Just bought the P1S as my first printer a few days ago. It’s printing great and have had no issues except for this off bang/thump noise when it seems to clean the nozzle that just seems out of place. Is this normal?
I hear you, and I hear that! Same thing on my P2S, scared me the first time I heard it! no I just ignore it. Same thing with the melody tones everytime the print starts, finishes, or encounters some error. I can turn that off, but still, none of my other printers make that noise, and it is L O U D!
Yeah. My X1C (which is very similar to the P1’s mechanics) really bangs around at the start of a print. Not sure what it’s doing. Always assumed it was just re-homing or something.
The printer finds it’s XY home point, as well as the limits of travel in either direction, by driving the printhead in to a corner and watching for the stepper motor current to go up (which indicates the motor is stalled).
I think it could do it quieter, but I think it’d have to do it much slower. Might be something in the startup code you could modify if the banging really gets to you.
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Normal.
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Wow! They don’t have limit switches? they depend on current increases to determine the end of travel?
It doesn’t help that the enclosure makes it act as an echo chamber.
Thats the direction most printers are going, especially corexy. Try to find a Z limit switch on any modern printer. Youll only find x and y on cartesian.
So, what you are saying is that since this happens every time a print starts, there will be excessive wear on the motors due to higher than normal current draw? Seems to me that since on all axis, there is a finite stopping point, and a simple cheap(a few cents compared to a few dollars for a stepper motor) limit switch can’t be used? Even my cheaply designed Creality had limit switches.
Limit switches’ travel are orders of magnitude less accurate than a flat plane physically contacting another known flat plane. If you tear into the code, they [sometimes/always/idk, you audit it if concerned] limit current to the motors when doing this tapping. Marlin M17 gcode
No, this doesn’t increase the wear on the motor at all. It’s quite common. The system is “current limited” so the motor doesn’t overheat and burn out. Whatever is getting banged in to might wear out because it’s getting banged in to is all. And it’d probably take a pretty long time to produce any appreciable wear.
Switches will do the same thing for end stops. But they won’t do it better. And they’re extra parts that add cost and reduce long term reliability. Sensing with the motor itself is actually a pretty good solution. Everything you need is already there. The circuitry lets you detect if the motor jams during a print, too. Limit switches won’t tell you the gantry isn’t moving anymore but motor current will.
The mechanics of these printers are pretty precise, but they’re far from “precision grade” equipment. The costs limit how repeatable the system can be. Otherwise, the printer wouldn’t need to do a calibration more than once in its lifetime. The changes that happen aren’t big, but there are going to be changes (we push and pull on the build platform between each print, too, which is why the printer probes Z for each print as well as doing the XY thing).
So the printer really has to do these things with each new print job to be certain nothing has moved since the last job. And doing it electronically instead of with switches is a cost optimization with no negative tradeoff other than an increase in noise when the limit is being detected. 
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Don’t worry at all. My p2s does it and I discovered that it does it when it is homing the axis
The video provided by the OP is not the homing procedure. It shows the print head cleaning the nozzle and then (bang/thump) operating the flapper to clear the poop chute. The bang/thump is normal.
Homing is a much quieter process, as the head finds its limits with relatively gentle taps.
Click “Home” to see and hear the difference.
The sound is normal. Concerned me at first too but learned it normal.
The system is an echo chamber with thin walls and no insulation. The filament wiper, sudden jerk of back n forth, cable above extruder, etc all make it sound like its gonna crash. Nothing to be concerned about and it’s the same for all enclose BL printers.