Why use PETG rather than PLA/ABS? What does the Internet have to say about PETG? What was my experience working with it?

1. PETG for 3D Prin-ng
John Oliva
joliva63@gmail.com

2. Outline
• Why did I look beyond PLA/ABS?
• What did the Internet have to say about
PETG?
• My experience with PETG
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3. Why not PLA/ABS?
• Actually, they are both preRy good and each
has it’s strong characteris-cs.
• But…
– PLA: briRle, limited temperature range
– ABS: fumes, warping, delamina-on
• Rumor had it that PETG had much of the good
quali-es of PLA/ABS with less of the bad ones.
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4. Internet Says (PETG)
• What is PETG?
– A mixture of (P)oly(E)thylene (T)erephthalate and
(G)lycol.
– PET is the most commonly used plas-c in the
world (think plas-c boRles).
– Glycol makes the copolyester more durable.
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5. Internet Says (PETG)
• Strengths
– Very durable, more so than PLA or ABS
– Fairly flexible
– Fairly easy to print (once se^ngs are dialed in)
– Prints without odor
– Very low shrinkage and virtually no warping
– Don’t absolutely need a heated bed
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6. Internet Says (PETG)
• Strengths (cont.)
– Temperature resistance (less so than ABS though)
– Excellent inter-layer adhesion
– Good chemical resistance
– Glossy finish (could also be a weakness :-P)
– Very good for making replacement parts
– Food safe??
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7. Internet Says (PETG)
• Weaknesses
– Can be stringy/oozy and s-cky
– Not very good at bridging
– Recommended to print slower to get good quality
prints
– Soeer than PLA/ABS so it may scratch easier
– Chemical resistance makes smoothing/cleaning
harder
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8. Internet Says (PETG)
• Random Proper-es
– Extrusion temp: 230 – 265 °C
– Glass transi-on temp: ~ 88 °C
– Denser than PLA or ABS
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9. My experience with PETG
• 3D Printer: Wanhao Duplicator I3 rev 2.1
• Finding decent default print se^ngs
– Hot-end: 245 °C
– Heated bed: 80 °C (layer 1), 60 °C (aeer)
– Print cooling fan: Off (layer 1), 50% (aeer)
– .2mm layers
– Same print speeds as I was using for PLA (40 mm/
s)
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10. My experience with PETG
• Observa-ons
– Need to take -me to experiment with hot-end,
heated bed, fan, retrac-on, etc. to get decent
quality prints. More so than with PLA.
– Definitely more of an issue with bridging than PLA.
Higher hot-end temp helps along with higher fan.
– Blobbing and clumping on nozzle can also be an
issue.
– Results can be quite good if se^ngs are dialed in.
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11. My experience with PETG
• Test prints: bridging
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12. My experience with PETG
• Test prints: retrac-on
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13. My experience with PETG
• Test prints: nega-ve space
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14. My experience with PETG
• Test prints: dimensional accuracy
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15. My experience with PETG
• Test prints: mixed
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16. My experience with PETG
• Test prints (cont.)
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17. My experience with PETG
• Test prints (cont.)
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