Switching from PETG to PLA?  

RE: Switching from PETG to PLA?

I don't know what is the correct procedure, but your idea looks OK. It will work fine.

When I switch filament (quite often), I just load the filament with temperature given by the printer (ie I load PLA at 210 °C, whatever the previous filament was).

RE: Switching from PETG to PLA?

@adesir

I see, so if your previous filament was PETG, you just load PLA in as usual at PLA temp (210C) and the remaining PETG in the nozzle comes out OK at that lower temp?

RE: Switching from PETG to PLA?

I switch between PLA and ABS and sometimes lately PETG all the time no problem. 

Just load it up and flush all of the old color out and it will print fine. 

RE: Switching from PETG to PLA?

@alan-b

I do it like that. Load the new filament at the highest printing temp of the 2 filaments.

From PETG to PLA that would be to load the PLA at the PETG temp and when asked if the color is OK I click 2-3 times on no to flush out more filament.

When you go from PLA to PETG you do the same but use the PETG temp as that is the higher temp of the 2 filament.

So far this has worked for me, but I have read here that sometimes it can be helpful/needed to do a cold pull when switching filament. But I never needed to do that so far with any of the PLA, PETG or PETG HT that I use.

RE: Switching from PETG to PLA?

Posted by: @alan-b

What is the correct procedure to use when loading in PLA after printing with PETG?

Do I simply load the PLA in first at PETG temperature (approx. 240C), to make sure all of the PETG is out of the nozzle, and the PLA is coming out clean of any of the PETG color, before reducing the hotend temp back down to PLA temp for printing?  Is there any problem with loading in PLA (which I typically print at approx. 210C) at this higher temp?

I do have cleaning filament and am also aware of the cold pull procedure, but was wondering if the above would be a simpler and more expedient approach.

Thanks for your advice!

Cheers, Kizzy

Yes, load at the higher temp purge until cleared, and then reduce temp, and I normally purge once more after reducing temp.

Good Luck

Swiss_Cheese

RE: Switching from PETG to PLA?

Thanks everyone for the helpful responses!

@swiss_cheese

How do you accomplish the second purge after you reduce the temp?  Do you just extrude more manually?

RE: Switching from PETG to PLA?

@alan-b

Yes, manually, and you can simply select load filament from the menu again as well.

RE: Switching from PETG to PLA?

@swiss_cheese

Understood.  Perfect, thank you!

RE: Switching from PETG to PLA?

I switch between PLA and PETG most days and always just choose the material that I am actually loading. I do flush it through by selecting "No" a few times when changing material type. I am sure that I can sometimes smell burnt filament when switching to PETG from PLA so would worry about switching from PLA to something much hotter than PETG this way? I don't know if anyone has ever experienced a nozzle clog as a result of burnt filament?

RE: Switching from PETG to PLA?

I would echo the 'No' answer for a few cycles when going to/from PLA/PETg.  Those two are incompatible and the system can't take a joke if it starts printing with one and morphs into another.  I usually do two additional 'No' cycles.

I've also found that some metallics take more 'No' cycles to clear out of the system.