Printing foaming TPU (Filaflex Foamy) - my first experiences

[matthiasdeblaiser]

After playing around with Fiberlogy’s 40D and 30D, I wanted to go even softer and got myself some Recreus Filaflex Foamy.

As a test I chose CNC Kitchen’s corner bumper as it’s quite ideal for a softer print.
https://www.printables.com/model/369017-corner-bumper-tpu-optimized

My first print:
Printed from Sunlu S2 filament dryer
250°C
0,2mm layers
30mm/s
flow 65%

The print finished, but had severe underextrusion with some layers having almost no extrusion at some, causing the print to separate easily at those layers

The second print:
Printed from Sunlu S2 filament dryer
255°C
0,2mmm layers
20mm/s
flow 70%

The print finished, but had more or less the same problems. Consistent underextrusion was down but only a little. The intermittant lack of extrusion however was even greater

The third print:
Printed straight from the roll to extruder (roll suspended above printer) without any PTFE tube
250°C
0,2mm layers
flow 70%
30mm/s

This one I stopped after a few layers because I could already see the walls not touching

The fourth print:
Same as previous but at 85% flow

To me that one is spot on. The layers without any extrusion are gone and probably caused by the filament gripping inside all of the PTFE tubing from my filament dryer all the way to the extruder

So 85% flow is the way to go but that’s a long way from the prescribed 60 to 70%

Seems like the X1’s extruder is squishing the filament, giving an me a way lower flow rate. The weight of the part at 85% flow should be 6,8g according to the slicer whereas I measure 5,9g. Assuming the bubbles in the filament do not contribute anything relevant to the total weight, the Filaflex foamy filament is extruded at about 87% flow compared to harder filaments.
I would not have expected this because my flow rate multiplier for the Fiberlogy Fiberflex 30D is 1,03 and yet its about the same squishyness as the Foamy filament in its filament form

I hope this finds it’s way to people who want to try this foamy filament on their Bambulab printers because I could not find any decent real experiences

[mx.ourada]

Have you attempted to adjust your idler spring? I’m planning on adjusting mine soon to test it, as I was getting a lot of under-extrusion and straight up slipping of my gears. My first successful print was at 1.1 multiplier, but I really want to get that down to at least 0.8

[SimEyeSee]

Bambu recommends using only the harder TPUs because of the exact problems you are having. They speak about it here.

TPU printing guide

[SinWolf]

Good day,

I want to try and print Fiberlogy 30D. Are you willing to share your tips/tricks and settings? I have successfully printed 95A, but this is the easy stuff… I need to print something softer.

I can’t seem to find any info on the net with regards to 30D TPU on a Bambu Lab Carbon X1.

Is it possible and fairly straight forward and reliable? Or will this include a lot of tinkering with the printer hardware?

Any and all info/advise will be much appreciated. Thanks

Thanks

[beerdart]

30D is about the same as 80A.

[A_2]

amazing!! these settings worked PERFECTLY for my X1C first try I got an amazing foam print. Crazy this stuff really is just like foam. I had to build a little custom rig to get the roll centered over the machine but its crazy how great it worked. thanks for posting!!

[ehrichey]

Hello! Also trying to work with Filaflex foamy on an X1. What did you use for your retraction settings?

[T_guttata]

Interesting material. I’m looking for a soft TPU to do a customized eye cup for a camera. Do you think that mtaterial would be suitable to do so?

[Ken-N-Texas]

VarioShore TPU is a foaming filament. I’ve printed that at Shore-A 59-60. The hardness (or softness) varies with the nozzle temperature. It took some adjusting but works great and it’s soft. However, it is slow printing. I haven’t tinkered with the settings to get the speed up as most of the stuff I’ve printed is small–Like lens caps.

These were my settings. Not shown is the retraction setting of 0.4mm.

These were a couple of caps I printed. They measure about 56mm across.

[user_3026326371]

I noticed that there is a relationship between speed, temperature and flow rate.
Problem with our extruders is that a quite resisting hotend follows.
Printing extra wide in vase mode gives rather stunning results once the parameters are honed in.
For anything else it is a balance act as not even the usual calibration routines work consistently enough.
I have to say though things do work a better using my E3D.

I think the issues comes with the foaming and our hardware.
Ideally the TPU would foam outside the hotened, once it got through the nozzle.
While normal TPU can tolerate retractions the foaming kind seems to start foaming once the pressure in the melting chamber gets too low.
This results in the volume expanding, which in return brings inconsistencies.
Avoiding those and trying to keep even speeds and flow rates seems to get the best results.
It is a bit like with the foaming PLA…

For many models you can get away without retraction, especially is printing slow anyway.
The high travel speeds we are capable of mean there is little time to ooze.
I guess we should focus more on creating soft TPU friendly models

[Ken-N-Texas]

I just haven’t had time to play with settings and hot ends. I used my go-to 0.4mm tip and 0.20 layers. I was getting way under extrusions until slowing the flow and speed. I’ve got the 0.6 and 0.8 hot ends but like the detail the smaller tips produce.

When I bought the VeriShore, they sent along some samples of what’s supposed to be Shore-A 40 filament. I’d like to try that but don’t want to waste it. It’s like maybe 30-40g–Not a lot to play with. All the specialty filaments are pretty pricey for an old, retired guy.

I have Shore-A and D testers with a stand and weights. It’s pretty simple to set up and test hardness of samples. The issue is producing a sample for a valid test. The wall thickness and fill play a huge roll in the “feel” of the finished model’s softness.

[rico3Dmaker]

@matthiasdeblaiser could you share the profile of this print with me? Thanks