Tips for TPU?

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I just did my very first TPU print after years of printing PLA and PETG, and I've gotta say: That stuff sticks like a mofo on the textured PEI plate..!!
The print turned out great and the default profile in BS needed very little tweaking.
I'm currently using Fiberology MattFlex 40D.

What do you guys use to ease the removal?
I've seen normal glue sticks, IPA and liquid glue made for 3D printing, but I figured it would be cool to ask the fine people here.

If you do use glue: Do you stick with a smooth PEI or maybe something else?

All feedback is appreciated!

Thanks in advance!

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I've had success printing TPU onto the uncoated steel side of a print bed. Flip it over and clean it, gently sand it if it's too smooth for the first layer to grip.

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I'll write this behind my ear for the next plate purchase! Thanks

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I just use my textured sheet and remove very carefully - but I tend to use harder TPUs which makes flexing the sheet more effective.

I have heard people say that TPU is the reason they still keep a glue stick handy and the Prusa material matrix says to use it on their smooth PEI sheet. And it suggests a polypropylene sheet is also applicable without glue stick.

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Smooth prusa powder coated works great.

Drying makes a gigantic difference. It only takes around an hour in the open before TPU changes significantly from any ambient moisture and become visible in the print.

If you can control the moisture to a minor degree, you can alter the mechanical properties significantly. Once you hear popping, you'll likely start blowing holes in prints, but there is a stage before this where the bubbles of gases are present but are not coalescing into the larger audible voids of escaping steam. You will see this on long prints using dried TPU filament left out in the open. There will be a much tougher start to the print that gradually degrades into a slightly softer and more flexible texture. It will likely turn slightly foam-like spongy rubbery soft for a section and then it will start popping and dropping walls with holes in the structure.

If you write down the room temperature and humidity and note the time it takes to get to this moisture property, it becomes possible to alter the flexible properties or empirical hardness of a TPU to make it behave in off label ways. This is essentially creating your own rudimentary foaming or light weight filament. It works best for vase mode or other small single wall structures. I have used this based on intuition alone. I imagine with a bit of record keeping one could control the humidity of a box to do longer prints within this state of foaming softness. I don't know of anyone using a humidifier like the ones for acoustic guitar cases or cigars in a filament box, but that would be an interesting thing to play with too.

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Not sure if I've ever tried without it, but I cover the standard textured mat with blue painter tape for printing 95A TPU on an Ender 3 Pro. It sticks just fine for printing and haven't had any issues removing the print after.

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I've seen some people do this!
Any reason you opt for this over a stick? Seems like a lot more work

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Could be interesting to play with in the future, once my confidence level on the material rises a bit.
Thanks for the tip!

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This is the first time I've had this much issue removing a print.
I knew it would stick fairly well on the textured PEI, but this was a whole new level. A bit surprised I didn't peel it, to be honest.

I'm leaning the same direction as those people: Buying a stick and keeping it around for those few times I do use TPU. PETG and PLA is still 98% of what I print, and they both come off easily on textured and PLA easily on smooth.

The question I'm stuck with though: Textured with glue or smooth with glue for TPU?

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When I first got the printer and was learning I used glue sticks to help with adhesion and just got sick of dealing with the residue and reapplying it - so now I intend on never using them at all if possible. I have 2 of the printers, one just for PLA and has a smooth PEI sheet, the other for PETG/TPU and just the regular textured mat that came with it. I usually don't need to swap between filament types a bunch so when I've got some prints that need TPU it only takes a couple minutes to apply the tape and then I can just leave it on for as long as I want and not think about it. I also use the wide blue tape (can't remember if it's 2.5 or 3") so it's only a couple rows to put on.

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I used to throw the textured pei plate with the sticking print into the freezer for 15 min, made removal much easier. Now I just add baby powder onto my build plate, and remove the print at room temp. Much easier, a little messier

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I've read that PEI makes TPU much more difficult, and switched out my PEI plate to my plain glass plate because of the horror stories. I just rattled off some TPU last night using glass and a single pass of a PVA glue stick, and it was super easy to get on and off the plate. Like if PETG was a bit stickier.

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I suspect that cleaning the glue off the textured sheets is a bigger pain in the butt than off the smooth. But I say that as someone who never tried to clean PVA off of PEI.

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Wait what?

The freezer trick I've heard of, but baby powder?
Applied before printing then, I guess?

My printer is enclosed and I'd wory about the aux fan blowing it everywhere.
Even with 0% fan for first layer, I'd never be able to perfectly distribute it under only the print...

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I see many use glass still. Old school way of doing it, but if it works then I guess it's good!

I'm mostly leaning towards smooth PEI with glue for my next print. Hopefully that will be better than textured with no release agent. Fingers crossed and thanks for the feedback!

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Cheers mate! Much appreciated

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I've got a textured PEI bed and when I've printed TPU, the adhesion has been perfect, i.e. good enough that the part wasn't going to go anywhere unless I wanted it to, but still easy enough to remove when the print was done and the bed had cooled. I guess it could vary from filament brand to brand, so it's possibly worth trying the same brand as I used, which was cheap Geeetech stuff. It's £8 a roll, and I've used their cheap PLA for ages. I wouldn't recommend their ABS+, though, as it seems to break down at the lowest temperature that gives reasonable layer adhesion.

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I've never had too much trouble removing TPU from a textured PEI plate. If the part doesn't want to come off, lift up a corner of the part with a knife and put a drop of IPA under it.

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Apply baby powder on the build plate, shake of the excess. Seems to fill in the gaps. I can't recall where i learnt about it, but it works really well. Stickiness on textured pei is comparable to pla or petg.

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I use a bit of glue and try to remove it when it's still warm but not hot.
Zero issues so far.

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Tips for TPU?