Select one model to print but prints a different one
There have been several times over the past several months when I very specifically select a model to print but when I check a few minutes later, after it's actually started to print, I find that it's printing a different model. My SD card has a lot of different G-Code files. I use the PRUSA display and the button/dial to select the one I want to print and then click that button. Usually it prints the one selected, but every once in a while it ends up doing a different one.
It seems that sometimes the one that gets printed is the one in the displayed list that's immediately AFTER the one that I had selected, indicating to me that MAYBE when I clicked the button it actually did a quick scroll-down-to-the-next-model AND a click, so that I didn't actually see that it had almost instantaneously moved to the next model before recognizing the click.
But other times the model that gets printed is NOT the immediately next one, but instead one that is somewhere else in the list.
Is anyone else ever seeing this happen? Any idea WHY it happens?
RE: Select one model to print but prints a different one
I have absolutely experienced this too. It's because the screen is sometimes slow to update which item is selected, especially when there are lots of files on the sd card.
My process to prevent myself from printing the wrong one is: move the wheel until I've selected the one I want and the text starts scrolling. Next, move upwards or downwards one item, and let its name start to scroll. Then carefully move the wheel in the opposite direction exactly one menu item - the detents in the selector wheel don't seem to match 1:1 for menu item selection unfortunately - and make sure that the item's name starts scrolling.
RE: Select one model to print but prints a different one
This is driving me crazy! It's super frustrating and you can't see that the wrong file is selected until it actually starts to print. Waste of time and filament. Could end up with clogged nozzle due to temp/filament mismatch someday (not happened yet). My guess is that the rotary encoder in my MK3S is sub standard quality. When doing the selection (press down) it sometimes (often) actually rotate one notch forward and then selects.
RE: Select one model to print but prints a different one
Adding to this - i have a relatively new i3mk3s that i built this summer (june/july 2020). More or less worked great after assembly, some stringiness with various PLAs (even prusa provided) which were "resolved" by taking my temps down and z lift to 0 for any print.
With the prusa i3mk3s not printing what file was selected from SD card.. I thought i was just goofing it up as some described, slightly scrolling and clicking and unfortunately you dont see the file name until the print has actually started. But this just happened to me 3 times in a row; I was very careful in selecting, even waiting for the whole file name to scroll as some mention. STILL it prints a totally different file.. sometimes its the one right after, others it has been just a random one in my list.
The only way i got this to stop was to either delete everything else or put every other file into a folder as well, you'll know if it clicked on a folder.. and surprise it hasn't done it once... so my 2cents is this IS a glitch.
RE: Select one model to print but prints a different one
This is a persistent issue with Marlin firmware, not just Prusa's version. Various delays and debouncing methods have been tried, but it's difficult to keep everyone happy. What I learned on my Mk3 was to scroll to the file I want to print, then wait 2-3 seconds before selecting to print.
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He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan
RE: Select one model to print but prints a different one
This is a persistent issue with Marlin firmware, not just Prusa's version. Various delays and debouncing methods have been tried, but it's difficult to keep everyone happy. What I learned on my Mk3 was to scroll to the file I want to print, then wait 2-3 seconds before selecting to print.
.....or run Octoprint 😉
RE: Select one model to print but prints a different one
Why not create folders on the SD card and move the files into appropriately named folders. I have a lot of folders, usually named after the project, so it is easier to find the file I'm looking because there are a lot fewer files to look through. I rarely make a selection mistake anymore since the code is much faster when scrolling through the files.
jwv
RE: Select one model to print but prints a different one
It drives me crazy. I can have right file selected, name scrolling and it switches to other file at the exact moment I press the knob (I'm trying my best and I'm sure I didn't turn it). Either detends do not correspond encoder trigger lines or software updates display after pressing knob to show the "real" selected file.
My solution for this is to have 1 file in root directory of my sd card. This way I eigher select directory by mistake (which is not an issue). Or I start to print the only file that was in root directory (what I wanted).
I'm really thinking about modifying a firmware to do something about it. Like for example, ignore any file "scroll/switch" if the knob is pressed straight after it. Or somethign similar. I'll have to experiment.
RE: Select one model to print but prints a different one
This is a persistent issue with Marlin firmware, not just Prusa's version. Various delays and debouncing methods have been tried, but it's difficult to keep everyone happy. What I learned on my Mk3 was to scroll to the file I want to print, then wait 2-3 seconds before selecting to print.
.....or run Octoprint 😉
Or run Pronterface?
When printing from the card my habbit is to wait few seconds for scroll to stabilize and then click to print.
RE: Select one model to print but prints a different one
I think this behaviour is slightly better after latest firmware update. Or I'm able to be super careful... or I have less files on SD root atm... or something.
RE: Select one model to print but prints a different one
Octoprint and Prontoface is not always an option. I noticed that USB on those 8bit boards just can't handle the speed of commands on some models. Lots of gyroid infill or curves on faster print creates an issues. You can search internet and find few videos explaining it.