Tips for switching to PETG?
I have been printing with PLA exclusively and would like to branch out into PETG. When you switch filament types (PLA vs PETG vs ....), how much calibration do you do? Any recommendations for working with PETG? Usually I use a little dish soap and/or acetone to clean the build plate - should the prep differ any?
As far as the actual change in filament, it seems that some people here use cleaning filaments and sometimes cold pulls when switching back to PLA, and others simply extrude a little more than extra, perhaps at a higher PETG-type heat. My hope is to get away with the simpler approach...
Re: Tips for switching to PETG?
I'll tell you what I do... almost nothing. I don't change Live Z. I do wash the bed with Dawn and hot water, then apply some Windex as a release agent. I have also started disabling the cooling fan as having cooling with PETG tends to get me very rough looking prints, but you should experiment. I have had great success with PETG and love it.
Re: Tips for switching to PETG?
Wipe the bed with Windex and wipes of the fingers for ease-of-removal. Possibly raise Live-Z very slightly (+0.2mm), others swear by 0.2mm)depending on the filament. Adjust Max volumetric rate in Slic3rPE if I notice extruder skips, speeds in lesser slicers. Otherwise just the default profiles tuned for the filament.
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Re: Tips for switching to PETG?
If you have the textured PRUSA spring sheet, then wash with Soap, then dry, wipe with Alcohol and you should be good to go. PLA leaves a coating on the sheet that PETG does not stick to very well. Going forward you would be better off using one side for PLA and the other for PETG or even get two sheets, if you haven't got a textured sheet yet, I would recommend it for PETG.
I also find that in Printer settings, Z Offset set to 0.025 helps me with print removal for the textured sheet and gives me a better first layer, but this setting is filament brand sensitive.
I also find using PETG for live-z calibration is not as accurate as using PLA, this appears to be due to the sticky nature of PETG.
I also run some rigid ink floss through the printer between changes and also do a cold pull using PLA to get any last remenants of PETG out of the nozzle before switching back to PLA. PETG can be very sticky!.
I would also recommend a silicon sock for your nozzle.
Hope some of this information is useful.
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Re: Tips for switching to PETG?
The Prusa manual says to use painters tape or gluestick with PETG. I, unfortunately, did not read this until after I ruined one of my build plates. The PETG will stick to the PEI better than the PEI sticks to the plate and you can damage the surface (PEI will lift and tear).
Re: Tips for switching to PETG?
Some PETG sticks to PEI like superglue. These types/brands of PETG must be found by experimentation. Always use a release agent (like windex or gluestick) before printing a new PETG.
That said, if you forget and do print PETG that is sticky, never try removing PETG from a warm bed. If difficult to remove from a room temp bed, place the part and bed in the freezer, let it cool a bit -10 minutes- then try removal. Slow and steady pressure is always better than jerking. Once a gap is found, use a plastic spudger to help keep things slow and steady .
On the flip side, I've found Amazon PETG to require an absolutely clean bed. Any Windex at all will kill adhesion.
Re: Tips for switching to PETG?
Also, slow down your prints and you will get better results.
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Chuck H
3D Printer Review Blog
RE: Tips for switching to PETG?
Thank you very much everyone for your advice!
It seems like I should start with Windex, do a test print, and go from there depending on the outcome.
I don't have the textured sheet, so I'll use the flip side of the regular smooth sheet for now.
Maybe this is a stupid question, but is the technique just to apply the Windex and wipe it off, as if cleaning a window? Then wash thoroughly before flipping over to use the other side again?
I have some Matterhackers translucent red to start with.
RE: Tips for switching to PETG?
That wasn't very clear ... I mean, if I have windexed one side, and I then want to use the other side to print PLA, I would wash off the windexed side thoroughly so that I don't get residue on the printer bed.
RE: Tips for switching to PETG?
I switch back and forth between PLA and PETG all the time. At first I found that PETG stuck to the build plate too well and started to remove the build plate surface. At that point I started using hair spray. It helps with bonding and releasing the finished part from the build plate. I use isopropyl alcohol for cleaning the plate. I don’t work hard at cleaning and just remove any plastic and then do a quick wipe with a little alcohol on a paper towel. The plate doesn’t ‘look’ really clean at this point but is free of finger prints and plastic. Then a quick spray with hair spray and print. Works every time for me.
RE: Tips for switching to PETG?
Life got busy but managed to try my first foray into PETG the other day with a Benchy. Strangely, my main problem was getting it to adhere. After two failures, I quit Windex and just used my normal prep (wash plate), lowered the extruder, and slowed it down on the first layer. That seemed to help. I assume this is a less sticky PETG filament and another one might be very different.
