They measure a series of points to get a bed mesh, the same as other leveling sensors do. You shouldn't need to live-adjust z, because you've measured the bed surface with the nozzle tip.
With a BLTouch, you need to adjust the z-offset, because the nozzle tip and the BLTouch trigger height are not the same. Once that is calibrated, it should continue to work fine as long as the sensor is working properly.
I think it mainly comes down to the accuracy of the sensor. If your sensor gives you a +-0.03mm reading when probing the same spot, then you will have high and low spots in your bed mesh that you can't correct with z-offset.
This could explain your issues with the BLTouch you mentioned in another thread here. I have various brands of knockoff BLTouch sensors, and the worst one had a +-0.02mm range when measuring points, which made it impossible to get a good bed mesh. The one I replaced it with had about a +-0.005mm accuracy, which fixed my issues with the low and high spots.
You mean in response to pressure changes during print? I’m not sure but that would be nice!
I do have two BLTouch printers and lots of Prusas with the PINDA inductive sensor. What excites me about direct nozzle force sensing is that it eliminates the need to calibrate z height offset between the sensor and the nozzle. I don’t know if Bambu’s bed sensor is as good as Prusa’s nozzle sensor but anything that eliminates the mechanical stack up between nozzle and sensor is an improvement IMO.
Though I do realize much of my gripes come from the fact that the PINDA mount on the Prusa Mk3s is kinda weak and I’ve had several fail, requiring an annoying service job.
stavros|2 years ago
jyxent|2 years ago
With a BLTouch, you need to adjust the z-offset, because the nozzle tip and the BLTouch trigger height are not the same. Once that is calibrated, it should continue to work fine as long as the sensor is working properly.
I think it mainly comes down to the accuracy of the sensor. If your sensor gives you a +-0.03mm reading when probing the same spot, then you will have high and low spots in your bed mesh that you can't correct with z-offset.
This could explain your issues with the BLTouch you mentioned in another thread here. I have various brands of knockoff BLTouch sensors, and the worst one had a +-0.02mm range when measuring points, which made it impossible to get a good bed mesh. The one I replaced it with had about a +-0.005mm accuracy, which fixed my issues with the low and high spots.
TaylorAlexander|2 years ago
I do have two BLTouch printers and lots of Prusas with the PINDA inductive sensor. What excites me about direct nozzle force sensing is that it eliminates the need to calibrate z height offset between the sensor and the nozzle. I don’t know if Bambu’s bed sensor is as good as Prusa’s nozzle sensor but anything that eliminates the mechanical stack up between nozzle and sensor is an improvement IMO.
Though I do realize much of my gripes come from the fact that the PINDA mount on the Prusa Mk3s is kinda weak and I’ve had several fail, requiring an annoying service job.