I recently noticed that when my AMS reloads a spool, especially in low quantities, the info it provides is wrong. How does the system decide how full a spool is? Is it by measuring how much traction needs to be applied on the filament to roll it? If that’s the reason, I could point my spooler weights as the culprit…
Also, the humidity level always seems to be at 1 while I did have to redry some filament recently. On prior versions of the firmware/software combo, I did get a gradual moisture rise indication, but lately I don’t.
As far as I can tell, used filament is an approximation based on memory and used length.
As for humidity, a hygrometer measures air moisture. That can be completely unrelated to moisture in the filament. Therefore, I tend to dry all filament before putting it in the AMS or bagging it with dessiccant. That is the only way for me to know how much moisture is in a roll (i.e. close to 0).
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Are you using Bambu filament? If not it will not be able to tell you how much is left, because it has to use the RF id.
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Eno: do dry my filaments, even redry them if called for. I also have desiccant boxes inside the AMS and check them for color change on a regular basis. Even so, if by chance I had to open the AMS and work on something in there, then close it, if it dragged on to much the indicator in Bambu Studio would always reflect a temporary rise in moisture inside the AMS. Lately, it doesn’t budge anymore at all.
Silver: Yep, Bambu filament. I tried something just a moment ago, though, and removed the spool weight, then reloaded the spool in the feeder. Then it showed proper info, so I would assume that the system factors how many times the rfid passes the sensor in a given time as the filament is feed/rewound to calculate a weight estimate… bummer really, for these weights reall stop the spools from jumping when they’re getting to their end. I might need another solution.
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The AMS hygrometer response to opening is very much dependant on the environmental conditions. If you have a dry spell, you’ll not see much of an effect.
For me, the cheap round hygrometer in my AMS is more useful than the more sensitive AMS sensor. Displaying a munimum of 10%, I know that my dessiccant needs rejuvenation when it can not keep the min moisture anymore. So once it reads 11%, I know I should give it a ride in the microwave.
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Edit: Since you are in the same time zone, we did have a long, dry spell in Germany. My printer room was below 10% humidity for days.
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It uses the RFID tag’s revolution past the sensor and length drawn to estimate the circumference and hence a ‘very’ rough estimate of the weight, assuming things like tidy winding, etc. If I’m down to the last 50g, it’s probably more worthwhile to unspool it and hang it off the rear holder than to rely on the AMS estimate. With it lose, I can scale weigh it regularly.
I do have a cheap round hygrometer in the AMS too. With freshly dried desiccant pellets, it never drops below the 20 mark. I guess not all these things are giving the same readings from one unit to another.
As for the weight estimate… well, it’s all over the place anyway. I guess the good old scales are the only sure way, at this juncture.