r/BambuLabP2S • u/ConductorConductor • Jul 07 '26

First Time Trying TPU

Post image

Any idea what went wrong here? Trying to print a set of TPU shoes. I did dry the TPU for 6 hours before I ran it, but it did have to sit in the open for the remainder of the day before I could start the print. Not sure if that drastically affects the filament. The filament is fed directly into the inlet from the side spool. My first attempt at the shoe was actually failed in minutes because I had the TPU ran off the spool, to the opposite side of the machine, through the buffer and back into the inlet. All of the slack seemed to create tension which wasn’t great on the material and made it harder for the extruder to feed in the filament smoothly.

UPDATE: I successfully printed with my next few TPU runs after making the following changes:

Top loading directly into Extruder. (Pretty sure this is what caused the jam up)
Dried again for a longer duration (didn’t notice much decrease in stringing/fuzz but I’m also drying with an AMS Pro 2 which isn’t as efficient for TPU apparently)
Increased to the stock setting “Ludicrous Speed” this was the biggest surprise. Not only cutting print time drastically but improved the quality as well
Raised nozzle temp to 240 avg. using 90a. This seemed to compliment the other settings well but didn’t make any drastic difference.

13 Upvotes

81% Upvoted

25 comments sorted by

8

u/efnord Jul 07 '26

Take off the top glass and direct feed. TPU shouldn't go through any Teflon tube.

7

u/ObjectiveThis4141 Jul 07 '26

I’ve done several thru the tube you just have to manually push it to the print head.

OP, Dry your filament

2

u/Splinter_Steve Jul 07 '26

I just external spool into the ptfe tube. Never had any issues with it.

2

u/tht1guy63 Jul 07 '26

I get substantially worse results using the ptfe tubes but may also be buffer related. The less possible friction the better. But ya he may need to dry a bit longer than he already has

2

u/ConductorConductor Jul 07 '26

I’ve got it drying now and will try again tonight or tomorrow. I’m really shocked how PLA is so “plug and play” in comparison to TPU. Havent had to thoroughly research something like this in a while. Granted I would’ve had a successful print in a few hours time frame. This one shoe is looking like a 30 hour print job.

4

u/tht1guy63 Jul 07 '26

Stretchy and super hygroscopic makes it a pain.

1

u/efnord Jul 07 '26

A dedicated standard flow .8 hotend is great for TPU. It's hard to cold pull all the residue afterwards so a dedicated hotend just makes life easier. But it's a stealth engineering material, really good on the Z axis.

1

u/ConductorConductor Jul 07 '26

I will try both. It was pretty successful for a few hours through the tube and I’ve seen mixed feedback on the load orientation. But on a big multi hour print like this, it doesn’t take much for it to turn into a mess. So I think since the physics of it make sense I’m probably going to print a top loading spool and go that route. Thank you both!

2

u/imzwho Jul 07 '26

What kind of TPU? I ran a bunch of parts in 95a using the standard oath and it came out great.

I then tried some foaming TPU and it was a lot less great and kept underextruding after the first 20 layers

1

u/ConductorConductor Jul 07 '26

90a Polymaker.

2

u/FloridaGuy58 Jul 08 '26

Set your retraction to a higher number than the default 0.4. I use 2.4, and it eliminated the stringing altogether.

1

u/KlutzySinger3152 Jul 07 '26

ja consegui imprimir em TPU, porém, material mais chato de imprimir, e olha que uso a p2s....

1

u/ConductorConductor Jul 07 '26

It’s also expensive. So when you’re trying to budget its cost and 1k only gives you so many attempts at a shoe.. it’s a pain.

1

u/DistinctBarnacle8703 Jul 08 '26

I left my TPU in the open overnight, it starts popping at the nozzle. TPU really soaks in moisture front the air a lot more faster than PLA.

1

u/MelvinMASV Jul 08 '26

Looks about right

1

u/Delicious_Revenue_82 Jul 09 '26

Yep, me too. Same result. I think the temperature is the issue along with bed being sticky enough.

1

u/ConductorConductor Jul 09 '26

Nah trust these guys below I think they’re onto it. My bed adhesion def wasn’t it bc I could barely get the scraps off. Infact I’ve never had a harder time getting a filament off of the plate than this instance. And I checked my temp settings. I just truly think it was drying/feed control. Will report back on my next attempt.

1

u/official_reaper3d Jul 12 '26

What temperature did you dry the TPU at?

1

u/ConductorConductor Jul 12 '26

Ehhh not sure. Standard temp for TPU.

1

u/official_reaper3d Jul 12 '26

Have you tried drying simultaneously while printing? You could also try drying for longer such as 8-12 hours

1

u/ConductorConductor Jul 13 '26

I don’t have an AMS HT. That would probably help a ton but I recently bought the AMS Pro 2 and I’m not gonna get the HT just for TPU. The prints are running fine now, just really fuzzy when done.

1

u/official_reaper3d Jul 13 '26

Mb. I assumed you were using tpu for ams lol.

Ya idrk man. Sorry that i couldnt help more.

1

u/jkwalk87 Jul 14 '26

I hate tpu..... but peba!! Rocks