I have had an issue which I am not sure how to start diagnosing it…
I am trying to print a number of 2 colour flat plates and have spaced them out over the bed. I am using PLA+ with a 0.2mm stainless nozzle on a smooth PEI print plate.
The first layer initially puts a black filament down (text on plate) and the second colour (yellow) is then printed. The finished product is yellow with black text on.
When it prints, the first black layer seems fine on both sides of the plate. But when it starts printing the yellow, on the right hand side it looks fine, but on the left it is almost as though the filament is not flowing properly and is missing… it looks like lots of random very small yellow spots. I have tried cold pulls on the head, ended up fitting a brand new 0.2 nozzle. I have even switched to a different roll of yellow PLA+ and the end result was the same.
The only thing I have had recently is that the hot end extruder keeps jamming and I have to strip it down to remove the clog as the printer is unable to retract the filament. I am trying to print something time critical, so have already ordered a new complete extruder so will have this ready in a few days.
Here are some photos of the results. I have blanked out some details on one plate which has client identifiable information for privacy.
I wondered if there is a way to print a test pattern to make sure the bed is properly level, or anything I can do to try and find the cause of this problem. If I print one plate at a time (3hrs approx) it works fine… it just seems to be when I try and fill the bed to save time is when it fails.
Just to make sure I understand this correctly: One side prints perfectly, but the other doesn’t?
Have you checked that the objects are positioned correctly in your slicer? I mean in Bambu Studio? If you copy them, the height of the objects might not be carried over and they might end up floating slightly.
Could you please post a screenshot of the first layer in the slicer? Of course, it could be something else, but just to rule that out.
By the way: Why is your printer plate so filthy? It looks absolutely terrible. What happened? Did you smear any glue or something on it? And I don’t mean the yellow dots, but the smudges underneath them. On top of that, there are an extremely large number of scratches.
I think you really need a new printer plate, and whatever you’ve smeared on it, stop doing that for PLA.
I’m not sure if this is down to filament not being fed, filament not staying put, or a bit of both.
You definitely have at least some adhesion issues, based on the tag that us barely even stuck down. Clean your plate with dish soap, a brush, and hot water. No isopropyl.
You would have a much easier time using a cool plate, it still gives a very smooth texture.
The plate actually isn’t dirty… These photos were my second attempted print and I used Bambu Glue stick, which I use on PETG, to see if it was an adhesion problem… I wash it with dish washing soap everytime I use it and it is completely fine when cleaned. I do actually have 2 new plates on order along with a new extruder and some new print heads.
It seems odd that the adhesion issue, if thats what it is, only happens on one side… if it was adhesion issues I would expect to see filament spooled all over the place… but there is no evidence of filament printing but not sticking. I wondered with the recent clogging in the extruder if it wasnt feeding properly and the filament was slipping and only ejecting a tiny amount?!
I have ordered another Bambu Smooth PEI Plate on this order, but will try a cool plate too when I next put an order in.
I have never heard of Arachne wall generator - just checked and it is set to classic… so next time I will change this too… is it better to use Arachne on every print? If so, I would have thought this should be the default setting
Despite its name, Glue Stick isn’t necessarily meant to provide better adhesion; it’s actually intended as a release layer. With PLA, this is absolutely the wrong way to use it. This may not be the root of the problem, but it certainly doesn’t help.
It’s not as simple as just applying a layer of glue when you encounter problems - it can actually make things worse if you don’t understand that it’s intended as a release layer.
With actions like that, you’re actually creating more problems for the troubleshooting process than you are by addressing the root cause.
Happy to help, hope we can get you sorted out asap!
Adhesion issues due to plate contamination are 100% not going to be consistent across the whole plate.
Arachne is just a different approach to how the slicer handles thin wall sections - it varies the nozzle flow to produce lines that are thicker or thinner than the nozzle opening itself. It isn’t “better” in all situations, it just happens to be better for this particular case, it will better handle the nooks and crannies between and around letters.
As I said, this was a test, to try and help adhesion. I always use glue stick with PETG after having a model stick so well that it destroyed a PEI plate when I removed it (on a Creality printer ages ago).
I am printing one of these plates individually and this is a camera shot of how the plate looks normally - as you can see… clean as a whistle. But frustrating that I seem to be able to print one at a time perfectly, but when I print a batch it fails… annoying as I have a run of 20 to print!
I do clean the plates meticulously every time I print, so I am confident there isnt any contaminants on the plate… well, as confident as I can be.
Arachne sounds great for these, as at the moment I am printing lots of these plates, which have lots of fine letters on them, so anything to improve detail will be great.
I tried printing them in gold with black letters, using PLA Silk, but the walls wround the letters made them look terrible… so I have to print the gold plate and then have the letters embossed above the top layer - which looks pretty good, but I wonder if Arachne would make the letters look better in this? I will have to try this when I get some time to tinker.
I don’t think you quite understand the direction I’m trying to guide you. Perhaps I should explain it differently: troubleshoot step by step and avoid introducing new sources of error into the process.
Clean print plate
Calibrate the printer
You may consider using a different filament
Clean the nozzle and, most importantly, tighten the screws on the tool head
Print one layer over the entire print bed and see if that works.
I think you’re making the same mistake that many of us have made before? Instead of starting the troubleshooting process at step 1, you’re jumping straight to step 99.
Why don’t you start there to figure out exactly where the problem lies? It could be something you haven’t even considered yet, like a faulty print plate heater?
Yes that makes sense… sometimes the pressure of trying to get something done means you jump ahead to try and speed the end result up.
I always clean the plate using fairy liquid (dish washing soap) and water… then dry with a lint free cloth.
I regularly clean the print head using the 100 degree cold pull process… which is weirdly satisfying
I have to switch between 0.4 and 0.2 heads regularly as I have two print runs I do regularly and I run the device calibration and the Flow Dynamics Calibration every time I swap hot ends. I must admit I know they dont recommend the automatic calibration with the 0.2 hot end, as it may not be accurate, but I have to admit I do use this for both 0.4 & 0.2 and havent had a problem previously.
As I switch hot ends regularly, I do frequently check the screws are tight and do replace with new ones.
I havent printed a single layer over the whole bed, so will try this tomorrow night when I get in from work, as I wont have time tonight as just going to bed as I start at 5am, and let you know the outcome… thanks
I hadn’t considered a faulty print plate heater… is there any way of proving this? I do have an infra red thermometer, so could heat the bed and take readings at multiple spots to see if its consistent?
So, if this is the same on every print it looks like the AUX fan is running at 70%… obviously this print is different, so I dont know what it was set to on the failing prints… but will check when I try a batch again - any recommendations on what and whether to change this?
For example, print one layer over the entire plate - like on the photo i posted. This should also highlight any other issues. If that doesn’t work, you’ve got a much bigger problem.
I know you’re short on time, but I think the list I’ve described will take no more than 30 minutes. It’s better to take it step by step now, and then tackle the problem head on, than waste time trying every possible solution.
If your printer isn’t printing the first layer cleanly, then you don’t need to worry about your project, because that means you have a fundamental problem.
You don’t have to use this, but something along those lines - not to clean the print bed, which is nonsense anyway - that’s done with soap, but just to check if your printer has a fundamental problem. As I said, it might take about 30 minutes, but it’s time well spent.
I think you are getting heat creep from such a glacially slow and massive first layer on a tiny 0.2mm nozzle. Slice that plate, select the flow visualizer in the preview, and look at the first layer. Under 1mm/s flow, and over 15 minutes? — You need to strongly address cooling up in the gantry area, use a vented riser first and foremost to let the heat leave, and if you continue having problems try with door open as well. IMO your mentioned clogs that follow this problem are because of the filament softening early because its sitting in a sauna for many many minutes, not traveling thru it like it would be during normal speed printing.
I think I understand what you’re saying, but not 100% sure about how to fix it… this is what I see when I slice the model and then select flow visualiser…
Which seems to show a flow rate of 0.03mm/s for most of layer 1 - which seems to support what you say. Also as the heat will build up at a similar rate every time I print, it would seem to support why it starts to fail at a similar point each time… As its PLA, and not another filament with nasty fumes, perhaps I should raise the lid to allow heat to escape from the top of the printer?!? Once I have done the checks and test print suggested by @RetroSharky I will try your suggestion too. It will be once I get back from work tonight - thanks
One other (I suspect unrelated) problem I have encountered on the last couple of single plates I have printed is that there seems to be scarring on the topmost layer. This has only just started as previously I have printed dozens of these and the top layer has always been perfect. I am printing a test batch of 3, while I am at work and cant do the test print, and have turned ironing off and I suspect that this will leave a cleaner finish.
In order to get a nice clean top layer, I have been using rectilinear ironing on the topmost surface - which has always looked great. However the last couple of singles have been finished with a very poor top layer, looking as though the head has been dragging, or something like that. Here is an image of the top layer on a single which I printed last night!
Just out of curiosity, in the preview are you able to drag the “layer slider” along and see what order that first layer is put down in. As others are pointing out, it might be the case that the failing sections are more “early” or “late” in the layer rather than “left” or “right” of the build plate. It would be interesting to see regardless.
By “layer slider” I mean the horizontal slider at the bottom of the preview screen rather than the vertical “level” slider on the righthand side.
