3D Printing with PETG - How does the printing temperature affect strength? || Setup & Tips
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- Опубликовано: 4 июн 2017
- I show you how I set up my DAS FILAMENT PETG filament and tested its printing performance at different hotend temperatures on my Original Prusa i3 MK2. I analyze with my DIY tensile testing machine, how the material strength changes depending on the printing temperature.
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I know I'm resurrecting a very old video, but I just wanted to thank you for the effort you put into your work. For those of us walking down this path, it's wonderful to follow in your footsteps and make our own discoveries along the way. Again, thank you for all that you do.
The difference you observed between a ductile failure when slowly loaded, and a brittle failure when shock loaded is pretty classic actually. When the material is slowly loaded, the polymer chains have time to unwind and stretch out leading to the classic plastic deformation you've observed. When the material is loaded rapidly, there isn't time for those micro movements to occur and the material simply cleaves off. Such clean breaks are pretty typical of shock loaded failures in otherwise ductile materials. If I remember my polymer chemistry from college correctly (and it's possible I don't have it quite right) this tends to happen on the more tightly packed polymer structures.
It's just one of those things that seems to make absolutely zero sense, but it is the way it works out.
Incidentally, this video popped up in my feed at exactly the right time. I'm working on some 3D printed spiral torsion spring designs, and intend to use PETG for the parts. I've been working with some researchers to recreate their study, and it's really interesting stuff. Could make for a fun video if you wanted to try something a little funky and different.
Hey Stefan. Habe kürzlich deine Videos entdeckt und muss sagen, du machst da gute Arbeit. Ich habe mich vor kurzen selbst genauer mit PETG und dem Einfluss der Drucktemperatur beschäftigt. Als Prüfverfahren habe ich dem Kerbschlagversuch durchgeführt. Es hat sich gezeigt, das die besten Ergebnisse mit meinem PETG bei 230°C erreicht werden.
In my experience, print speed is more important for PETG then temperature for good layer bonding. PETG doesn't like fast printing speed. While 45mm/s for normal pieces is quite decent, best printing ( especially bridging ) is around 25mm/s @ 235C ( or for example when printing precise GT2 pulleys ). Lowering print speed reduces the effects of surface tension ( the material in it's molten state right after it leaves the nozzle ) > to observe the effects of this, try extruding a small strand in air and measure it with a caliper... you'll see that the extrusion is always much thicker then the nozzle diameter. While this has limited value for normal layers, it is important for bridging.
An even more important value for bridging ( and strength in general ) is Infill/Perimeter overlap ( I use 55% instead of the default 25% ) which makes a really big difference in quality > think of it as the surface onto which a bridge strand can attach itself.
You're quite right about howto use the pinion teeth and multiplier adjustment....
I'm actually quite surprised that you took the time to do all these tests and forgot to include speed....
Jan Van Haute underrated comment, thanks for sharing 😁
55% huh? Going to try it out tonight
@@albertvillalobos1377 I've been using 50% and been very happy with the outcome. I'll have to try bumping it up a few % points.
I agree, and that's what I find most annoying about PETG. I have to print it super slowly to get good layer adhesion, I print the first layer at like 15mm/sec just to get it to stick well and not peel up on the corners. It's like printing with TPU; can't print fast, oozes and strings a lot.
@@yucannthahvitt251 I print PETG at 40mm/s and it sticks to the bed. I have the bed at 70c. It is a glass bed and I mix a little water with PVA glue and spread it on the glass. The water evaporates the dries the glue by the time the bed heats up.
Hello,
Briefly, about the behaviour of the polymer which can stretch
or break, it depends on the loading speed.
If you apply the load gradually, you let the time to the
polymer chains to move into the polymer and thus it absorbs the energy. The
energy used to deform the part is used to reorganize the structure of the
matter.
If you load your part quickly, you don’t let the time to the
polymer chains to move, to reorganize themselves and then the chains break,
which induce the break of the part.
The same problem happens with the temperature at which the
polymer is loaded.
Hope it helps you and I’m sorry if I made mistakes in writing
this.
Thank you for the really interesting and serious studies you
realized in each videos!
Anyone with a formal education in engineering knows this.
This is called "strain rate sensitivity" where there is a strain rate dependent ductile-to-brittle transition point or range within normal service temperatures. A notch impact test will only show specific notch sensitivity and only ever at one strain rate.
True. Polymers have time dependent Young's modulus which also varies at different temperatures (Probably everyone once noticed this with "Rubber" in his life). So in general, it's really hard to modulate these kind of materials in FEM programmes.
(Bachelor in mechanical Engineering and Master in Engineering Science)
*sorry for bad english
One of the best channels about 3D printing on RUclips ....the first time I saw one of your videos...I immediately clicked that subscribe and like button
Thanks this is super useful, just got some HatchBox PETG and have been wanting to know how to maximize it's strength. Keep up the good work!
Excellent presentation that saves us all a LOT of trouble (and wasted filament) hacking our way through the same calibration and settings tests. Liked, and Subscribed.
Super cool das du alles wissenschaftlich mit messungen aufarbeitest.
Gefällt mir sehr :)
Your video is very informative, and the production quality of the video is excellent. So many videos waste a lot of my time with empty content, but yours is nice and crisp.
Thank you for your compliments! That helps me stay motivated!
I have watched many of your videos. You are very good at this. In depth and scientific . Hope you continue your channel for as long as possible! Cheers....
echt klasse du gibst dir echt immer richtig viel mühe DANKE!
Great video! You did the best test for home users !
You have won a new subscriber with this video. Thank you.
Thank you very much for testing the exact filament I'm printing right now :)
I'm quite happy so far, after calibrating the extruder, it produces prints that are actually a bit nicer looking than what I got from using dasfilament's PLA material.
So in my book, their PETG is the superior material; it looks nicer and has a higher temperature tolerance than PLA.
Great video!! Thanks for the research!!
THANK YOU FOR THIS!!!!
Very imformative. Thank you.
Also, if you play enough with retraction settings, it will definitely reduce the stringing by a great amount
I would love so see you put together some tests for the flex and tension that different materials exhibit. for instance, if you were to make a leaf spring of different materials at different widths and thicknesses and see if they fail under load and shatter and if they dont, how much resistance they offer. And potentially even the compression percentage that they fail at. Love your vids!
excellent video. thank you
Nice, thanks for sharing👍😀
Thanks for sharing 😀👍
gracias. trabajo el petg a 230 grados y realmente trabaja muy bien, voy a probar a los 220 grados y realizar el ajuste en multiplicador de extrusión crear un nuevo perfil en slicer con estos cambios y hacer pruebas. excelente video.
Great video! You should build a heated build chamber to see how heat affects print strength
Love these types of videos! Keep 'em coming please. Any chance you can do carbon fiber pla?
that -10% flow on cura definetly did something, I see an immediate improvement. thanks
I also got my first spool of PETG today.
Servus, Hello, just found your channel , great test and Infos Thanks
I had a roll of PETG I purchased over a year ago and I hated it so I stuck it in my dry box and left. Now I tried it again a few days ago and I absolutely love the stuff. I get a few hairs but for PETG they are very few. Now I would love to get my hands on an all metal V6 and some ASA as I need the heat abilities of ABS but the warping, and shrinking, I can't get it to print in the summer here.
Awesome video, I may have missed if you already did one, but if you could do a video like this for ABS that would be awesome!
Although I'm not a plastics expert, I assume that PETG is very similar to PET, in which case you should bear in mind that when you stretch PET, its yield strength increases. This is the reason that PET bottles (soft drinks etc) are so strong. They are made as small injection moulded bottles, then blown out to full size and become considerably stronger in the process. Another example is the plastic film used to hold 4 packs or 6 packs of beer together. If you stretch a length of it, the material necks down but does not fail there. As the cross sectional area is less than the unstretched material but it supports the same tension, you can see that the yield stress is greater. I think you are seeing this increase in yield strength when you test your samples. It's one of the potentially interesting benefits of PETG over PLA etc.
Loveeee your videos, they’ve taught me so much about printing, have you ever thought about a test to see if adhesion with 3d pens is any different than any other adhesive? I’m sure superglue is the strongest but I’m curious
Surely you could try and reduce the extrusion multiplier at higher temps, as I imagine it becomes less viscous at those higher temps and is more prone to oozing, perhaps increase retraction too?
The bend vs shatter has to do with the plastic viscoelasticity. Basically when you have low strain rates the material can more easily absorb the energy and it does not shatter. So when you perform a tensile test at low strain rates the material will elongate and eventually yield. If you increase the speed at which you pull the sample it will fail (break) at a lower % strain. Typically material "toughness" is tested with a notched izod impact strength where a pendulum swings into a notched specimen and the energy it takes to break the specimen is recorded. Its just a different test to measure a different material property i.e. tensile strength vs impact strength.
You are one good person on earth who is using science to carry forward 3D printing. May be some day, we will use some unit of measurement named after you (e.g. we are presently using Newton, Joules, Watt etc...)
Thanks for sharing :-)
you do some amazing things!!!!
My favourite Material and my favourite Brand. Well done and very informative.
It´s a shame you only have a handful Subs so far.
Thanks. I'd put it that way: the channel sees a healthy growth 😀
Haha remeber when you you had 150 subs like 3 months ago? :D It's crazy how much your channel is growing, true exponential. I had more subs when you started and now I'm still at about 215 :D But that's to be expected, can't upload untill I finish my finals.
It still makes me wonder how did you grow so much. Any tips besides regular uploads, quallity content and sharing on reddit?
Well, you have one more subscriber now! :)
Jep, wasn't actually too long ago. I don't really use social media yet. Also I'm just not able to hold a regular schedule due to my "normal" work. I try to produce content which is not covered by anyone else yet and not only to print the latest Thingiverse models ;-)
Use a filament dryer while it is printing. Pre-drying and drying while printing will keep moisture from being a factor and you will have much better results. It might be a moisture issue or a byproduct of a specific batch of petg, but I've had very good results with my prints from anywhere between 230-260 deg c, and I am also using a Prusa mk2. Anytime that I have noticed bubbling in my prints, it was a buildup of moisture in the plastic.
Great to see another test! are you planning on releasing your design and code for your tensile strength testing machine? I would love to make one and do tests myself. Thanks!
Yes, I will definitely release all of that soon! So many have already been asking for it ;-)
fantastic, I look forward to it!
Great Video. Just wonder what camera hold you are using which I saw in your Video sticked to you headbad: Thingivers?
Greetings! I just started with PETG (purchased at Monoprice) and have found that the lower temperatures work better too. The manufacturer states 230-260 C, so I started out trying 240 C, but my test piece was very stringy and layer adhesion was bad (easy to break apart with my fingernails). When I backed down to 220 C, I didn't have any stings and the layer adhesion was better. Using Wanhao i3 clone by Monoprice (Maker Select Plus), 100% fan speed, 40 mm/s print speed, 0.1 mm layer height, Cura slicer.
+Andy Moore Thank you for the info.
If Polyesters or Polyamides absorb water, the water acts as a kind of lubricant between the polymer chains, just as plastisizers making PVC soft. That's why your specimen kept straining as the polymer chains could glide off each other and align in the direction of the applied force. Materials usually behave differently when strained slowly (tensile testing) or very fast (impact testing). Usually your material shows higher strengths the faster you strain it on your tensile testing machine. The polymers have no time to react to the force so they show a bit higher resistance resulting in a higher tensile stress for example 10mm/min compared to 5 mm/min. Although there is also the effect of extreme polymer chain alignment after slow stretching which results in extremely high tensile strengths. (For examlpe UHMWPE Fibers or High strength Polyester Fibers). Impact is a very high strain rate, so the viscoelastic material has almost no time at all to adapt to the applied force thats why it breaks.
schönes Video
What I do know about some materials, they can display odd behaviour under loading.
Compression shocks like hitting the material with a hammer can put excess strain on the component that then shatters, the impact force of the hammer is transferred and that transfer of energy in to the part causes it to break apart when it wouldn't normally.
Take paper, if you apply enough pressure to a ream of paper, it will explode with some force, theirs an example online with a guy who has a hydraulic press channel and he experiments with crushing stuff.
Well I can't wait to build mine, manufacturer sent it without the right bolts for one part... I have a clone of an i3 which I will definitely be moding.
I print in esun PETG at 240-246C with no bed fan and don't get any deformed prints and they seem very strong. From my experience if you don't use the bed fan the layers hold together much stronger. Esun stuff is great.
Nice, ich nutze auch DASFilament, Finds super. Bin überrascht das es das sogar schon vor 3 Jahren gab, dachte die gäbs noch nicht lang
Polymers are generally viscoelastic, which means it exhibits both elastic properties (like solid) and viscous properties (like fluid). At low strain rate, material elastic properties will govern (e.g: pull it and release before it yields, and it goes back to original shape - like metal). However, at high strain rate, material viscous properties will govern (e.g: stress depends on velocity, not just deflection like in the elastic model) There are also temperature dependent properties as well, so testing polymers in "apples to apples" scenario can be very tricky.
about shattering in pieces....there is one thing called impact. Impact is Force per unit time. Another is thing is called Shear Rate which is shear force per unit time. Polymers have stereoscopic structures and hence behaves differently to different kinds of forces. Also, there is something called Viscosity and glass transition temperature.
genial, gracias
Really enjoy your videos, keep up the good work! Do you have the stress strain data available from the tensile test? If not would you be able to make it available? I'm working on some designs and could really use the data.
Just wirte me a message you you need. I do not use my extensometer for all tests, since it's quite tricky to use. I actually plan to create a database for all of this data but did not have the time yet to create it.
Your charts look basically what I found, 216 degree celsius for best strength w/o overheating
I'm new to 3D printing, currently working on a custom mechanical keyboard project, and printing the key caps with PETG, with 0.2mm nozzle, on my Ender 3, and ended up with a great result after calibration, and about 7-8 failed attempts. :) The following settings work for me: Head temp 145 °C, Print speed 30mm/s, Layer height 0.1mm, Line width 0.21mm, 100% infill since the key caps are tiny parts, Z hop enabled, and had to reduce the minimum layer time to 1s, so it doesn't slow down cause I could not get the tolerances right with changing print speed... For 1st layer Bed temp: 70 °C, Fan OFF, from the second layer onward Bed temp 30 °C, Fan 20% This results in good adhesion, and no elephant footing.
I tried printing it with standard 0.4mm nozzle, but could not get the tolerances to work for cherry MX switches, so I switched to 0.2mm nozzle, and that worked.
Does the temperature change automatically for the temperature tower, or do you have to change the temperature manually with every step of the tower? How do you do configure the printer if it is done automatically?
your tests sound nice. How many times did you repeat it (N?)?
I like your video ,it"s Scientific.Do you try an other direction of printing for the last specimen
Can you please do a tutorial for setting up a temperature test tower using Slic3r PE?
Hi, quite good content, thanx a lot to share this! ;)
For instance, do you offer 3D modeling courses as well?
Very interesting that you had such good results at 220*C because in the 3 different brands of PETG I've used, printing at anything below 240 the layers delaminate in my fingers.
Perhaps my temp sensor is massively off
I think it depends on the hotend construction and filament vendor. For CraftBot printers the recommended temperature is 250C, it sets this value if you select PETG on the touchscreen. In my practice that is definitely good for Esun PETG. I've measured my hotend temperature with a thermocouple, so it is about 250C indeed.
Maybe your cooling fan is too strong. PETG only needs a slight breeze of cooling airflow.
inland specified 240 on the low end for me but it was practically unusable at that temp im at 220+- thats the lowest i dare and the only time stinging and oozing is manageable. i think i tried 210 and based off of print speed the filament would be glossy or an ugly inconsistent hazed much weaker as well. so yeahhh not a a wide window like he has. and trust me ive spent way too much time doing retraction tests with this stuff.
Go buy a inexpensive infrared thermal sensor (their like $10) and will give you much more accurate temps of the hot end than the sensor. Thats what I use on my CR-10S.
I've not seen any PETG that recommends under 230, I was wondering if his temperature sensor is off, not mine. Because I have 3 of them as well as 2 infrared sensors..
Hello, you were wondering why it bends under low load and shatters under high energy load perhaps this material works similarly to non newtonian fluids that are fluid with not much energy applied to them and act like a solid when a strong force is applied because the atoms lock up. I very well may be wrong but that was just an idea that crossed my mind. Thanks for the very informative video and have a nice day!
You should do one more test!
3D print a Thread and see how easily it can be moved/how „sticky“ it is. I noticed huuuge differences there, influenced by multiple factors. Warping, Temperature, Fan etc but most importantly: material.
PETG for example is super sticky.
I've recently printed some M22x1 threads with PETG and I can't say that it is particulary sticky. I printed at 0.1mm layer height. After screwing in metal counterparts once, the threads work really well now. Even PETG on PETG. I was really impressed.
At the beginning he says " It did not stick to the bed properly " LOL Maybe it was - I didn't adjust the bed height properly would be a better way to say that. It bubbles / maybe I had the temp/fan settings off . LOL I have torn many sheets of adhesion promoters trying to get my Petg prints off the printer. I found using glue stick to lesson the adhesion works well with PETG tho. First I adjust the Z height up as much as possible though. I rarely use any of my PLA now because after trying PETG and seeing how much more flexible/less prone to breakage it is ,I try not to use PLA for anything of importance. Glass or mirror with gluestick as a adhesion lessoner works the best for me now. Seriously CNC Kitchen does a great job of building and testing all this data in this video and his videos are very professionally done and have helped me a lot.
i highly doubt he would have made a mistake like that and decent petg would probably still stick. Petg reallly sticks well - the fillament he used may have been a bad or early batch most
likely.
Hey, regarding the strange porperty of PETG , being ductile and brittle at the "same" time. Look into semicrystalline and amorphous plastics (teilkristalline und amorphe Kunststoffe). As far as I can tell PETG is amorphous and i.e. PLA is semicrystalline.
Assuming you haven't already found the answer to your question about strain rate dependent strength and elastic response, it is generally because under low strain rates, the polymer chains have time to move across one another and align (which is the source of the whitening of polymers as they stretch). This process absorbs energy, and you can feel this as heat in the deformed area. Under high strain rates, the polymer chains can't move past one another fast enough to align and their chains break instead.
Most polymers are strain-rate sensitive. Fast strain rate (hammer impact) => break/fail at lower stress. Slow strain rate (gentle loading) => more plastic deformation before failure. It's like oobleck, but much more subtle.
Very nice video, keep them coming. Clear crisp sound. What camera and microphone are you using ?
Thank you! I use a Panasonic Lumix GX80 with the 14-140mm kit lense (amzn.to/2r51Y4z) for filming and a rather cheap AUNA condensator mic (amzn.to/2sNkGin) for the voice recording.
Hi Stefan I have wondered if anyone has attempted to use a pump instead of a fan for part cooling?
I would like to divorce the fans vibration from the printhead and thought of using a cutting fluid tube guide for ease of directing the air flow.
Much of what was discussed goes against things I have viewed in 2020 about this material; would like to see a follow up video with additional testing with updated filament.
in your opinin if PETG can replace ABS
I've seen people recommending a hot air gun pass to melt the stringiness away.
Just heat the gun up, one or two passes ~20cm away, and strings are gone!
(they melt/curl away)
Nice video! Much appreciated!
PS: Somewhere on youtube (i can't remember where ;__; sorry!) someone shot 3d printed discs of petg and it does shatter. Like glass.
Gotta try that out! This is really something that annoys me when using PETG.
JJ CC You mean Thomas Sanladerer!
You printed the Z probes not in serial right? so just two at the time, so the temperature of the previus layer has no time to cool down like it would be on a lager printed part!
I also did some Tests with PETG an found out that if i print them as single probe at the time i could reach up to 44MPA but if i print 3 in parallel, with more cooling to get them cooled down before the next layer starts, they just reach about 15 MPA (all at 240°C)
That leads the question: are the results really representive for bigger parts?
And if both of our tests are made right, will the strength of the adheson maybe increase on higher temperatures for big parts like with PLA but not for small parts like the test probes?
Is it possible that you can publish your findings and results in a written report? I'm a mechanical engineer and work with PETG and PLA regularly as prototyping mediums and I'd be very interrested in your results.
Hi, würdest du sagen, dass das Filament von "Das Filament" besser ist als das von "Extrudr"? Ich habe vor einigen Tagen mit PETG drucken begonnen und bekomme einfach keine ansehnlichen Ergebnisse mit dem Extrudr Filament hin.
Generally I run my fan at 25% and find that is a great compromise between no fan and full fan when it comes to PETG.
I agree with this, PETG needs just enough fan so that overhangs don't droop awfully, but too much fan negatively affects strength. Do some overhang tests, just a basic degree slope without support, to see where your fan performs best around 40 degrees angle to 50 degrees angle. Use as little fan as possible.
In material science, the loading rate of a specimen matters in testing it's tensile properties. Tensile testers are set to a very slow loading rate for this reason. A slower loading rate causes a material to behave more ductile, and a faster loading rate causes a material to behave more brittle. That's why you can't completely rely on the tensile stress data for all applications as your component might be experiencing a fast loading rate due to a high frequency input force
Have you dried your filament? That you get more stringing and bubbling at high temperatures could be caused by moisture pockets.
I find PETG actually easier to print than PLA. It results in better-looking prints and it sticks way better to the PEI-sheet, whereas I have always had trouble getting PLA to stick securely. Then again, I've only used PrimaSelect PETG, no other brands yet, so that possibly has something to do with it.
You should test 3D fuel pro PLA.. it’s designed to print at 230-240 without stringing / blobs
how do we set the towers? thanks
Thank you. Can you test ABS more? I am starting a business and I use ABS to make larger parts that I bond with acetone. I would love more information on how to make my ABS parts stronger. I make accessories for wheelchairs and the parts need to be a strong as possible.
I'd also like to see ABS. PETG is a cool product but in my opinion if you have the equipment to print ABS (simply a hot bed and enclosure) there's no real benefit to using PETG..
People like the claim PETG is all the benefits of PLA & ABS together but it really isn't. ABS is just a beast of a plastic and your trade off is: headache fumes, and you need an oven to print in.. not bad imo.
Personally skipped PLA when I first got my printer, went straight to PETG. It was a difficult journey to get it printing right but once you got it down its pretty easy to use
im at this difficult journey right now, say hello to stringing and spaghetti
what about bed temperature? online resources have a very wide range of suggestion from 50 to 120. great help that is.
on my first layer everything sticks fine, except this tiny little feature that starts as a U and it just loves to stick to the nozzle and bunch up making big blob bringing everything with it and ruining the next feature. it was running fine the first 2 times I ran the print and now I can't get it to work for the life of me.
I think you might be pretty off on the temperatures. Petg should very seldom be printed under 235c, most brands is perfect at 245-250.
I print most brands at 245-250 and that gives good looks and high layer adhesion
feines vdo, dankeschön....
I can brake some parts with bare hand when printed at 230C with fan off .. not the case when printed at 255 .. rock solid.
same here my petg likes being above 250 wont even print at 225
I just got a roll of petg-g supposed it's stronger than normal and is easier to work with
seems similar to a non Newtonian fluid, like silly putty. hit it with a hammer and it shatters, pull it apart slowly and it stretches and stretches, yank it apart and it snaps
This is exactly it. It is called anti-thixotropy. It is shear stress causing the polymers to crystallize and garden very quickly under sudden stress. Over a longer shear time, it has a lower hardness and higher plasticity.
Yep, plastics are mainly non-Newtonian and all behave differently under mechanical stress. this is why iso527-1 standard recommends two speeds for plastics tensile strength test : 1mm/s and 50mm/s ! You should always watch for these two tests when checking A plastics technical data sheet if available. What was your test speed ?
Really good video by the way !
Could you share your print settings with temperatures.
I think temperature is not important without info of layer height and printing speed.
I feel like your testing methods and tolerances should be made into a rating to be added alongside the current tolerance rating that already exists for filaments. Haven't watched this video yet or printed with PETG yet, or rather I haven't printed with anything other than PLA yet and haven't had my 3D printer long ( Ender 3 Pro / I Use Cura ). I also wonder if the best temperatures for each filament should be added as a required or listed tolerance on filaments that are purchased from retailers. I must print myself a temperature tower at some point I have printed some great things already and found the Ender 3 Pro to be a great printer if anyone randomly reading this is interested also. ( RUclips comments can be funny sometimes, but we can always comment on the video and also pass on a reccomendation or review for something associated with the subject or topic and try to help somebody out with a starting place for something be it 3D Printing, programming, writing, 3D modelling, technical engineering, mechanical engineering or anything else such as the many topics that 3D printing can help people get interest in / involved in ) thank you again for this great content and your other / future content now that I have finished the video
In the 7:51 you asked why it breaks with a hammer and not while stretching. That's because every material has different resistance in different ways. By hitting a hammer you put high shearing force in a very short time, which may lead to a conclusion that PETG has low shearing strength. But... as I wrote earlier, hit time was very short, so we should think that dynamics shouldn't be more responsible for damaging probe. Anyway, if you'd like to know more first I recommend you en.wikipedia.org/wiki/Strength_of_materials
Try some eSun PETG... I'd be interested to see how the lower priced filament compares to the more "premium" brands. 😀
The DAS FILAMENT brand is actually even cheaper than ESUN and performs very well. But I think these co-polyesters are not as easy to handle than PLA so its maybe better to stick to name brands. In Germany we say: "If you buy cheap, you buy twice" ;-)
CNC Kitchen where do you buy it in Germany?
I bought it in their online store: www.dasfilament.de/
I don't know if there are any other resellers.
CNC Kitchen Thank you for the fast reply
CNC Kitchen I'm in the USA, and have Amazon Prime, so that's my go-to source... and they carry eSun with free 2 day shipping for Prime members. Das Filiment doesn't seem to be listed, and I didn't see a link to go to an English version of their website (but, I could have just missed it). Do they even ship outside of Germany?
Good methods. Many materials are strain rate sensitive. This is also likely severely affected by temperature. I'm curious how annealing would affect the properties?
That's gonna be part of a future video. But since PETG has a complex molecule structure it shouldn't be annealable. The only effect you might get from a temperature treatment is the stress relief.
Why again did I wait to print PETG till I got my all metal heatbreak so I can go above 240°C or even a above 250°C?
The G in PETG is Glycol.
It's made from corn starch, which is a non Newtonian substance when it's in fluid form.
It might be what makes the material act that way.
G is for Glycol Modified. Normal PET is a copolymer of terepthalic acid and ethylene glycol. PETG replaces some % of the ethylene glycol with another diol such as cyclohexanedimethanol. This messes up the packing of the polymer chains and makes the plastic more amorphous with a lower melting temperature.
The specs for your material would be helpful as not all PETG is the same to compare to other brands as this would change the overall results. Thanks!
wow i didnt know you could print pla that hot!
Cooles Video. Gibt es das auch in deutsch?
Have you (could you) tried annealing the parts?
PETG should not be annealable due to its complex polymer structure, BUT this will actually be content of the next video.
Better parts cooling could help with printing higher pla temps.