Rescue print after Power outage
Hey, so around 40h into a 60h print job we had a power outage. I plan to resume printing but am unsure if my planned way is the best possible and would like to here a second or third opinion.
I plan to do it the following way:
1. Restore power
2. Heat nozzle and bed
3. Determine how much was printed by finding significant points of the object and counting the layers from there. Than having a look into the gcode opened with a slicer to see at which layer it stopped.
4. Home x y z by placing a thin sheet metal of .2mm onto the printed part and letting the BLTouch probe against it while z homing.
5. Opening the existing gcode with text editor and removing all the parts that were already printed as well as the bed mesh probing gcode G29.
6. Starting the modified gcode and again homing onto the existing print with +0.2mm offset because of the sheet metal.
Then subtracting these .2mm in liveZ adjust in mainsail.
Did I miss something or is there a better way to do it? How can I make sure there will be no Z Tilt routine performed?
Greetings,
Vince
6 Replies
I used to be able to do this in my old printer... homing X and Y above the existing print isn't a big deal, but I'd try to find an empty spot on the bed to home Z to know that my kinematic position was as perfect as I could get it.
From there it'd be a matter of removing all the gcode from the lower layers and re-starting the print -- HOWEVER, I did not have a START_PRINT routine like RatOS does, which means that the printer didn't try to do all the homing/tilt/mesh/etc stuff. You might be able to remove that from your gcode and manually get it to run from the mid point, I just have no idea if the printer will want to travel on an angle to the "start point" and may knock over the existing printed portion
Measuring the height where the print ended is pretty touchy though, as if you're too low you'll knock the print over and if you're too high the newly extruded plastic won't stick. Perhaps if you do find a position to properly home Z you could move the bed until you can see visually that you're at the correct height.
Note: I don't really recommend all this, but it could be your only chance to save all that time/work. GOOD LUCK!!
Thanks a lot, will try my best and let you know.
How can I change the homing position/coordinates?
quaint-moccasin•15mo ago
I just had to do this myself last weekend. This video in particular was of much help: https://www.youtube.com/watch?v=-wjE8eDiKWg
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HOW TO: Resume a failed 3D print!
It can be horribly frustrating if a 3D print that has already been going on for hours or even days fails and the printhead only moves in mid-air without printing anything. In this video, I’ll show you how you can easily resume one of these failed prints and save you a lot of time and money! Let’s find out more!
NOTE: This video covers the appro...
quaint-moccasin•15mo ago
Also this reddit thread helped too. It details how to get the shutdown logs about where your print head was when it failed. https://www.reddit.com/r/klippers/comments/qzxjrx/tip_for_resuming_failed_prints/
quaint-moccasin•15mo ago
I personally couldn't figure out how to modify where the print head moves to when trying to Z home, so I just used the "SET_CENTER_KINEMATIC" debug function to move the print head to an open section of the bed and manually Z0 it then just G92 Z0 for a manual Z home in order to be able to measure the layer height since I had power cycled and therefor didn't have the shutdown logs to go off of.
Hey,
Thanks for the reply. I actually watched this Video before I asked my question here.
I was able to change the position for safe z homing in the config file.
I also was able to find out on which layer it stopped by measuring the height of the model.
Sadly the object seemed to have moved about .5mm, maybe because I bumped into it while working in the printer. Therefore it's position was offset to where the printer thought the model is. I had to take it off the print plate and will print the remaining part, then gluing it together afterwards.
Greetings,
Vince