Printing with filament type PETG at high speed. Best approach  

Printing with filament type PETG at high speed. Best approach

Hello,

as I will receive soon my MK4, I want to print at high speed also PETG. 🙂 

However, the reality is that almost all "official" sources say that PETG due to its elastic and dense features can be printed only at MAX 60 mm/s 😦 

So my though is, "how can I print reliably PETG with MK4 at 180-200 mm/s if the material supports maximum 60 ?

I have also a FLSUN V400 printer that prints really fast at 350-400 mm/s and all my attempts of printing at high speed the PETG failed.

Reasons of failures were different, but:

• Lots of my PETG was not brand new, and it had humidity, so I had to put the spools in an hot air dryer machine for a day (52°). Even if this improved a lot the print, it is like the material has lost a kind of solvent (it originally smelled when printed, but now it is almost odorless)  and the final quality is not so good.
• In addition from my tests, it seems that high speed influence also:
  - the glass point of the material. Starting from 50 and increasing the speed, the print moves from shiny to more and more opaque.
  - the layers adhesion. The layer adhesion decrease so much with speed increase, that a small force can really break the print, and often the layers delaminates during the print.

I heard that users that owns VORON or BambuLab are able to print at high speed only by using special HIGH-SPEED PETG spools like BambuLab HighSpeed PETG, and only very few other brands. I will try a brand new opened Prusament PETG , to see if it support high speed print. 

If this is true we will have a new prospective of using the MK4 to print PETG at High Speed only purchasing special high speed filaments.

However I don't like the idea of throwing away all my half used PETG spools because they can't be printed at high speed or just use them in slow MK3S mode. 😒 

At the moment I am building tons of sealed DryBox to enclose all my filaments during usage, since it is clear now that even if small humidity amount caused problems at low speed,  it makes impossible to print anything at high speed and filaments should be absolutely preserved.

- Did anyone obtain good print results by printing PETG at really high speed (e.g. perimeters at 380 mm/s, sparse infill 280 mm/s and dense infill 370 mm/s) (of course using a VOLCANO high flow nozzle, otherwise those speed are unrealistic)

I start thinking that PETG can't really be used to do good solid prints at more than 60 mm/s.

Best Regards