Can not get PETG to print
Greetings,
I am new to the 3D printing world. I have read so much about printing in PETG that my head spins. I am trying to print out the parts for my enclosure but I am having the following problems.
It will not stick to the bed no matter what. If it does it strings and globs so bad it hangs up on the nozzle and makes a constant mess.
So can anyone give me a good step by step process that will help. Like temps and speeds and bed prep.
I did try the blue painters tape but it did not print at all. Should the bed be heated if I use the painters tape? Should I put windex on the painters tape. Should the painters tape be directly on the heat bed or put on the steel removeable sheet?
Help Im at a loss.... im sure it is user error or some settings but I have tried everything I can think of. I would think that the file settings should be correct. Help Help Help....
RE: Can not get PETG to print
This can be a challenge. I have noticed two things about printing PETG:
- The bed must be clean. Use IPA and a paper towel. I put the IPA in a spray bottle from my local hardware store. Spray and wipe with a low line paper towel. I often have to do 2-3 washes with it.
- Make sure you have your live Z dialed in. PLA is more accepting of a Z that is too high and too low. PETG will not stick correctly if you are not in the sweet range.
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Chuck H
3D Printer Review Blog
RE: Can not get PETG to print
PETG is a great material, but can be a bit tricky to print compared to PLA. If you’re aware of these differences starting out, you can save a lot of heartache and frustration.
- If PETG is not sticking to your PEI print surface, you need to clean the surface. Try a dunk under the kitchen sink with Dawn dish soap or your local equivalent. Clean it with a plain paper towel and dry it with another. Avoid touching the PEI surface. Note that Prusa only recommends alcohol cleans with the textured sheet.
- PETG sticks a bit too well if your Live-Z has been calibrated correctly. Most PETG will print fine on the PEI sheet with a spritz of Windex and/or wipes with your fingers. However, hotter stuff (>250C on 80C+ bed) may stick too well. Consider gluestick or some other release agent for hotter temps.
- PETG is attracted to hot metal, so try to keep your bed is at hot as possible and the extruder is a cold as possible at the start of your prints. After the first layer the extruder temperature can be raised and the bed temperature lowered.
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Consider a coated nozzle and/or heater block silicone sock to reduce tendency of PETG to jump onto the nozzle and heater block.
- PETG is prone to snagging onto the nozzle if it’s too close. Some Live-Z adjustment for PETG is recommended. I raise mine (make less negative) by 0.02mm, though others swear by 0.2mm. See what works best for you.
- You don’t need an enclosure for PETG. It’s pleasant to work with at normal room temperatures.
- Keep PETG in sealed bags with fresh desiccant when not in use.
- Reserve one PEI surface for PETG and other hot sticky materials, and a separate surface for PLA.
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He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan
RE: Can not get PETG to print
Hi Bill,
welcome to the 3D printing world!
As said by Charles, make sure your print surface is clean and your first layer is correct ( see Prusa manual). For cleaning your flexplate, just use Windex or some sort of other window cleaner and a paper towel. I use it daily and it works great. Make sure you wipe the print surface dry before starting the print. I always print PETG with the standard Prusa Slic3r settings, which work great for me. The only thing I change is to turn off the Z-hop ( Printer settings, extruder, Z-hop 0 instead of 0.6 ) as PETG is quite stringy and Z-hop only makes it much worse.
Just a another tip, when you hopefully end up with a nice finished print: spray Windex on your flexplate before removing the print, this will loosen up the print from the flexplate so you don't damage the PEI layer.
Good luck!
RE: Can not get PETG to print
Eccellent answer from bobstro above covers most of what you will need to do when using PETG.
One problem with PETG is the type and how much water is can absorb. If as it extrudes you hear popping, thats moisture in the filament. So consider drying it.
Most of the things i print are in PETG and even with filament thats not fully dry it prints well as long as you dont go too fast. I find print speeds are roughly half of the PLA speeds
So first layer keep it slow and it will stick. I use between 20 to 35mm/s
Best add on i got was a silicon sock for the hot end as PETG does make a mess of the nozzel. Before the soc i had to heat the hot end and use a wire/brass brush to clean the stuck on bits off.
RE: Can not get PETG to print
Hey thanks guys. You have been super helpful. I did the windex treatment and slowed down my first 3 layers print speed. I also upped the temps on the nozzle and the bed to 140/85. I also raised the live Z by about .2. It is now printing like a champ!!!
I think I will go ahead and order a new pei bed just in case.
RE: Can not get PETG to print
140 is very low for any filament,.
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
RE: Can not get PETG to print
I also upped the temps on the nozzle and the bed to 140/85. I also raised the live Z by about .2. It is now printing like a champ!!!
That should have read 240/85. Sorry for any confusion....
RE: Can not get PETG to print
That's more like it, the prusa normally stops extruding at about 190C... not sure of the exact temperature...
regards Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
RE: Can not get PETG to print
Think the low temp is about 170degrees may be a bit more. Prusa changed it for a lower temp can’t remember the reason for it
RE: Can not get PETG to print
Think the low temp is about 170degrees may be a bit more. Prusa changed it for a lower temp can’t remember the reason for it
This came up last year. You can lower the minimum allowable extrusion temperature using the M302 gcode command. This came up when someone wanted to use rigid.ink PLA with a recommended 180C printing temperature. You'd want to add something like:
M302 S170 ; Set minimum temp to 170C
M302 S190 ; Reset minimum temp to default 190C
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He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan