Hello, i have another Problem with my surface on the left corner.
I am currently printing this chess board an the left corner surface looks a bit strange…
Filament is dry, has anyone a suggestion what I could do here?
Two possibilities come to mind:
- Local bed adhesion causing slight warping which in turn leads to overextrusion type defects due to the lower than specified effective layer height. => Thoroughly clean the bed again, maybe try to use brim ears and consider increasing temps by 5° (bed & nozzle) for the first layer only.
- A draft causing local thermal management issues. => Keep the chamber temp in the sweet spot at 35° (but beware of heat creep if/when ironing), tape off the front left door gap (if it is this corner! For the poop chute corner, you may want to rig a deflector keeping the chamber air in but being open at the bottom), lower chamber fan.
There may be other, more complex root causes. But these are probably the easiest and most common to address first.
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Thanks for your reply, i looked at the chess plate yesterday in the evening and the problem is caused definetly by warping because the right corner on the backside of the printer (right side when you stand in front of the printer) is lifted up.
But i really don´t get why my PLA is warping inside a closed chamber? I tried a second print and had 5°C more on the bed for the first layer but that also did not work. The door of my P1S was also closed.
I also tried to turn off the AUX Fan.
Over night I printed the chess board again but with the black and white tiles turned towards the build plate because only that way, the surface you play chess on looks good. The top surface of the print is again not good…
Also to mention I use the BIQU Cryo Grip Pro Frostbite Textured Plate with 35°C (first layer 40°C). My PLA is dry.
Thanks for the help!
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I know you say the PLA is dry but you give no details. Unfortunately many think their filament is dry when it’s not. Maybe yours is dry but the issue looks familiar.
Here is a part I was printing when trying to get my water issues under control. With wet filament I was seeing lifting in the back left corner which led to rough top surfaces. That defect went away after effective drying of the filament spool.
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Thanks for your reply. I have two ESUN Filament Dryer and as recommended in the guidebook I dry my filament rolls for 4-8 hours (mostly over night) on Setting 1 for PLA and PLA+ which is about 40°C. Worked fine for me. Humidity inside my AMS is about 10%.
Do you have any other suggestions or tips for drying the filament? The Build Plate was cleaned before the print with warm water and soap only and dried before usage.
I had something similar a few weeks ago with another self designed part for a birthday present. There I had a Text printed in black PLA on top of a part which was printed in Silk Silver PLA. The text turned out pretty bad until I changed the settings in the wall generator a bit. Filament was also dry on the first print which was a fail.
Thanks again!
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Drying filament is confusing and things are worse thanks to sensors that may or may not be accurate.
Drying to 10%, if your sensor is accurate, should be good. I dry my filament to a 19% reading in a modified Sunlu S2+ so if both of our meters are accurate, your filament should be more dry than mine. There can be a number of reasons why one or both meters could be inaccurate but they should be repeatable.
If the 10% is accurate it probably isn’t moisture. Do you know what the ambient humidity is where you have your dryer? If you open it up for a while before turning it on, you should get a cool reading which should agree with your ambient humidity. Once it starts heating though, the reading will be artificially low since relative humidity depends on temperature.
If you were drying for just 4 hours, there could be an artificially low reading just because it takes a while for the water deep in the spool to get out. But drying overnight should give time for the water to get out.
There are other ways it could still be water but I don’t know how likely they are.
There is a test that you can do that can give an independent “measure” of water in the filament if you have a good battery-powered hygrometer that can read down to 10% or lower. Get a gallon ziplock bag and put the spool and hygrometer in one and seal it. Monitor the humidity reading and when it stops changing the reading is representative of filament moisture.
There isn’t much data available but when I do this test my filament bottoms out my hygrometers at 10%. The actual value is somewhere below that but that’s good enough to get good prints for me. If your 10% value in the dryer is good, your spool should pull a hygrometer in a bag to 10% or below too. That would be a confirmation your filament is at least dryer than mine and my PLA prints are all like the dry image above.
There’s more to all this if you end up doing a deep dive but your issue might be something else. One other thing to consider is people have noted “microclimate” kinds of effects where things happen near the door, or the back, or a fan, or are somehow location-dependent in the printer.
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I do not have @MZip deeper insights into moisture uptake but I did notice your relatively low drying temp which can affect drying times significantly. In my case, I also do overnight drying, but at 55°C for PLA.
While I did find Bambu’s drying recommendations a bit conservative (i.e. longer than usually needed), that is actually a good thing when we do not neccessarily have an idea about actual filament moisture content.
https://wiki.bambulab.com/en/filament-acc/filament/dry-filament
A tried method to estimate when drying has been successful is of course to measure the roll weight down to 1/10th of a gram intermittedly, plot the delta and dry until moisture loss is approaching 0. Personally, I do not go to that much trouble though.
Regarding build plate cleaning, I also use water and dishwashing liquid but add a clean stiff brush (dishwashing brush, fingernail brush) and some muscle grease to the mix for the textured plate.
Regarding warping, build plate adhesion and draft prevention are needed but do not directly address the root causes. For PLA, I have found 35°-39°C chamber temp to be a bit of a sweet spot (but only up to a max of 35°C when ironing!!!). There are hygrometer holders on MakerWorld to get that info with a P1.
Further methods to even out the layered cooling unforrunately slow the print. They.work by reducing the heat input per volume material to reduce heat differentials. Being volumetric, reduced layer heights and/or slower printing are quite effective.
As for text, the Arachne wall generator is a bit of not so secret weapon for me 
For good, flush text, I also change the text object type to a modifier for best results.
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Somehow I totally missed the 40C drying temp. Good eye! Drying at lower temperature will result in higher moisture content at any given relative humidity indication than would be hit at higher temperature.
That may be why the low humidity with still lifting and such.
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Thanks again for your reply and the help.
Yes, the printer, the filament and my dryer is in the basement of the house. In winter I only have about 15°C max down there with a lower humidity but right now I have around 40% more or less. Reading from my small amazon battery humidity and temperatur sensor.
Thanks I will give that a try the next days.
I printed the Box for my chess Board last night with another filament roll and increased the temperatur of the bed to 45°C and used a brim. The print took almost the whole build plate.
Travel Chess Set by JamesThePrinterMakerWorld: Download Free 3D Models
This is the model I printed, scaled up to 170% because I wanted it to be a bit bigger.
As I said on the first look this morning, the box looked fine but I have to give it a detailed look after work in the evening.
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Ok thanks, I can try to use setting 2 of my dryer which is for PETG but there should be a temperatur of about 50°C. Maybe that works, I will give it a try.
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10% relative air humidity sounds extremely low to me. You’re unlikely to find such low humidity levels naturally in most everyday environments. Areas like the Sahara Desert or the Atacama Desert are known for their extremely low humidity levels, sometimes dropping to 10%.
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Thanks for your reply, yes I know but that could be because of my humidity sensor which i got from amazon a few years ago, maybe those readings are not exactly correct. I store one in the AMS unit with Silica Gel.
There are some cheap humidity sensors that are factory calibrated and are actually pretty accurate at least when new. The ones I’ve been using all agree well with each other (JEDEW ASIN: B07GR67G1M, Amazon) but respond slower and slower at low humidities. I think certain chemicals may also poison the sensor (saw something about that somewhere but don’t remember where). They are cheap, though. Might be worth getting some new ones to at least compare?
@user_276529758 - there’s two parts to the humidity measurement - relative humidity and the temperature when the measurement was taken. OP was running his dryer relatively cool (40C) so not as much water would be removed. 10% sounds great when PLA filament is dried at 55C but won’t be near so good when drying at 40C. Don’t know by how much but it will have more water left in it since it takes heat to free up the water.
There’s not good data that I’ve been able to find for PLA moisture contents especially dried at different temperatures so hard to make quantitative comparisons but qualitatively, dry at cooler temps and filament won’t get as dry.
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I have another Question: Inside the Bambulab App for IOS you can go to “Devices” and under “Filament” you can see your AMS Unit with the loaded filament. I think this is new in the newest Update but you can see the humidity in % of the AMS now. Mine shows 30% right now with two other spools loaded inside at the moment. Is this measurement in % accurate?
I don’t know that answer, unfortunately. On PC the humidity is only reported with a single digit. (At least on my system which hasn’t updated firmware or Stufio for a couple of months.) On iOS do you ever see two significant figures like 31% or 25%? If it only hits the 10’s (10, 20, 30%) then some precision is missing and depending on how they round, the “error” could be up to 10 percentage points but more likely within 5 or so? If we knew the part we could refer to the manufacturer data sheet for the actual accuracy of the hygrometer itself.
But in general the AMS humidity reporting seems in the ballpark with my AMS units. As an aside, and possibly another part of the puzzle is my AMS units are both showing 10% (a “1” indication). 30% (“3”) is high for me and I swap the desiccant in the AMS when freshly-dried spools of filament going in don’t pull the AMS humidity back to 1 from a 2.
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I took a look at it yesterday in the evening, on Bambu Studio on PC and also on the IOS App it shows also 28% so it shows 1 percentage points.
Humidity reported by the hygrometer or AMS sensor does not neccessary tell the correct water level in your filament. It is the water level in the air inside AMS.
Just saying.
Eventually, filament will give away water to much “thirsty” air so that it’ll reach equilibrium, but for how long, days, weeks, month?
As far as I know, there is no direct method to measure water level inside filament
I did some experiment with 3kg PA6 spools + about hundred gram of dry silica beads + hygrometer inside a sealed container. I wrote down the %RH level of air inside every hour after filling with fresh dry silica beads. This is the result after about 4-5 months.
Please notice, all 3 spools had gone through oven at 80°C for 16 hours before putting inside of this storage. Same for silica gel beads.
This is humidity level of the same room after raining all day (today)
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Yeah, so I was having problems with adheasion left front of bed today. I may have fixed it by increasing bed temp and slowing first layer. But when I touched the bed I was finding the spot that was a problem seemed not as hot as the centre of the bed. I’m in a print at the moment, with the bed temp and speed changes, I’ll get out my IR temp sensor to investigate further.
Have you washed the bed with dish soap and hot water? Gave it a really good scrub? A contaminated bed is the most probably cause of adhesion issues.