I’ve printed a lot of BL matte PLA colors without this particular issue. Typically, layer time won’t affect color this much if speed, temperature, layer width and height are constant throughout the discolored area.
Ash Gray, white, dark chocolate and black of the same print doesn’t have this issue. It’s the first time I used Nardo Gray, I’m wondering if it’s this particular color or I got a bad batch. Could someone please confirm this? thanks
Can you mark up the real life photo to show which corresponds to the red region below?
What happens if you run the helio analysis on it?
There are internal geometry behind the bottom discolored flat area, which is why layer time is different there, but other BL matte PLA colors don’t have the same issue.
I can’t use helio analysis due to confidential / privacy matter.
Moisture in the filament can cause banding issues like this. How are you drying your filament?
I normally don’t dry matte PLA as they go straight into hermetically sealed containers like AMS or cereal containers. I’ll try drying it and see if it makes a different in this case.
Interestingly the prime tower doesn’t have the issue, just the color is darker with dense layer height.
I’ll order some nardo gray today, I’d like to try to replace this, I was looking at thermochromic additives to replicate this sort of measurement.
Is there any chance what you are seeing is just variations in translucency?
So you’re assuming it’s dry from the packaging? This seems to be a common misconception. Filament isn’t “dried” between manufacturing and packaging.
Thanks for helping out, please only order it if you can use it for your projects. I’m just wondering if the issue is with Nardo Gray only. Google search result shows a few mentions about similar issue with Nardo Gray. Maybe it’s more hygroscopic than other colors. I’ll try it again after drying it.
I don’t think it’s variation in translucency. It printed with 0.4mm nozzle, 2 walls and 5mm of infill before the internal geometry changes.
The last time I stocked up on filament, on a whim, I ordered a spool of Nardo Gray. Even though I am well versed in color theory, I had never heard of Nardo Gray. When I looked it up on-line I found out that the color is rather new, having been developed by Audi a little over a decade ago. Named after a test track whose pavement is the same color. Polls show that it is one of the least attractive colors for cars, although, since becoming aware of the color Nardo Gray, I have seen dozens of cars from various manufacturers that are Nardo Gray.
It seems to me that the armchair quarterback go-to explanation of why prints go bad is that the filament hasn’t been sufficiently dried. Yet, I live in a rain forest, never dry my filament, and have never had a problem with wet filament. Although I do keep open filament spools either in an AMS unit or in a dry box with desiccant packets. I will even go so far as to offer the opinion that repeated active drying degrades the filament. At times I get the idea that filament drying tends to be more psychological than useful. Kind of like cleaning one’s build plates with IPA and sandpaper.
Although I haven’t had any problems with the Nardo Gray that I have, I have seen similar banding on prints. In every case the banding has coincided with either the internal structure or another object being printed next to it. It is more likely to occur on those prints where one object or part of an object is considerably taller than its companions. Recently I had banding on a part printed in White but not when the same part was printed in Sakura Pink. It may just be that some colors are more translucent than others which is obvious when I shine a light through the White as compared to the Sakura Pink.
Drying improves the banding quite a bit, but does not eliminate the banding completely. It also makes it slight darker too.
I think there are multiple factors in this case: filament, printer (U1) and maybe slicer (Orca)
Nardo Gray maybe more sensitive than other colors. I’ll dry it for another 8 hours and see how it goes.
It’s a hexagonal shape with hexagonal symmetry internally, so each side should prints the same. But it didn’t, the banding is most prominent on the side where layer starts and it gets less prominent with each following side. The banding is pretty much not noticeable on the 6th side where layer ends.
It’s either the U1 is off or slicer bug, but it only occurs on this Nardo Gray. Other colors printed fine without this issue. So, I don’t know. I’ll skip using Nardo Gray for now.
I can’t test this on my bambu P1 series printers as it’s a multi-material setup (PLA with PETG support)
BTW, the prime tower came out clean with no issue 
The culprit is likely a combination of Orca slicer, wet filament and variable layer height. Just finished one without applying variable layer height, everything looks great. Drying PLA for 16 hours is nuts!
Respectfully disagree. My old printer didn’t print fast and didn’t exhibit the kinds of water effects that my X1C does. The water effects caught me off guard - I wasn’t anticipating them and it took a bit of effort to sort what was going on and determine the cause - water. It was a total surprise to me and not a product of overactive imagination.
I then looked into drying, weighing, timing drys and measuring humidity. Once I got drying properly sorted, the various issues I had been seeing - lifting, stringing, doughy surfaces, top surface scarring - all went away. And it was repeatable. I had a time crunch and used filament that didn’t get a good dry and the effects were back.
If you keep your filament in dry boxes with desiccant, and if that desiccant is kept “dry”, you are drying your filament in storage. It is inefficient, incomplete, and slow, but it’s just physics. By keeping your filament in controlled environments, the rain forest part doesn’t actually matter. Filament that gets exposed to humid air does pick up water but it is also a slowish process and a few minutes here and there doesn’t really matter.
The thing is people can anecdote this to death and frequently do. We don’t know the starting moisture content of the filament you use. If you are lucky enough the supply chain to you may not have the same age or filament exposures to humidity and you may just be starting with drier filament than many others.
To really nail this down instead of hand waving, we need moisture content measurements - which are easy to do. Just measure the humidity in a sealed container with the filament. It isn’t a direct moisture content measurement but is proportional to moisture content. The container needs to be just barely bigger than the spool and the spool should have lots of filament still on it so the spool moisture dominates, but that number can be used to compare what people are actually printing with versus what they think they are printing with.
I would guess your filament is dryer than you may think thanks to your handling and dryboxes/AMS. For my setup here, the way I dry and store, all of my prints now are with filament that pulls hygrometers below 10% RH and I don’t see water effects. Everything fits. I control the water content, know how to test water content, and have my own “no-go” water limits.
It’s not “armchair” and it is absolutely useful. I still have all the handwritten data I took while troubleshooting why my prints were getting worse, and worse, and worse.
I would be very curious what you see with your filament. Humidity/moisture levels when you open fresh spools and what you are printing with. Since you aren’t seeing the effects, I would guess your numbers will all be good enough.
Calling moisture effects other peoples’ imaginations isn’t helpful. Water effects are very real and I wasn’t even aware that water could cause what I was seeing until I started trying to figure out what went wrong. It wasn’t my imagination. My water effects come back if I use inadequately dried filament. It’s reproducible and I have photos I took when sorting it all out.
And it’s pretty hard to discount the photos people post if you’ve seen similar with your own machine. Do you think people are faking the images? What do you think causes the problems people post about?
When people hand wave there’s lots of opportunities to get things wrong. What settles it is data/numbers. Humidity measurements of spools does give you a number proportional to moisture content. Period. It’s a physical fact that a whole industry is built on. Anyone in doubt should read up how the archive industry uses desiccants - to humidify or to dry - and they measure moisture content by humidity. They condition silica gel with humidity and they sell desiccants at specific humidities in 5% increments stock and 1% increments special order at least where I looked.
I’m pretty sure that those who don’t have moisture issues have some combination of supply chain and their own drying/storage procedures that gets them low moisture filament. It’s not that everyone else is “imagining” water effects and those who have seen them and spot them in other peoples’ prints aren’t “armchair quarterbacks”.
We have a handle on filament moisture and could settle all this stuff pretty easily if people took the time to actually try it. Those without issues likely have dry filament. Those with what looks like water issues likely are running with wet filament.
Hello, I stumbled across this while researching the same exact issue with Nardo Gray! This is the only BL filament I have this problem with also. As suggested, I dried the filament and all my problems completely went away.
Looks like a variable layer height issue.
I’ve printed many roles of BL Nardo Gray and have no issues. It’s actually one of my favorite every day use filaments.
