I've just got a Bambu H2D and am deciding how to store the filament (mostly PLA and PETG). I have access to a humidity controlled chamber which is set very low (single figures %), but the temperature is 55C.
Is there any issue with storing at this elevated temperature for long periods?
Thanks!
Filament Storage
Moderator: CrazyIvan
Re: Filament Storage
Welcome aboard.
Looking at the "glass transition temperature" (GTT) specification of the filament materials (roughly speaking, this is the temperature at which the plastic just begins to soften and therefore loose its ability to hold its shape), according to a quick web trawl, I get:
PLA 55 to 65ºC
PETG 75 to 85ºC
ABS 105ºC
However, we know we can't force PLA through a nozzle at 55ºC, so is this too high a storage temperature?
TPU -50 to -30ºC
We don't store TPU in a freezer, and we definitely can't print at room temperature! This low GTT gives TPU its flexibility (at normal temperatures).
So now look at the suggested temperatures for oven-drying filament (according to Bambu):
PLA 50ºC
PETG 60 to 70ºC
ABS 75 to 85ºC
TPU 65 to 75ºC
The question is, what would happen if temperatures went a bit higher? TPU doesn't suddenly become unusable because it was stored 50ºC higher than its GTT. The risk is the loss of dimensional stability in the filament diameter, which is the critical metric for FDM printing. Only be having a precise and constant diameter of filament does the printer meter the precise volume of material onto the print bed.
However, in storage, the filament can only become distorted if it is subject to forces such as tension or compression. This might be the case if filament were wound too tightly onto the spool, but if it were then it would risk becoming deformed during manufacturing/warehousing/transit.
IMO: go for it. You could start by testing a sample.
Looking at the "glass transition temperature" (GTT) specification of the filament materials (roughly speaking, this is the temperature at which the plastic just begins to soften and therefore loose its ability to hold its shape), according to a quick web trawl, I get:
PLA 55 to 65ºC
PETG 75 to 85ºC
ABS 105ºC
However, we know we can't force PLA through a nozzle at 55ºC, so is this too high a storage temperature?
TPU -50 to -30ºC
We don't store TPU in a freezer, and we definitely can't print at room temperature! This low GTT gives TPU its flexibility (at normal temperatures).
So now look at the suggested temperatures for oven-drying filament (according to Bambu):
PLA 50ºC
PETG 60 to 70ºC
ABS 75 to 85ºC
TPU 65 to 75ºC
The question is, what would happen if temperatures went a bit higher? TPU doesn't suddenly become unusable because it was stored 50ºC higher than its GTT. The risk is the loss of dimensional stability in the filament diameter, which is the critical metric for FDM printing. Only be having a precise and constant diameter of filament does the printer meter the precise volume of material onto the print bed.
However, in storage, the filament can only become distorted if it is subject to forces such as tension or compression. This might be the case if filament were wound too tightly onto the spool, but if it were then it would risk becoming deformed during manufacturing/warehousing/transit.
IMO: go for it. You could start by testing a sample.