The 4 point calibration has been done a few times without any issues. Repeating this, the head comes down onto a piece of paper with just enough z height to just barely hold the paper in place. How is it possible for the printer head to go past the bed height and drill a hole in the bed. Needless to say, it’s unfortunate this is possible, and if I wasn’t present and watching, I’m sure it would have dug into the bed all the way. I stopped the print, reset the head to “HOME” and restarted the print. Still having issues getting the filament to properly adhere to the base at all times and it often creates a mess, but that’s a different issue for another thread. For now, wondering if there should be protection mechanisms in place to not let the printer to self damage itself. Has anyone seen this?
I can’t program in any code, but as far as I understand coding, this can be solved pretty easily !
Coding / programming is about parameters. Parameters (or anything what you can call all those different numbers while printing/carving etc etc) will fluctuate every 0.5 seconds or faster. There could be a kind of alarm when the force on a linear module is increasing fast + when the cnc mill or 3d printhead is turning a different speed or temperature then it is programmed to do, it will stop and returning it’s position to a zero-collision area
I believe in SnapMaker that this error could be solved with a firmware update… Very unfortunate your bed is damaged 
Thank god this didn’t happen to me, yet. Still it really is an issue and I second the automatic emergency shutdown on overload in any of the steppers. You can easily measure the load on a stepper via current-monitoring.
Yet I doubt there is a pure “firmware” way to fix this issue. You would need a sensing circuit for every individual Stepper OR you would have to somehow monitor the overall power consumption of the printer, whereas this solution might be a little inaccurate and might stop the printer during fast movement and/or CNC drilling without a reason.
I agree with needing something with current monitoring. There should be no reason for this to happen. There is a chance that by the time the stepper load changes though the damage is already done. Is there anyone at Snapmaker tracking these issues, I’d be curious to get the designers thoughts on this. If this is a bug that you expect to never happen again with improved firmware / controls, that’s an approach. Can a strain gauge concept be used to detect ANY upward pressure on the head to auto cut off the linears before damage is done?
Also, would love to trade heating beds and ship this one back.
I have used CNC mill’s and when setting up your offsets you can always jog the spindle as you are setting your offsets. It would be nice to have that ability so we can jog the Z axis up from axis home before setting Z offset points to insure that we don’t jam the nozzle into the build plate like some already have.
I have noticed that when it does crash into the build plate during recalibrating the z offsets it can bring the build plate out of level and really create some frustration.
Firmware is exactly where this needs to be addressed.
The machine can not rely on application software to address safety issues, because which application software will be used can not be controlled.
Emergency stop is required for any serious machine, which I believe SnapMaker is designed to be.
Re-settable HOME/STOP on EVERY AXIS is a minimum, to prevent a machine from harming itself, harming user, and/or harming work-piece(s).
A learning curve is to be expected on new designs, and early adopters should be aware of this.
But the design team’s response will basically determine the life span of the product line.
I’ve put in my nickels, and hope to have a long term relationship…
time will tell…
william…
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I assembled the machine according to the Quick Start Guide, but the 3D printing function was not working. Here is what happened:
1.The nozzle was heated normally and there was filament coming out from the nozzle. The temperature of the nozzle was normal on the Touch Screen.
2.The machine processed the leveling correctly and the heated bed can be heated too.
3.When I selected the file on the SD card and started printing, the machine was not working. On the Touch Screen, the temperature of the nozzle was reducing from 200° while it was NA for the heated bed.
4.Is there anything wrong with the sensor on the heated bed? Or is the heated bed cable damaged?
5.I attached 3 photos to illustrate the problem.
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During calibration I also saw that the print head touched and pushed onto the print bed, it then retracted to a safe distance so that the height adjustment ca start. I am not sure if this is a good way of programming calibration software, I think snap maker engineer should always leave a safe distance to the print bed, and always start from there, not copy over the height from previous calibrated point, if the previous point is lower than the next due to un even print bed we will have problem I just described.
May be something to consider for the Snapmaker team: install a touch or load sensor to the print head to avoid collision and or sending signal to the print bed and pick it up via print head (the same way cable finder tool of network installer operates). In this way, we can avoid damage to the printer.