The printer does not ‘recognize’ filament. The AMS simply ‘recognizes’ the RFID in the spool.if you buy a refill from Bambu it comes with a RFID tag and a new spool label. If you are refilling an existing Bambu spool with a filament different from the original you must change the RFID tag or it will be recognized incorrectly and you should change the label to refer to the new filament…
Then what is PETG-HF? From what I read should It really be called PCTG-HF?
I don’t know what you read about PETG-HF or why what you read makes you think that it might be categorized incorrectly.
I’m not aware of any industry standard for what HF means. Something is being done to increase the melt flow index of the material, ideally without harming the physical properties much. Could be a different process for solid-state polymerization that might result in lower molecular weight or reduced crystallinity. Could be a chemical difference with a third co-monomer glycol or even some amount of acid substitution. Could be alloying the material with some amount of another polymer. If Bambu Lab thinks they have a competitive advantage, they might not be very forthcoming with exactly how the high flow is being achieved.
My understanding is PETG-HF is formulated by adjusting the base PETG polymer composition to have a lower viscosity allowing for a higher flow rate during 3D printing by enabling faster printing speeds with less resistance through the nozzle while still maintaining the material’s key properties like strength and flexibility; this is typically achieved by modifying the glycol content or adding specific additives (cyclohexane dimethanol) that enhance fluidity.
Here’s what I have been reading;
Cyclohexane dimethanol (CHDM) is added to polyethylene terephthalate glycol (PETG) to improve its properties for 3D printing and other applications:
- Crystallization: CHDM prevents crystallization by replacing ethylene glycol in the molecular chain. This is because the larger CHDM monomer creates a block of longer atoms that don’t fit together like ethylene glycol does.
- Melting point: The new structure of PETG with CHDM lowers its melting point.
- Heat resistance: PETG with CHDM has improved heat resistance.
- Translucency: PETG with CHDM is more translucent.
- Extrusion: PETG is easier to extrude.
- Thermal stability: PETG is thermally stable.
Adding the CHDM is what changes PET into PETG resulting in the listed property enhancements. PETG-HF is doing something more to get even higher melt flow than straight PETG and lowering the viscosity relative to straight PETG while trying to maintain strength and flexibility. More CHDM in place of EG to get to a PCTG is going to result in longer, bulkier chains that eventually get harder to flow at high CHDM ratio.
You’re good to print right out of the bag. Those desiccant packets the put with the spools can dry up to 300 sq. in. so it is practically dry when you open it.