Why aren't more people 3D Printing this Indestructable Filament?

[@CNCKitchen]

*What's your experience with flexible materials?* Want to get your 3D prints to the next level already today? Check out our Heat Set Inserts and Tools at cnckitchen.store (Free shipping worldwide starting at €100).

[@MrNathanstenzel]

Is that preview image text supposed to say "Thermo Plastic Elastomers"?

[@TheBMWDrifter-sb2cy]

I don't have any, but what type of filament should I use for belts, or like tires?

[@esurfrider7687]

The biggest problem printing with TPU for me has been getting proper layer adhesion along the XY axis. Maybe I need to adjust line width, but for whatever reason the TPU bonds well along the vertical axis but not the horizontal. Any suggestions?

[@innocentidiot9521]

Hello stefan, Thank you for the nice and insightful video! I have a couple of suggestions to test based on my experience with TPE filaments: Temperature greatly changes stiffness of TPU. I have printed powepads for my EUC. at -20°c they shattered instantly from small impact. It was printed from purple transparent TPU from esun which gets to my second point/question: Does transparency or colour affect material properties? I also have parts printed from extrudr medium anthracite (grey), it still holds up fine. I have also noticed creeping issues with TPU. Even under small load they will slowly give up and permanently change form. I have noticed this from several different applications, biggest one was kickstand for EUC which made it unusable because it gave up on one side and will always flip to that side. It worked fine for couple of days until it started to give in. I printed thin PETG supports to fix that issue. That brings my fourth thought, would heat treatment (annealing)help with this issue, or are there TPU filaments that doesn't do that. (It also happens with PLA, you cannot print springs or compliant mechanism that are stored as momentarily "deformed state". It will slowly give in. Also side note: I have noticed PP, to have a considerable amount of friction compared to it's shore hardness. It is also really nice material.

[@henninghoefer]

I printed some inserts for a tablet holder from TPU. It was as easy as you said (bed adhesion is amazing - the brim I added was completely unnecessary) and I was blown away by the seemingly indestructible parts I got. However, they're not as soft as I had hoped. Most generic TPUs you can buy are 95A shore hardness, which is just too hard for the "rubbery" effect I was going for. I want to try 30D next. Overall an excellent video, the only thing I think not mentioned was price - unfortunately, TPEs are all quite expensive, with the softer ones easily going into the 80€/kg range.

[@villekorhonen824]

One thing while printing flexible materials i learned the hard way is to also lower your non-print speeds when printing tall models. Bed slingers tend to cause quite a bit of wobbling and models can get misaligned

[@tim.gromeyer]

So I cam use a very height speed with corexy printer?

[@PJ-oe6eu]

​@@tim.gromeyerAs long as the printhead isn't causing vibrations on the whole printer. I believe input shaping fixes this issue anyway.

[@villekorhonen824]

@@tim.gromeyer No idea, sorry. I would assume that since with delta or corexy the model itself doesn't move in x or y direction the movement speed shouldn't matter. I mainly use bed slinger for my printing and this is the first time i encountered this sort of problem with any filament. I admit i was also bit greedy and wanted to cheap out on structure and some of the supports and adding some more mass to model made it a lot more stable.

[@villekorhonen824]

@@PJ-oe6eu I mean the whole model was physically shaking when moving on Y-axis :D

[@qaywsxefb]

The issue with bed slingers is not speed but acceleration. So you can keep print speed on "bed-axis" but drastically decrease acceleration. You could also reduce acceleration by height, so the total print time is even lower

[@hebijirik]

Someone in the Rat Rig Facebook group gave me great advice that really works: When the print finishes rather than tear it off the bed pour a little bit of isopropyl alcohol or similar around its edges. I had trouble with phone cases that kept getting deformed when pulled off the bed. This solved it completely. The alcohol gets under the print I think via some capilarry action and almost releases the print from the bed. The force needed to peel it off the bed is reduced to something that feels like 10% of what it was before. I have tried it with several TPUs that before tended to damage my powder coated PEI sheet and it works beautifully. With G10 smooth surface it works too but a bit slower. After getting it off the bed this way I just have to let it dry out the alcohol from its pores.

[@MartianMoon]

I do the same thing but I keep my isopropyl in a spray bottle, & spray it at the base I also use a flexible bed which helps a lot

[@hebijirik]

@@MartianMoon All my beds are flexible too, but especiall with relatively low height parts with big foorprint the printed part is sometimes more flexible than the bed 🙂. I buy the IPA in plastic bottle with a tiny opening on top so it is easy to squirt a thin stream of it around the base of the print too.

[@uhu4677]

Nice! I will try that out.

[@BaghaShams]

Does this eliminate the need for a glue stick?

[@hebijirik]

@BaghaShams for textured PEI and G10 I know for sure it does. I never use glue stick. I am guessing that for smooth PEI it works also without gluestick but I don't have one to test it.

[@webx135]

4:22 "I can't really wrap my head around what to print with this" Oh I think you already know, judging by what's printing in the background. I'm sure Mrs. Stefan is quite pleased.

[@MakerBees333]

Oh, those German stereotypes strike again 😅.

[@LouisLeXVIII]

But... Layer lines 💀💀

[@MakerBees333]

@@LouisLeXVIII TetraHydroFuron smooths TPU like acetone on ABS… but it is not safe compared to acetone. … just incase anyone wanted to know 😉

[@writer8706]

so i wasnt the only one that noticed.

[@voidtype]

then the same filament found its way into "any small crack it can find" @ kzbin.info/www/bejne/anrRd5dredSNl5Y

[@ndisa4444]

4:20 What are you printing there Stefan? 👀

A "test cylinder" ;-)

[@dextrodus]

I mean he was thinking HARD about what to print it seems

[@willcubemakes]

What do you think?

[@lickytime9683]

​@@willcubemakesDILDOOOOOOOOOO !!!!!!!!! FLEXIBLE DILDOOOOOOOOO !!!!!!!!!!!!!!!!!!!❗️❗️❗️❗️❗️❗️❗️❗️❗️❗️❗️❗️❗️‼️‼️‼️‼️‼️‼️‼️

[@spedi6721]

​@@dextrodusmaybe we get a clue if Stefan releases a video testing 3d scanners in the near future.

[@tsbrownie]

The flexible filaments can be used to print replacement covers for electronic equipment. For examples, the little "hatches" on cameras that cover the HDMI, phone, mic... plugs. These parts are often not available (especially with older cameras) and so worth printing.

[@TheBoatPirate]

THAT, is a GREAT IDEA!

[@GordLamb]

My favorite use for TPE is printing gaskets, though I'd really like some purpose-built ultra-soft filament with excellent chemical resistance specifically designed for it.

[@FilamentStories]

So much information-and work to get this all together for us in a highly organized package. You're the best! (Aside: I've had the Recreus 60A for I think two ears now and I still haven’t decided what to print with it!)

[@richardbertacchi5016]

Hey Courtney! What's the story on why hardly anyone makes a hard (50D to 70D or higher) TPU? (THANKS, If anybody knows it's be you)

[@ciaduck]

Used TPU to 3D print a door stop. I was looking at all the poor designs and lamenting spending $5 to $10 on crappy commercial one made of rubber that I had already seen fail. So I designed and printed some. The other benefit is that it can be easily modified for larger gaps or heavier doors. They work well out of TPU, and cost me literal pennies to make.

[@piquat1]

I also made my own door stop. Needed a tall one that could take a beating. Plus, when you work out the weight its cheaper to just print it.

[@XA--pb9ni]

I legit allways use TPU when possible. It is basically indesctrucable ! And The Layer adhesion is sooo good. I have 2 Waterbottle holders for my bike printed in TPU, every other material cracked after a while cause of the impacts of the full waterbottle but the tpu one still works just fine!!

[@Saeschboy]

Can you recommend some very hard TPE ? I have some TPU over here but it's very soft and hard to print on my ender 3 with Bowden drive. I don't know the shore hardness. I don't even know the brand.

[@tarakivu8861]

@@Saeschboy You can just buy hard TPU, most is quite flexible, but some sell multiple varieties, including hard ones. Basically indestructable to hard forces.

[@spehropefhany]

Even with direct drive and using external feed the very soft Ninjaflex TPU doesn't print well on an X1C.

[@oliverer3]

​@@tarakivu8861It's a shame the hard TPUs are so expensive though. Anything above 95A is ridiculous. There is 64D and 74D hardness TPU available which sounds incredibly useful but it's like $1 per gram.

[@FlashBIOS]

What brand of TPU do you use? I only have experience with one, and I wasn’t too impressed.

[@sasjadevries]

17:54 That moment of inertia formula that you used, works for rigid bodies. For a pipe it's only relevant for determining its resistance to buckling, but for comparing the overall stiffness of the pipe you'd want to use a formula where you take the area times the distance to the centroid axis.

[@andreask.2675]

I actually slightly oil the bed for TPU: Put a drop on the PEI and distribute it. Then wipe it off with a dry cloth. Works great for me. (I use some fine mechanics oil.)

[@JJFX-]

That's actually a good idea mate and easier to clean up than glues. Another tip for anyone struggling with with ABS/ASA (which is mostly what I print) is to clean a smooth PEI sheet with a SMALL dab of acetone on a clean microfiber cloth before every print. This should not damage it but do not squirt it directly on the bed or when it's hot. IPA does not clean as well as you might assume and glues can actually cause problems. If you can't use acetone warm water and dish soap is still better. If you find it sticks too well you're probably using a hybrid material and not true ABS. I've never run into this but some have told me there's some filament that sticks almost like PETG.

[@sdfgsdfg3789]

Man, I wish there was an ultimate filament properties chart. Where all types and brands can be compared to each other.

[@kadensmith5586]

That’s a great idea, shocked no one’s done it.. would be down even for some heavy monetization if any board software developer may be reading this.. 😂

[@blehblehbleh2003]

Prusa has a table with many materials and brands on their site that is really simple and intuitive. I’ve used it a couple of times to check the best brand and material for some of my projects :)

[@HorochovPL]

help.prusa3d.com/materials

[@tarakivu8861]

Isnt there a website showing comparisons already?

[@anon-means-anon]

Slant 3d is gathering up test equipment to do just that. I can't wait.

[@mr_voron]

This is the video I’ve been waiting for. Thank you for struggling through these tests! Your sacrifices are appreciated.

[@CNCKitchen]

Appreciate it! This was way more work than anticipated yet I still feel there is so much more to talk about and test.

[@urmoderngamr]

The current best use for TPU for me personally has been airsoft and cosplay, TPU is fantastic for Absorbing BB's in armor. And the flexability make it super nice to wear aswell

[@squishinstix]

They use TPU as armor in motorcycle jackets

[@honkbeforeitstoolate587]

Do you have a link to your airsoft armor?

[@RocktCityTim]

... and Every Bourbon is a whiskey, but definitely not every whiskey is a bourbon! The maximum volumetric speed was one of the best discoveries that I've made in 4 years of printing.

[@rsquared9703]

I print directly out of a dryer for all filaments due to my short story... My first roll of TPU was Creality green. I printed with it on an Ender V2 and didn’t have great results. I learned about drying and used a dehydrate function on my air dryer to dry. Prints would start great then fail halfway. Long story short, It absorbed moisture so fast I could dry for 8 hours and within 2 hours it was bubbling again. I threw away about half a roll of TPU because I couldn’t get it to print reliably on 3 different printers. I changed TPU brands and now I have nothing but great results.

[@momobhc]

Even through a bowden tube I find myself using more retraction than is ever recommend for tpu. I like to use the purple glue stick because of the PVA in it. Drying the filament makes the biggest difference! Another really good TPU is the Ninjatek Armadillo. It's tough as shit, and you can print it faster. It has great industrial applications, and I feel it's being slept on.

[@tenchuu007]

I replaced the broken tires on my luggage with TPU. Works a charm.

[@jonathan7744]

I've been printing Sunlu TPU 95a at 11 mm3/s. I've never had much issues with it, but if I'm printing more than one part on the build plate it will string quite a lot.

[@rescuemethod]

your friction tests...the surface finish of the sample has a huge effect on how "sticky" it is, resistant to forward motion. So then the same material but printed with a smooth vs textured surface will perform quite differently. To add complication they will perform differently in wet vs dry conditions. The supersoft material likely deformed during the test, creating more surface area in contact with the ground surface.

[@leonnundel2443]

Also the coefficient for sliding friction will never ever exceed static friction. There is no other way except there being loose particles building up while sliding adding up to the drag

[@ronyadin3958]

Im glad you tested coff of friction, up until now i would print tpu and coat it in plasti dip, but now i know what tpe to try for application where i need friction. Thanks!

[@andreasherzberger812]

I have already printed a lot with TPU 95A and TPU 60A on my Ender 3 Pro. And yes it is with bowden extruder setup (and a Phaetus Dragon hotend). I printed gaskets, some boxes for tools and dampening feet This video comes just at the right time for me because I want to try new flexible materials. Your tests were very helpful to learn about the properties of TPE's from different manufacturers. Have you ever tried SBS filament? SBS schould be a bit more grippy. I would like to test SBS, but have not yet been able to find a supplier in the EU.

[@themoon69420]

Just a word of caution. 3D printed adult toys are risky. They can break off inside you and cause you to have to make a very embarrassing trip to the emergency room...

[@mrtechnophile3483]

Reminds me of the warnings for 3D printed food items, which mention the inter-layer crevices where bacteria can grow.

[@huntermitchell761]

Inside you? What if they're used...outside you?

[@themoon69420]

@@huntermitchell761 Not as risky in that case. 😉👍

[@32BitJunkie]

Aside from bacteria

[@Vukuzenzele]

A tip to prevent things from getting stuck inside you is simply not putting it there in the first place.

[@Jack-ny7kn]

I didn't know about that max volumetric setting. That tip alone was worth the watch. I print a lot of engineering grade stuff like nylon and asa, and it really helps to slow the prints down, so I will be using that a lot now. It helps prevent thermal runaways, gives better layer adhesion and dramatically improves the print quality. It even helps with stuff like printing round holes in a perpendicular orientation (they come out more round and less squished looking). I avoid overhangs like the plague because the part cooling fan loves to induce thermal runaways at high nozzle temps, but I would assume it would also help with overhangs and bridging. Probably also help with making supports easier to remove with tricky filaments that don't like supports, like nylon. It's actually interesting how much of this video applies to nylon just as well as to TPU. Right down to the gluestick lol. I actually have really really good results printing nylon on the Prusa satin sheet with a little gluestick rubbed on with IPA. I wonder if that would also work for TPU?

[@luke_fabis]

Copolyesters in particular tend to bond really well to PETG. If you have a multimaterial printer, it opens up a lot of design possibilities.

[@luke_fabis]

@@huntermitchell761 I don't understand. PLA is not a copolyester, and 60 A is a Shore durometer rating, not a material.

[@huntermitchell761]

@@luke_fabis oh I'm stupid nvm

[@marsgizmo]

This is a valuable video! Many thanks for your efforts in highlighting all aspects 🙌 ..and happy you like the Filament Bunker :)

[@CMDRunematti]

You could use it for RC car chassis, ship hull, or plane wing. Set it to be strong enough to take the lift and air resistance, but soft enough to not break if you crash. If it can withstand fuel, like gasoline, you could store fuel in the wings like real planes, and integrate the fuel tank into the chassis to save space

[@peircedan]

I have used common 95A TPU on many items. Never have done any drying and my results are good. Stringing does occur but I am usually using TPU for less complex designs where there is not a lot of stringing and removing it is not a big deal. Regarding adhering to my textured PEI bed I just use no heating on the bed and removal is not that bad. I typically use TPU as a shell to install over a PLA case for impact resistance.

[@jasonshallcross2741]

I print TPU quite a bit, and I have a bowden extruder, I've also never needed to dry the filament, despite living on the coast in England. You do need to print a bit slower, you do need to look at retraction and you do need to get the temperature right. Strangely I find 225c is usually fine.

[@MrGerhardGrobler]

Great video! I 3D print nosecones for my model rockets. Double wall, 5% triangle infill. Creality CR-TPU. Not much bounce. But I want it to survive the landing. And it accepts paint!

[@huntermitchell761]

Why are your model rockets hitting the ground that hard?

[@WindCatcherRC]

We use TPU for motor mounts on one of our RC plane kits. The plane is used for full contact combat. I have never had a motor mount break.... yet. Thank you for this great video. Gives me more to think about for future R&D.

[@rm4po4]

That sport sounds crazy.

[@WindCatcherRC]

@@rm4po4 It's amazing when you get 10 airplanes in the air at one time. It's best if we focus on flying in formation first and then try to make contact. Otherwise it becomes a big ball of nothing for 5-10 minutes.

[@huntermitchell761]

​@@WindCatcherRCgot any videos?

[@WindCatcherRC]

@@huntermitchell761 Sorry, for now we don't have any videos of full contact combat. We are swamped with work which is a good problem to have, however it means we don't have time to keep up with KZbin videos. I'm hoping to get to a point where we can start doing videos again in the future. There are other people who post full contact combat videos.

[@hinkepank1239]

I had printed TPU before ( maybe too wet as I learned right now ) and the results were acceptable. Lately I switched to a 0.3mm nozzle and I just tried to print my TPU again with a total failure. So I learned the hard way not to print TPU with a 0.3mm nozzle but that gives a hint to try it with a 0,6mm - maybe this gives even better results. Thanks a lot for your very interesting video !

[@JakJakku]

On smooth PEI you definitely need a release agent but I find that it's not a problem on textured sheets, and print on them with no additives. Adhesion is strong but not dangerously so. But do a quick test in a corner before you risk ruining your sheet!

[@ottomuller4948]

Hello Stefan, can you make a video on the subject of fine dust and 3D printing, as well as the vapors when printing ABS/ASA and how best to deal with them?

[@FirstLast-vr7es]

I designed a 3d-printable Ankle/Foot orthosis (FIDIM) for use with Nylon. That works great, but I've always been extremely impressed with the durability of TPU materials. The hinges on FIDIM are made from it. I'd really like to try a stiffer TPU for these now.

[@rcmaniac25]

I love that you did this. TPU (and TPEs) are some of my favorite materials (I have from 70A to 75D filaments). Depending on what I need it for, I sometimes don't bother with drying. Drying gives better surface finish, less strings, and probably better layer adhesion... but if all I need is for something squishy, then it's not as important. I've used it for HULA, phone cases, bumpers on rolling tables, wheels on vehicles, kids toys (seriously, all of you printing Toys for Tots and kids toys in PLA and PETG and ABS... print them in TPU instead. They'll be virtually indestructible, make less noise when they impact the ground, extra walls or higher shore hardness means you can make "non flexible" toys out of flexible materials and not damage walls, floors, etc.). I even had a vacuum sealer that had a custom attachment... I designed and printed an adapter out of TPU so it could be used with the standard circular vacuum seal points on generic vacuum bags, and one model I plan to print soon says to print the o-rings to make it water tight in TPU. It can do a lot, and certain brands come in WAY more colors then the 2-5 that many other brands have. May be a case of "US vs. EU" but I feel like the OG king of flexibles was missing: NinjaFlex. And on top of that, one of the most popular filaments, PolyMaker, also has a whole collection of flexibles. Many PLAs start as NatureWorks PLA resin 3D850 or similar, but I can't say "use one TPU, and you've used them all" so would love to see some of the big brands rather then just the EU brands. Outside of that, only real missing item: print on a textured sheet and you can skip the gluestick. It still sticks strongly, but you can peal it off without damage. The airless basketball has been such an interesting one to me... when everyone was going nuts over them, they used PLA. Before seeing the first full video on it, I went "it will bounce at least once... and then crack because PLA doesn't like impacts". And many learned that. PETG (more flexible then PLA and ABS), ABS, they all did this in the end. Finally, someone did TPU... I went "wait, why did you use 95A? That's gonna hit the ground and squish" and it did. I didn't have much reference point on bounciness, so I opted for a 75D TPU so it would be stiff enough to rebound... but still be flexible enough to handle the impact. 100% scale on the XL. It lasted well, some 12 bounces or so... then I tried it on a driveway and it bounced twice. The 2nd bounce, it caught a rock and that little extra bit broke the fine mesh of the ball and it cracked. So while people went all over the materials, the real interest was seeing the 3D models... the one you printed (PartyLime) seems to have done the best "reproduce the design with double lattice structure" that gives it some strength and ability to rebound where as many others basically just made a hollow ball with holes. Actually, looking at it... he apparently released a version and worked with a filament maker to make one with near identical bouncing and supposedly tested it on a court, which is impressive on how far it's come. $2500 vs. $60 and the will power of 3D printing community.

[@TheElectronicDilettante]

I’ve only just recently started in the 3d printing hobby. Channels like Your’s Made with Layers’ and Z. Freedman’s are not only my go to resources when I hit a wall but you guys set the standard for Making, 3D Printing, ECE and how they’re all connected. Being a rookie, I learned the hard way about moisture, I’m working on sourcing some dedicated filament dryers. In the mean time, I have a food dehydrator. I’ve seen one a few times in your videos. Will a food dehydrator actually do the job? If you have a video on that specifically, please point me in that direction. Thanks for the video and your time.

[@GalEhrlich1]

Thanks

[@CNCKitchen]

Thank YOU!

[@Zewwy_ca]

Amazing work. I really love the amount of data you provide in your videos it really helps when designing stuff. I have never printed a TPE filament, but with all your shared knowledge maybe I'll eventually give it a shot. Though I don't have a "Modern 3D printer" I still maybe limited.

[@srboromir452]

Got some esun tpe 83 on sale last month, been having fun with it Made a phone case out of a foaming flexible years ago, loved it

[@grappeq]

If you despise glue stick like myself you can try spraying IPA on the plate while removing the print or heating the bed to 100C before detaching it - both methods work for me almost always.

[@dr_fish]

I'm surprised that this video never mentioned flexible PLA. I've become a fan over the last few months, it's so nice that it adheres well to regular PLA. I recommend checking it out.

[@robertd330]

That sounds interesting. Can you recommend a specific brand that you use?

[@dr_fish]

@@robertd330 I use Flashforge. I use the exact same settings as for my normal Polymaker PLA but I slow down to either 1-2 cubic mm/s or 15-20 linear mm/s with similar results. That's just with a Prusa Mini, so you could probably go faster safely with a different printer. Basically, I just treat it as a color change and then use a modifier to slow down the speed for combined material prints. For all-flex prints I go the volumetric route.

[@unc_matteth]

how are you getting that shiny black finish? i don't think i've ever printed anything so shiny. is it special filament or a certain settings? that looks awesome. does it get fingerprints though?

[@kriskeersmaekers233]

Cura, in their infinite wisdom, actively rejects community efforts to add a maximum volumetric flow rate into the slicer.

[@BenChilds]

Thanks for the hard work on doing use cases and examples to demystify these filiments.

[@Ttt-n1w]

Pretty cool! Very in depth and your research gives a lot of good info for designs with these materials. You didn't test compression strength, however. Also, you should augment your stress tests by noticing when plastic (*pun*) deformation takes place. You'd have to ladder your tests and compare relaxed height to notice. With these flexibke materials especially, it's hard to tell when it was a partial deform vs a complete break, and this augmentation would help inform this.

You can also measure the static coefficient of friction by putting the material on an inclined plane, and increasing the inclination angle until it starts sliding. You can easily measure the coefficient of friction from the angle: f = tan(angle).

[@bigrattila5]

9:33 I have an instantpot airfrier that has a dehydrate mode. It fits two spools at a time and leave it running overnight. I also put in desiccate packets and when done, put both in a diy dry box with a bowden tube.

[@MOVIEKICKS]

Thanks for the video! In particular, thanks for the range you give for Max Volumetric Speeds. This will come in handy as I start experimenting w/ softer tpu / tpe.

[@Pcoakaloid]

You can print colourfabbs varioshore tpu on the prusa mini. You have to loosen the extruder idler wheel screw by 3 complete turns so it doesnt jam up. Works great.

[@armorhide406]

Have you seen NathanBuildsRobots address the risks of fiber filled filaments? Highly recommend you be more careful with carbon and glass fiber

[@JeSuisNerd]

I don't have a filament dryer (or heated drybox), but with my regular airtight storage bin with desiccant I am able to successfully dry my TPU by placing the whole box where the sun would hit it by a south-facing window. I just use a cheap 2-pound pack of color-indicating silica gel beads, and recharge them after the first day or two. It takes a bit of forethought, but after 3-4 days it prints like a dream. This will be faster in warm climates, but up in the chilly midwest it takes a bit of patience!

[@cyanohibiki0616]

I was looking for information about printing flexible material with my Prusa yesterday, and today Stefan drops this great video. What are the odds!

[@Hasitier]

Still printing flexible filaments with my trusty old cr 10 mini since years. The only modifications to the printer are a dual gear metal extruder with a hand made guide to prevent escaping of the filament while getting pushed, a bed level sensor and a Buildtak surface on spring steel. And yes still using the Bowden setup, no direct extruder. I am able to print soft TPUs like Ninjaflex with it. Just going very slow.

Hard TPU is my default filament! Probably harder than any in this test, 70D or so.

[@richardbertacchi5016]

What's your go to hard TPU? Used to be able to get decently priced 70D from KVP but they don't appear to make it anymore. Ninjaflex Armadillo gets too rich for my blood pretty quick.....

[@ThantiK]

Finally, someone who gets it. We should all be focused on _harder_ TPUs not softer ones.

[@richardbertacchi5016]

@@ThantiK So much easier to print than nylon/pc/whatever technical filament you got. Someone should ask/beg Polymaker-Prusa-Greengate-Inland-Sunlu-ESun to mass produce the stuff. I've made gears out of 70D TPU that are stronger and more resiliant than the original injection molded stuff. Why can't we have nice things? lol

[@xavy_]

@@richardbertacchi5016 New to 3d printing here, but isnt nylon a better choice for gears because of its self lubricating nature and higher temperature resistance?

@@xavy_ harder to print, but probably yes. I don't have an enclosed printer.

[@matyasiadam4656]

I use Recreuses filaments. They absolutely must be dry in order for them to work, but when dried properly i crank up the temp usually 240-260°C and they print well and relatively fast 4-5 mm3/s for a hardness of 82A. Also very important to have a filament path whit as low drag as possible otherwise extrusion will be inconsistent.

[@alwAudio]

I love flexibles. The results are so strong and have lots of uses. I've made replacement feet for an aluminium work platform where the original feet had gone brtittle and broken. Also made Shimano hydraulic brake bleed nipple covers, the originals are really soft and easy to lose when cleaning the bike, the TPU ones are bright green and look cool and are easy to find. We've used it at work to make masking covers for PCB connectors on boards that need conformal coating, much quicker to fit than masking tape, more precise and easy to remove

[@SIMD007]

Great video, the amount of work required to create a video of this quality must have been huge 👏

[@Roobotics]

Thank you for finally explaining something, I've never had to dry my filaments to get reasonable surface finish, even my black TPU. I guess it's because I print my filaments at the lower temps. Usually 220C for a roll I have sitting out in 30-60% humidity..

[@hoggif]

I keep my filaments in plastic boxes with plenty of silica gel on bottom. (dirt cheap if you buy the kitty litter quality in large bags). I have a kind of bowden style tubes for filament takeoff. I mount the selected ptfe tube close to printer and the rest of tubes loop back to a quick link connector on box. Any large enough box will do and some tubing can be mounted to hold several rolls in a row. Food drier and/or vacuum are some methods I've used to dry other filament. After they are dry, they keep dry and print from the box.

[@GlennBrockett]

I'm glad you touched on the moisture issue. I have watched a filament go from dry to moist in 3 hours during a print. I know there is no "Glass transition temperature" available for TPU, but at what temperature does it generally deform?

[@croustibat682]

You could print computer fan gaskets/vibration absorbers with the 60A TPU. It should be great at sealing the surface and limiting vibration transfer to the case. As far as moisture goes, i use an ikea samla box with 4 rolls in it, and about 1 kg of dessicant. It works well enough :)

[@fabianmerki4222]

just print it while drying in a food dryer. 20min heating at 60° is enough, saves a lot of energy.

[@grepmonkey]

I've had good results with a similar approach. Completely drying filament on the spool takes forever. Placing the filament in a dryer I can print from and drying for an hour or so and then starting the print while the dryer continues to run has made for a time saving process. I use the two Sunlu boxes shown in the video this way.

[@AleksandrEfimov]

@@fabianmerki4222 It depends a lot on the climate/humidity. I have 50-60% and higher air humidity almost all the time, so I need to dry filaments a lot. Surprisingly, PLA needs less drying for a good print; and TPU - the softer it is the more drying it needs. Up to 6-7 hours. For my softest TPU I sometimes respool 100-200g of it and dry it separately right before printing - only this way it works...

[@blackpro303]

I have a Flsun Super Racer, and for those who know it, they will understand that it is difficult to print with TPU (95A shore) because it has a really long bowden tube. However, I managed to create a profile on Cura that allows me to always get "good prints," at the expense of a bit of stringing. The main problem I faced was the retraction speed. I spent days adjusting that value, but nothing seemed to work. So, I solved it simply by removing the retraction. To compensate for the stringing that forms, I raised the Z-hop speed to 200 mm/s and the travel movements to 350 mm/s, thereby reducing the probability of stringing. As for the brand of filament for the TPU, I used ZIRO.

[@eideticex]

For me the biggest help printing TPU has been to use an extruder idler that only grips tight enough to move the filament. I found an idler squeezing too hard will deform the filament as it enters the hot end. While the resulting part may be very resilient the filament itself is kind of pliable with the TPU I have used.

[@silencedfrost901]

few key takeaways when I do my tpu tuning, I'm not sure about it's shore hardness but I first tested the vol flow by extruding at a set speed, resulting in 5mm³/s, set that in the slicer, the. proceeding to flow, pressure advance, then retraction, finally got my pa to 0.32, flow rate 1.0, retraction 0.9mm at 30mm/s and yeah, having tpu dry is REALLY crucial to get a successful print!

[@ciaduck]

For TPU, I disabled retraction. I print with 30 C bed heat. I also had great success printing at 230 C. I came by the 230 C by manually pushing the filament while heating and picking a number 10 C above that. The on spool recommendations seemed very high to me given that TPU liquifies at a lower temp.

[@TheTsunamijuan]

One of the best investments I made for 3d printing, was dedicated filament dryers for machines. Its made printing things like TPU, and Nylons a extremely reliable process. I live in an area with an average humidity of 95%. Air conditioning is also not common. So Not only do i dry my filament before printing. But I run the dryers while printing (requires a bit of thermal tweaking on filament profiles for temp based on time and flowrate). When printing TPE's at 0.04mm layer heights and a 0.2mm nozzle, you can see a noticeable difference when you hit areas that have high humidity, as it causes the dark filaments to cloud and lighten.

[@JohnUllrey]

Great tips on printing TPU, thank you! Retraction settings make a night & day difference.

[@roboman2444]

I've been printing un-dried TPU on a bowden tube extruder for years. Yolo. I guess most of my success has been printing it at 230 and slowly.

[@ry7hym]

same lol it prints like shit

[@SWREngineering]

I have printed TPU stuff on an Ender 6 with half a meter Bowden and TPU that's been laying in the basement open for a year.. yet to have issues. Probably just dumb luck. Extrudr Flex Hard was no issues..

[@argy8141]

Bowden Ender 3, I can print TPU without issues, but if it's undried it spits and blobs. It's awful wet, get it dry and it's acceptable. Now moved to a direct drive neptune 4 plus and it's night and day. Lovely prints but still needs drying in the UK before use.

[@libhranan]

I wonder if the very soft materials had a friction coefficient over 1 because they deformed and increased contact area once they started sliding?

[@florihae]

I am really in love with my EIBOS Series X: Easdry Filament Dryer. It is super cheap (50$ including Shipping) it is small, can be directly printed from. Has a fresh air fan (so actually is able to remove moisture) and is quiet. I print directly from it, so drying is only required for 1h or so and while printing. Perfect results!

[@evilc2048]

I use PEBA a lot. I used to use TPU95A or 98A, but I found PEBA to be even better. My application is parts for FPV drones - they take a LOT of physical abuse (eg flying into solid object at 50MPH) It keeps it's elasticity down to a lower temperature. It bonds well with Nylon - an inner core of Nylon and an outer coating of PEBA is insanely durable and still quite rigid It's lighter than TPU

[@planckstudios]

I sand some functional flexible parts before using them. This dramatically increases the grip/friction

[@Gryfang451]

I had an old printer that printed TPU with no issues. My newer one always jams. Both are direct drive. But you got me thinking about retraction. I need to check that. The filament I'm trying to use is really flexible, and seems to be jamming at the gears. Maybe trying less retraction would be a good idea. I stopped using ZHop completely on TPU and it helps with stringing quite a bit. Also helps on PETG for the same reasons.

[@SMAMaggot]

I tried a 90A TPU from Monofilament on my bowden Ender 3 with an Aliexpress dual gears extruder. I repaired with printed replace gaskets my old tap mixer with weared ones. Also I develop custom seat heating system in my car and my wired with a DC connector on its ends is protected by TPU cases. This type of cases also protect from short-circuiting and over-bending my signal cables connected to delay relays in my home automatic transfer switch (yes, we have a lot of blackouts). Bottom pads on my keyboard are made of TPU. I consider that revolved parts are able to be printed with simple bowden printer and are effectivelly usable in casual home works as a parts with different properties in comparison to common materials

[@bastianenis6412]

I never put glue stick on my print beds. Just make sure you have a properly levelled build surface. I usually print TPU on my smooth PET surface and I cannot complain about too weak or too strong bed adhesion. Same applies to my Ender 2 with stock surface and bowden setup. I lowered the print speeds drastically on the ender, btw.

[@karsvau453]

Ok but others do different.

[@tylerstank2714]

I bought a spool of TPU quite a while ago and I think I’ve only used it for two things - dampers for the brake pedal in my sim racing controls to make it feel more realistic than the spring it came with (which worked perfectly) and a vibration isolating mount for the accelerometer in my race car. I’m not sure how well the latter works as I’ve never tested the accelerometer without it, but it seems to be working well. I also have a 3D-printed housing for a display in the car that I’ll eventually be making some gaskets for as the components themselves are not waterproof.

[@daysejones968]

can you make a video about how safe those reinforced materials are to your health? small glass/carbon fibers can be dangerous

[@ryanb9749]

I'm thinking about trying iron powder. Iron is naturally in your blood so it's probably not that bad...

[@kirahund6711]

The materials aren't dangerous to you since the fibers are embedded in the plastic and will not magically leave it unless you burn the plastic away. How safe these fibers are depends on the diameter of the fibers. I don't know about other countries, but here in Europe most commodity plastic manufacturers have switched to fiber diameters that are considered harmless for workplace safety reasons.

[@cho4d]

flesh colours soft fillament? na i can't think of anything to print with it either 🙄🙄

[@crowguy506]

Na, but you might have to add some blue to increase shore hardness on those.

[@becauseican2607]

Would expect the counterpart oft what he prints in the background but hey... No judging😂

[@tarakivu8861]

Please dont print stuff like that and use it.. there are a ton of chemicals in there you def. dont want your body to take in.. If you really want to get into it, buy some Platinum grade Silicone (quite expensive), mold seperation spray (wax based should be fine) and 3d print your mold, maybe something like PBT to smooth it. You want it smooth, so nothing grows in the fine spaces between the print lines. For coloring, you can use Cosmetic grade mica powder, make sure its fine enough so it doesnt cut itself out of the silicone.

[@bubblinebee]

@@tarakivu8861 Not just chemicals, there's no way a porous-by-nature 3D print is going to stay clean.

[@PiDsPagePrototypes]

That material mike be idea for printing 'skins' for prosthetic limbs like the Hero Arms. Then get them painted with details to match the wearers skin tone and freckles and the like. It should also be easy to use to make the base shapes for film and TV effects make up pieces, such as Elf/Vulcan ears, Hellboy horn stubs or Twi'lek Lekku for CosPlay, or tentacles for live action Anime.

[@benjikrafter]

For flexibles, I have so many tiny spots where filaments can grab. So, I have to decrease the retraction distance, but usually increase the retract speed to get it out of the way fast. And otherwise avoid retractions when possible.

[@SheriffJackCarter]

When I print in TPU, I use a Garolite FR4 print surface. The piece holds down well enough with very little peeling, but comes off cleanly with relatively little force. So far, the most useful thing I've made is a set of custom-designed plates that are used in a factory in Michigan on a machine that does plastic-injection molding. The plates hold reels of metal pins that weigh about 46kg each and are mounted on a machine that slowly un-spools the pins from the reel on demand. The reels themselves are made of cardboard with a thick cardboard core. The plates add pressure and increase the holding surface area to keep them centered and keep them from wobbling and being damaged during unspooling. In addition, if the cardboard spool is damaged, then the cardboard center can be cut out with a knife and the plates can be inserted into the hard cardboard core of the spool allowing the reel to be unloaded normally by the machine. So why did I print them in TPU? Well, PLA definitely does the job better when it comes to compression, but does not do well at all when it comes to impact. But I hear you ask, "If they're just holding cardboard spools on a machine, where does the impact factor it?" Glad you asked. It comes down to 1 word. 'People'. When the spools need to be changed, the plates are removed and people are rather careless, so the plates ended up falling or being tossed on the ground and PLA will shatter. Making the plates out of TPU allowed the plates to withstand the abuse of careless operators while maintaining the rigidity necessary to keep the machine operating properly and more reliably.

[@tyrathect2471]

I love printing print in place flexible things like those wiggly dragons out of TPU. Super shiny and nearly indestructible for kids.

[@tinathecrafter]

As always your videos are so thorough!

[@MajikPPMan]

Stefan, can you please do a video specifically talking about supports for TPE filaments? I think alot of makers use it less because of how difficult it can be to remove them without damaging the part OR how to remove them without leaving the part ugly. Thanks!

[@saltwaterrook4638]

My volumetric flow for Ninja Flex (85a) is 6mm/s³. That's with an extruder and hotend combo I designed specifically for TPU on a highly modified Ender 3V2. It's my printer for flexibles while my Vorons and Bambu do everything else. As for bed adhesion, no glue or anything on a textured surface and I have no issues. The trick, set your end Gcode to set you bed temp for 80c. Having the bed heated up significantly increases the ease of getting TPU prints off the bed.

[@uhu4677]

Indeed. Textured PEI. Printing cold. Heating for removal. Works great. Still be careful and don't rip it off with too much force.

[@kozmaz87]

Well idealized/simplified physics about friction always start with the declaration: for rigid bodies and smooth surfaces. That is why your "anomalies" showed up. For flexible materials friction coefficients are not static. Think of temperatures affecting tyres or how their deformation changes how much friction they have. Try a much heavier weight and you should be getting higher friction coefficient.

[@vogtm]

BTW: I have tried printing Varioshore TPU on the BambuLab X1C. It causing no problems until it starts to foam up. When it foams, i had clogged nozzle many times. I think it would require to adjust the Z-axis (first Layer) manually, which isn’t possible as I,m aware of. On the Prusa, this works better (even on a Prusa Mini).

[@rudimentaryganglia]

The standard easy setting for TPU on my ankermake m5c gets me pretty much perfect prints with minimal stringing every time.Only stringing issues with the last print I did was because of moisture pickup,the first print I did with it in a long time and the supports even came out quite easily at around 10 percent density

[@licensetodrive9930]

Fascinating video! TPU is my favourite filament to design for, like my Hoopin TPU Cable Tie, I use them everywhere, even carrying handles for drinks bottles. Going to have to get some TPE now to see what it can do and see what I can make with it.

[@sidewinderam9m]

I built a heated chamber around my super cheap printer. The spool holder is in the chamber. I usually set the temp to the drying temp of the filament as that is usually a good temp to prevent warping. Then I just store the filament in desiccant box. Never have to worry about drying. Just used some cheap parts like a heat gun and some purple foam from HD for the chamber. Put the electronics outside the chamber....flexibles are probably my favorite filaments because the layers bond so well And I never have to worry about the part breaking.

[@Zack-dw5op]

Is there a reason you linked the sunlu S1 over the S2? Is it better then the S2?

[@richdobbs6595]

I've used TPU with a Creality CR6 SE to print replacement lids for Corning Ware food storage. It worked okay. Hand wash only. I just used the default settings and it seemed to work fine with a PEI surface. In this role, it is not in direct contact with the food, so I just lived wild and crazy!

[@markusrichert5441]

Hi there. Your Setup for the friction test does not work for flexible materials. In addition to the force to overcome the friction, you will use a part of your measured force to elongate the flex material, so your measured force will include friction and elongation (yo can already see the deformation with the softer stuff in your video). That would also explain your abnormal behavior with the greater sliding friction. A better setup would be a simple ramp with adjustable slope. Put your material with some weight on the ramp and increase the slope until it starts moving. From the slope you can calculate your friction coefficient. At least the static friction coefficient should be measurable with this.

[@TheRawketLawnchair]

@4:28 i see what your printing there. lol nice joke

[@cdavisrun]

I had to back up when I saw it. He little mermaided his video

[@HerbaMachina]

10:50 honestly you can easily get up to 15mm^3/s fairly easily with tuning if your printing 95A TPU. And you can print at 30mm/s print speed no problem on the flashforge creator pro 2, and I imagine any printer similar to it. Everyone gives incredibly conservative print speeds it seems for TPU. The main killer is to turn off filament retraction

[@timfairfield407]

I was amazed at how strong it is. I had chairs with pointy feet that were gouging my floor. I printed custom feet that fit like a glove and they are super strong I used bowden not direct drive and I only have to be careful during the filament loading stage to go really slow to feed it in otherwise it squeezes out the bowden drive. But I made some slow gcode just for TPU loading. Great analysis here. I forgot about the glue stick at first and wow it really adheres to the bed. Do not forget the glue stick.

[@ampex189]

Perfect timing for this video! I just got my first 2 direct drive printers yesterday!

[@alonalgr660]

Thanks for the info! Would have appreciated checking temp resistance as well