that all bolts are "tightened properly" after 1 hour of use.
Well, I only made it about 30 minutes when I was feeding a 3" diam. piece of green maple, the machine was bogging down as it drew the limb in, and then one of the blades broke, releasing a large chunk of metal into the cutting mechanism, chipping the second blade and nicking the counter blade and rotor that the blades are mounted to. :( Upon inspection it looked like the counter blade might have moved slightly, but the gap was still within 1 mm, which I doubt should result in a broken blade and the resulting carnage inside the machine. There was absolutely no foreign material or rocks, etc. on the branches that I was chipping. In the end I was able to flip the blades and counter blade and continue, but I would say that this was a very rough start with a piece of equipment that I had been excited to use, and now the rotor of my nice new piece of equipment is chipped and banged up from the metal released from the blade.
After restarting, the chipper performed reasonably well with maple up to 2 1/2" to 3", noticeably struggling with the thicker pieces. I am doubtful that it would handle hardwood in excess if 3", without experiencing considerable strain on the cutting system and the engine, and I would be reluctant to try. Not sure about soft wood.
In conclusion, there should definitely be assembly instructions. Even a Youtube video would be better than nothing. There should be instructions on how to measure and adjust blade gaps and how to replace/flip the blades, including torque specifications for the blade and counter blade mounting bolts. All of this information is provided by other wood chipper manufacturers.
I've ordered new knives, and I will keep my fingers crossed that my first experience with this wood chipper is not something that will be a regular occurrence.