First TPU Print  

RE: First TPU Print

I think the most important thing is to lower the "Max Volumetric Speed" setting in the slicer down to around 3-3.5 mm3/s.  The other thing you might need to do is loosen the  idler arm adjustment screws a bit to set the tension right on the extruder gear.  I didn't have to do the this when I started printing TPU, but others here have.

Keep In mind that TPU sticks hard, so release agent on the build plate is recommended, especially if you are using the smooth PEI sheet.  I've actually been printing on Garolite, and I have turned the bed heat entirely off  for TPU and it sticks well and releases fine on a bare plate, but I understand that most people are using OEM build sheets.

TPU has been painless for me from the start, with no clogging and nice prints.  You do need to work harder to keep TPU dry though, and it might be a good idea to dry it for before printing to be sure it hasn't pulled in moisture.

-J

RE: First TPU Print

Thank you!   I'll dry the TPU overnight, then try a Benchy with it.  

I'll keep in mind your suggestions re print speed and tension screw.  

I'll report back tomorrow with results.

(we noobies have such basic questions, but they seem insurmountable to us)

RE: First TPU Print

I'm also a relative newbie, but so far printing has been easy on this thing, with almost no failed print waste.

-J

If you buy a TPU listed in the filament dropdown you won't have to juggle settings as the Mk3 presets are very reliable 'though a bit conservative.

You *must* slacken the extruder idler - it needs to be the minimum pressure that just grips the filament, you may have to experiment the first time you try TPU, if it is even 

a fraction too tight the filament will tangle around the Bondtech gears and jam.

And as @teamd3dp suggests, dry your filament, really dry your filament, always dry just before printing.

Use a release agent or you risk damaging your print sheet.

Cheerio,

RE: First TPU Print

Do I need to use a release agent if I use a Textured Powder Coated steel sheet?   The official one from Prusa?  The one I have is a TL-21

RE: First TPU Print

I don't have a textured sheet, so I'll let someone else answer.

-J

RE: First TPU Print

I print TPU on a satin sheet using 3Dlac as adhesive/release agent.  It's not strictly necesssary with satin or textured plates, but it helps to remove the prints without leaving very small particles of sticky filament embossed in the crevices of the plate.

TPU comes in vastly different hardness grading,  Relatively hard TPUs ( shore 95-98A ) aren't so difficult to print but very soft ones ( shore 70A or less ) are another story, 

RE: First TPU Print

I can't experiment with TPU till later this week.   I'll update y'all when I do.

Thanks to all!

Do I need to use a release agent if I use a Textured Powder Coated steel sheet? The official one from Prusa? The one I have is a TL-21

I have never printed TPU on that particular sheet, you might get away without but I would expect to use a seperator just a light spritz of window cleaner or diluted PVA/gluestick.

Cheerio,

RE:

Successful TPU prints!  

I used Overture High Flow black TPU.   I made no changes to the standard Filatech TPU profile in PrusaSlicer.   But I did loosen the Idler screw a bit.  

I had no problems with the filament feeding the nozzle, although the cardboard Overture spool has too much resistance against the standard Prusa spool holder.   I'll need to make some ball bearing holder.

I made supports in CAD, as I didn't know about the Organic Supports in PrusaSlicer.   I'll know better next time.   There's some stringing, but the part is good enough
to use.  It's a turn signal stem for my motorcycle.  Oh, that quarter moon thing was my first attempt at a TPU print;  it did ok

Edit:  I used the Prusa Textured Powder Coated sheet without any release agent.   Yes, the prints stuck well, but they came off ok.

Thanks to all for your help!

RE: First TPU Print

TPU is flexible and can be tricky to push through the extruder without jamming. Start with a print speed around 15-30 mm/s to ensure good filament flow.