Warping Issues with PA6-GF Filament

[user_269543255]

Dear Team,

I’m experiencing severe warping issues with Bambulab’s PA6-GF filament, regardless of the settings used.

Setup:

Printer: P1S with AMS, 2 weeks old, fully calibrated, factory settings.

Room temperature: 21°C.

Plates: Textured and Smooth Plate from Bambulab, using adhesive (3D-Lac spray).

Nozzle: 0.4 mm hardened steel.

Extruder gears: Currently stainless steel, with a hardened steel set available but not yet installed.

Slicer: Bambu Studio, latest version.

Settings: Using AMS system with the automatically detected filament profile for PA6-GF. Speed reduced (≤100 mm/s), bed temperature 100°C. Cooling fans set to a maximum of 10%, as defined in the profile, and I have confirmed the fans are working properly.

Infill: Tested with 10% (reduced) and 15% (default) using Gyroid and standard infill patterns.

Filament preparation: Dried in a filament dryer for 9 hours at 65°C before use.

Problem:
The model warps severely, especially at the corners and across the surface, regardless of the print size. For example, the Benchy detached from the plate mid-print and fell off, with the filament continuing to extrude into the air (see attached photo). My nearly new print plates, including an unused Smooth Plate, offered no adhesion even with glue.

Despite 4–5 attempts using different settings, the issue persists. Other materials like PLA, ABS, and ASA print flawlessly under the same conditions, leading me to suspect a problem with the filament itself.

I would appreciate your assistance.

Best regards,
Patrick

[EnoTheThracian]

I think those 9h @65°C drying may be rather low for PA6.
https://wiki.bambulab.com/en/filament-acc/filament/dry-filament
I just did some very nice PA6-CF (which admitedly is better at warping than GF due to heat distribution during printing) prints, but dryed for 60h at 60°C.

[user_269543255]

Thanks! might be the problem and I’ll give it a dry :). The filament was new, fresh from the package right into the dryer. You think it comes “unusable” from factory?

[EnoTheThracian]

That is at least the one safe assumption. In particular since PA6 is quite hygroscopic.

[user_269543255]

Alright, filament is back in the dryer. I’ll try my print in 3days again. Let’s see…and find out

[EnoTheThracian]

Just for when the filament is ready:

• I have found the smooth PEI with glue giving much better adhesion than the textured plate.
• A brim can also help. Just like improved adhesion, it treats the symptons rather than the root cause.
• If in dire straits, you can also try to reduce the layer height (except layer #1) for the first 2-5cm height. That will give a more even part cooling. It works through targeting the root cause.
• Print with as warm a chamber as possible. You can use a heat soak ahead of printing and be carefully creative about printer isolation. My build chamber was at 49° for most of the print. Used my cardie for added insulation (top, front and sides only) to get to 51°C. Also helped when going for a smoke in the snow

[user_269543255]

I apologize for the delay in responding. Over the past few days, I have conducted multiple tests and tried various solutions to address the issues with PA6-GF filament adhesion and warping. Below is a summary of the steps I’ve taken. It still doesn’t work :

1. Filament Drying

   • I dried the PA6-GF filament in a filament dryer for 56 hours to ensure its dry.

2. Temperature Monitoring

   • I installed a thermometer to monitor and stabilize the ambient temperature inside the print chamber.
   • It was always between 50 - 65 celcius in the chamber when printed.
   • I also preheated the chamber 1 hour before

3. Glue

   • I used multiple 3d printing glues:
     • 3D Milk: A plant-based adhesive.
     • 3DLac: A adhesion spray
     • but no glue Stick so far (may this is the issue)

4. Printing Tests

   • I printed a Benchy test model from Bambu support team provided with 16mm layer height and some slight improvements (lower speed, infill, etc.)
     • It took 4 attemps to achieve a successful print:
     • On the fourth attempt, the model adhered slightly better to the build plate so it could finish the print but still showed some warping.
     • The print quality was otherwise excellent.
   • I suspect the failures in the first three attempts were due to insufficient adhesion and the significant warping of PA6-GF.

5. Build Plate Tests (always with glue applied)

   • I used the following surfaces:
     • Bambu Smooth Plate: Used for all tests; minimal adhesion.
     • BigTreeTech PET Carbon Plate: No adhesion at all.

6. Comparison with PETG HF Filament and ABS from Bambu

   • Using PETG HF + ABS by Bambu, I encountered no adhesion issues. The prints sticked strongly with the same glue.
   • The adhesion issues are specific to the PA6-GF filament.

7. Next Steps

   • I have ordered an additional glue stick for PA to test if it improves adhesion further.

Despite these efforts, it is still surprising how strongly the material warps and how poorly it adheres to the build plate compared to other materials.

Is this normal? Or may it has some defects in the material?

I have attached images of the test prints and setups for your reference.

Thank you for your continued support. I look forward to your recommendations.

Best regards,
Patrick

[EnoTheThracian]

Well, I have had very good experiences with the PA6-CF. And that is probably the big difference. The Carbon helps to distribute the heat more evenly in the part during printing, greatly reducing warping.
Would CF an option for your project? Or do you need GF?

Because other than that, it looks like your only remaining options are the addition of brims with a 0mm gap, thinly distributed Dissolved PVA glue stick with a freshly cleaned plate (dishwashing liquid and water), using an even finer layer height (0.08mm) as well as printing even slower. Unfortunately, I can not give you a “this will work”. It should improve somewhat, but PA6-GF seems to be a different beast from PA6-CF.

[user_269543255]

Thanks a lot! I’ll try the other glue and let’s see.

I can also switch to the ca version. No probs. I’ve just bought the gf for convenience as it can be printed from the AMS.

I am just a bit disappointed that it doesn’t work so easy and at this price point so warping. But let’s see what the glue stick brings!

Overall the material is really nice when it stays in place.

I’ll keep you updated.