I’ve had the A1 a week or so and am having several issues, though for my first post I’ll start simple, as I am starting to think the whole ‘out of the box’ thing is a little bit exaggerated and that this printer will require tweaking and knowing what each setting does before really being able to print whatever I like (after about 6 prints I think I’ve now researched most of the settings to try to overcome various print failures, ‘wiping’ being something that was first to go as it knocks all of my prints from the bed).
When a print completes it lifts the extruder high on the Z axis and out of the way before moving the bed forwards so you can get the print off the bed. Now when I send another thing to print, the extruder is lifted up on the z axis to the top and then even more as I hear a clicking sound for about a second, before it realises it’s at the top of the travel. Is this normal, or is it breaking something?
It’s kind of similar, but in that vid the clicks are spaced apart further, my noise the clicks are much closer together (maybe double time), and it happens once the z axis hits the top of travel.
The extruder only seems to go right to the top of Z axis when my previous print has been relatively tall (the things I’ve printed were 17cm). I’ve not noticed this when I’ve tried to print gears 0.5cm high gears (instead the issue is the nozzle seems to get stuck in the bore, then push the gear all over the plate while filling the bore with a puddle of filament)
I have the same problem with my A1 mini. If it is a medium tall print (does not have to be very tall), it will go so high after printing that the next time it starts a print, it will go more than all the way up, and it is making a terrible noise, that cannot be right. Even if I press home when it is high up, it will go a little up before it goes down, and you cannot override it, because you have to home it before you manually ride it. Is there no end stop on top? Or can it be adjusted? Have anyone found an answer? Can it be fixed in the gcode?
sadly that seems normal if you finished a print and it is way up top, especially starting another after the stepper motors are disabled at the end of the last print. Luckily it can be fixed in both the start and end gcode section of the printer.
Now proceed with the utmost caution and at your own risk.
The below section is the first in the start G code that has G91; relative movement and a Z40 which means move up 40mm nice and slow at 1200mm/s followed by Z down by 15mm. What you can do is if you are sending second print immediately after a tall print has completed, you can try commenting that section out with a semicolon or just change the Z movement to a 4mm instead of a 40, then save it as something like “Use for secondary tall prints” or something. Try that and see.
;=====avoid end stop =================
G91
G380 S2 Z40 F1200
G380 S2 Z-15 F1200
G90
Now for the end gcode so that it does not run all the way to the top after every print, you can look for
{if (max_layer_z + 100.0) < 256}
G1 Z{max_layer_z + 100.0} F600
G1 Z{max_layer_z +98.0}
{else}
G1 Z256 F600
G1 Z256
{endif}
and change it to something similar to
{if (max_layer_z + 100.0) < 256}
G1 Z{max_layer_z + 10} F600
{else}
G1 Z20 F600
{endif}
I’ve seen this behavior and have been meaning to ask about it. when a tall print, say around 200mm… it goes up after the print, and seems to ignore the how high it can actually go? Like there is no upper limit switch and the Z-Axis tries to go too far.
Even shorter prints, it goes up a long way to clear the print, too far… My work around for this has been to when its near the top, I go to Controls XYZ, and move the Z-Axis manually back down. the problem here is that it goes down a few mm and tosses up a dialog to cancel and go Home.
I think it should let me continue to lower it, till I am ready to hit home on the control panel, not the dialog it tosses up… If you hit Home before you’ve lowered it enough, it will go back up to far and make more noise. Once I’ve lowered it to about mid level, you can hit Home and its fine…
Perhaps that G-Code setting is the way to go, but you’d think it would know what level or how high the z-axis is at and not exceed that and hit the top… Might be worth a ticket, though at the moment with the bed cable issue its hard to know how that will play out…
The video above to me, the printer is way to close to the wall, specially considering the seeming weakness in the heat bed cable that Bambu is working to resolve…
I’ll have to try that… I just thought it was odd that it just won’t let you move it where you want… Glad you have most of the answers to my questions… thanks
Oh, that was easy! I automatically released my finger when the message appeared, and after releasing, you cannot press again, but indeed, if you just keep holding, it works! I also checked, and via Bambu Handy and Bambu Studio, you get a message if you try to move before homing, but you can just close it and continue. I think I’ll go with these solutions, and let the G-Code be for now.
Is anyone experiencing this with the A1 Mini? I am printing objects about 75mm tall and it hits the top of the Z axis twice before homing when starting the following print.
I tried to submit a ticket to Bambu but guessing they’re swamped. It just seems like it should be a very common issue and hitting the top of the Z makes a loud noise with the motor trying to push past it.
Manually moving the Z down & homing after every print is a bit annoying when I’m trying to keep this printer busy ~18 hrs/day.
The start code for the mini looks similar to what was shown above for the A1, just scaled down a bit.
;===== reset machine status =================
M290 X39 Y39 Z8
The Z30 is definitely causing 1 collision and I think the Z8 is the 2nd, although I’m not as sure.
-Is the purpose of moving Z30 then Z-20 to lift it off the bed in case the nozzle is sitting on the bed when starting?
-Could a smaller Z movement like Z5 be sufficient? There is a small gap at the top of the Z rail when starting, but Z30 is too much.
I can post a video if needed, just trying to avoid as many collisions as possible.
Not sure if it’s related but had this happen a few times (also on follow up prints) after I removed the timelapse gcode from the profile (did that following a tip from the forum so I would I have a clearer view on my travel movements in the gcode preview).
Restoring the original profile fixed it.
This happened to me a couple of times yesterday, repeatable scenario. I printed a 60mm tall container, the printer does its thing with raising the head and presenting the print. I go to print something else and it raises the head to the top of the z axis until it grinds for a half a second then comes back down. Watching with interest.
Hmm I searched about this in the forum and it seems that may be the X axis (print head) hitting, not the Z (cantilever arm)? I haven’t really used the timelapse before, but I may have checked it on once as a “first print” thing.
@JohnBCS glad to know I’m not the only one. I think I know what to change but I’m trying to give the stock code a chance since I’ve only had this machine for a few weeks. I’m sure someone out there knows…
I’ll test mine again in a bit. When I hear the grinding, I don’t remember the print head moving, but I wasn’t really watching for it either, so I’ll do the setup again and check that.
I just find it hard to believe that machine crashes caused by G code can be considered normal.
I understand the axis are using some form of low current collisions to home the machine, but this start print movement occurs before the current is turned down.
Starting G code:
;=====avoid end stop =================
G91
G380 S2 Z30 F1200 First collision
G380 S2 Z-20 F1200
G1 Z5 F1200
G90
I got a response from Bambu pretty much saying they know it’s an issue and I need to manually drop the Z after every tall print until a future firmware update. I think it should be an easy fix, I’m just not sure why they have the start & end code the way it currently is.
I’ll wait and see if anyone else has a solution then maybe try to edit it next week if not.