3D Printing with PETG - How does the printing temperature affect strength? || Setup & Tips
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- เผยแพร่เมื่อ 4 มิ.ย. 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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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.
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.
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.
7:39 Hi Stefan, I own my own tree removal business and since this biz requires safely lowering heavy logs down on high strength rigging rope a big thing to know about is the difference between static and dynamic loading (aka shock loading). I don't think I know the answer to your question but I thought you would find this shock load test video below very interesting. Dyneema is the strongest known fiber in the world. It's used to make string, cord, rope and bullet proof vests to name a few things. Ultrex is Yale's version of Dyneema. Ultrex is what they use in this ABS (average break strength) test. In the video below, pay specific attention to Test 1 and Test 2. Fair Warning Here: If you watch the other tests then be prepared to mute your volume so the sirens don't mess with your speakers or ears. Or just don't play video past when the sirens start @ 2:30. Here's the video...
th-cam.com/video/WDIo-WZkSaM/w-d-xo.html
Also note, something the video doesn't tell you is about how rope loses lots of strength when a knot is tied in it. Usually about 50%. In Dyneema's case it's losing more like 90%. To counter this, rope pros either pay extra to have their ropes spliced or if they're skilled enough and have the time and feel like it they will just splice the rope themselves. Spliced rope typically retains 90% strength. In Dyneema's case I don't know how much strength it retains. But it Works like a Chinese Finger Puzzle : )
www.google.com/search?q=spliced+rope+strength+test
Search this page for 10% for more info...
www.marlowropes.com/splicing-instructions
Another reason Dyneema fails much easier than other ropes is
because it has extremely low stretch/elongation. Specifically it's 0.46% @ 10% ABS:
samsonrope.com/product/amsteel--blue
I use Samson Stable Braid for rigging (not Dyneema). It has 1.1% stretch/elongation @ 10% ABS:
samsonrope.com/product/stable-braid---coated
Watch this video to see me chop a roughly 300->400 pound piece
off of a palm tree and have it safely lowered to the ground ! >: )...
th-cam.com/video/dSnIvPdeVmM/w-d-xo.html
It depends on the knot, but most knots are more like 40-50% line strength than 10. You have to *really* try hard to get down to 10% line strength for a dyneema knot. That said, splicing it is easy and fun. At least at sizes upwards of 2.5-3mm (and there might be an upper limit where it gets hard again, but I wouldn’t know about that). 1mm is pretty hard to splice, and 1.8 is still not easy.
Huge congrats on your work. I'm new to 3d printing, but since the beginning I'm mainly interested in doing structural parts, so your videos are of great help to decide on the right settings for getting good strength and stability. You rock!
The problem with PETG is that it has both a low specific heat and a relatively high thermal conductivity. This means it cools down very quickly and printing it in a cold room and/or with too much cooling, will definitely reduce layer adhesion. This may explain your varying results over time. An easy way to see when you're cooling PETG too much is to see when the surface starts to lose its shine. If it does, it's cooled too quickly and layer adhesion will become bad.
Recommendations are near 20% cooling for quite every producer, but QIDI Tech, it's PETG Tough is for 400mm/s and 100% cooling. Lot sticky and strong. I had problem with bi-metal hotend and reverted to PTFE at 250°C. Yes PTFE lining has short life at that temperature, but the result is good, and after 2 spools printed I change throat, or refurbish it with new PTFE line.
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
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.
One of the best channels about 3D printing on TH-cam ....the first time I saw one of your videos...I immediately clicked that subscribe and like button
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.
You're so meticulous about your testing, I really appreciate the time and effort you put into your videos!
That's the German work ethic. You do nothing half-assed.
@@DrCognitive American work ethic: Make someone else do it
Great work done! Very helpful for start-up
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....
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!
echt klasse du gibst dir echt immer richtig viel mühe DANKE!
This video is pure gold, when I start to print petg I used 240 degrees thinking that with this temperature I would make the strongest prints, but in the last months I try to print at 220 and I get good resolution quality, through this video I discovered that I obtain also the strongest settings!
Unless your circumstances are the same as Stefan's then you'll need to determine what works for you.
It's a video I saw a long time ago, but take courage to write it.
Based on this, PETG material was used easily.
Thanks again.
this is a very interesting concept. as mentioned below the most impactful setting for pteg is the speed, but the temperature surely has some effect on the ability to bond layers. interesting to see the difference. thanks!
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! You did the best test for home users !
You have won a new subscriber with this video. Thank you.
So glad I watched! Thank you!
0:37 oof that looks so perfect and lovely. those aligned lines. my printer only makes garbage right now!
What printer do you have?
I've been doing a lot of testing with different filaments trying to find a good filament with a high temp resistance for printing RC airplanes. What I've found is that print speed has a much larger impact on layer adhesion than extra heat does. Printing with extra heat just allows you to print faster and still get decent layer adhesion.
Thank you, extremely helpful
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!
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.
THANK YOU FOR THIS!!!!
Great video!! Thanks for the research!!
Very imformative. Thank you.
I also got my first spool of PETG today.
that -10% flow on cura definetly did something, I see an immediate improvement. thanks
Great video! You should build a heated build chamber to see how heat affects print strength
Great video, thank you!
Having found a peak at 220C, perhaps do tests at 210C, 215C, 220C, 225C, 230C?
I was struggling to print petg before your video. Now my ender3 is printing it like a champ! Danke shön!
Could you tell me the settings you use? Just got a role of petg and wanna print it on my ender 3 but can't find a good video or settings for the ender 3 with no mods/everything stock
@@ripcordjack I use 230c on nozzle, 70c on bed. I level the bed to the point where a sheet of paper gives a bit more resistance before moving. And I loosend the wheel next to the extruder gear just slightly. I also keep it slow no more than 30mm/s. And reduce fan speed to 50% max.If the extruder is still popping than while its running you can reduce both the speed and the flow slightly. Also print a fan cover, I had an issue with strings stopping up the fans.
@@suzumes6738 thanks 👍 the leveling isnt a problem at all. Ive been printing with pla a bunch but just wanna try petg to see if it make a difference for my uses. Cause if not imma just stick with pla
@@ripcordjack I find that I need a slightly tighter distance from bed to nozzle with petg, but best of luck to you. It took me hours of swearing before my first good print with petg.
@@suzumes6738 thanks for the help for sure. Yeah that was me with my first prints in general. 😅 It was a bad few hours.
Well ill give it a shot and see what happens and if it doesn't work out ill either send it back or if i can find a local kinda "maker space" ill donate it
Perfect Video. 10/10
Nice, thanks for sharing👍😀
Love these types of videos! Keep 'em coming please. Any chance you can do carbon fiber pla?
Thanks for sharing 😀👍
Nce findings! It would be nice to show the standard deviation of your results on the graphs to have an idea of the variability.
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!
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.
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.
Also, if you play enough with retraction settings, it will definitely reduce the stringing by a great amount
excellent video. thank you
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...)
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
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.
Just got my first roll of PETG to print some replacement components. Printed a temp tower then to test the strength tried snapping it. It snapped super easily, compared that to the PLA, which resisted snapping completely, at least to the limits of my strength. Gonna have to play around with the settings a bit, I guess...
Great Video. Just wonder what camera hold you are using which I saw in your Video sticked to you headbad: Thingivers?
Servus, Hello, just found your channel , great test and Infos Thanks
you do some amazing things!!!!
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.
Nice, ich nutze auch DASFilament, Finds super. Bin überrascht das es das sogar schon vor 3 Jahren gab, dachte die gäbs noch nicht lang
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?
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.
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 ;-)
is there a book or file that is about analyzing 3d printers, because I really need it for the final project.
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!
your tests sound nice. How many times did you repeat it (N?)?
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.
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.
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.
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.
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.
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.
I like your video ,it"s Scientific.Do you try an other direction of printing for the last specimen
Great work done! As usual tho
Your charts look basically what I found, 216 degree celsius for best strength w/o overheating
Hi, quite good content, thanx a lot to share this! ;)
For instance, do you offer 3D modeling courses as well?
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.
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!
Can you please do a tutorial for setting up a temperature test tower using Slic3r PE?
which filament brands do you recomend? not for its usage but for overall quality, where to start?
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.
I am building model train parts. One part is a smoke generator to resemble steam exhaust. We use an oil and heat it to 120-180 degrees. The oil evaporates into a smoke haze. Then we use a fan to blow the smoke out. I have designed and built a smoke generator to retrofit into older model trains that did not have smoke. I used PETG for its High Temp tolerance. Determining the best print settings that result in the highest temp tolerance would be very useful to me. It that something you could do in your CNC Kitchen? D
Thanks for sharing :-)
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.
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!
genial, gracias
The difference in "way" it is broken is because of the speed. When you are bending it or slowly pulling it, the polimer chains and crystal structure has time tu adjust and reorganize so that it doesn't shatter to pieces, but if it is impacted in a short amount of time it can't reorganize but it needs to absorb all the energy so it shatters. So, one is force over "long" period of time, and the other is force over short period of time or the "impuls"
schönes Video
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.
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?
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.
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.
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..
You should test 3D fuel pro PLA.. it’s designed to print at 230-240 without stringing / blobs
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.
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.
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.
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.
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.
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
in your opinin if PETG can replace ABS
I have a question, Im making a cnc that needs to cut soft metal. Wich mototool or spindle is recomended for this job?
Could you share your print settings with temperatures.
I think temperature is not important without info of layer height and printing speed.
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