Print Transparent - outer wall change from smooth to rough and back

Bambu Lab P Series Troubleshooting
1

Hello forum,

I’ve been successfully printing with my Bambu P1S for four months now.

I recently decided to try printing with transparent PLA. I used the manufacturer’s recommended settings for transparent printing and haven’t changed anything else:
Printing tips for transparent PLA/PETG | Bambu Lab Wiki (Fan off; Flow rate 1.01; 230°C (max for the filament); Layer height: 0.1mm; Line width 0.5mm for everything, 1 wall line, 100% infill, speed for everything 20mm/s).

Problems:
(1)
At a certain height, the outer and inner walls suddenly become rough and textured. Then they become smooth again, and later, they turn rough again. (See attached image).

(2)
The two lower tips print well, but the last tip at the top does not. I suspect it’s getting too hot because the fans are deactivated. But i cant find an option to turn on the fan only for the highest smallest point.

The day before this transparent print, I had perfect results with black eSun+ and a 0.2mm nozzle (using the slicer’s standard settings and without the changes described above).

Details:

Filament: iSANMATE Transparent High Speed PLA

Printer: Bambu P1S

Slicer: Bambu Studio 2.1.1

Print File: See attachment

Nozzle: 0.4mm stainless steel

Bed: Bambu Cool Plate SuperTack

I would be very grateful if someone has a tip on what I could try!

Screenshot 2025-07-20 173040
Screenshot 2025-07-20 1730401863×672 333 KB

2

Firstly, I welcome you including a great summation of your details.

Your photo shows me something is different, but without sufficient quality that I can see what the difference is.

Personally, I hate the SuperTak plates, if they work for you, great. I have 5, all five are bad.

PLA Translucent materials are rare and some think new. I have been using them for some time.

There are things you must do differently if you wish to benefit from the translucent effect or you will have problems at worst, opaque at best.

I published this well over a year ago, neither filament used is from Bambu Lab.

The keys to usage is control of speed, your filament says high speed, that is not conducive to a translucency outcome.

Other factors require a smooth plate, matching directions of printing, little infill and few walls.

With a better picture I might have more to share.

The o e common issue though for all filaments is moisture content, it can throw off all filament quality.

I saw this despite having only dried two spools and owning a combination of 5 bays for drying (more money than sense?)

Filament from the factory can and does contain moisture. This is not true from all factory ps, all filaments and in all countries. But, it does happen, happens a lot, and is often the cause or errant results.

3

Transparent PLA can be tricky because it needs different cooling compared to opaque colors. The rough/smooth banding usually comes from heat buildup and inconsistent cooling. You can try lowering the temp slightly (225–228°C), enable at least a little part cooling (20–30%) for small tips, and reduce flow back closer to 1.00. Also, printing with more walls (2–3) instead of just one will help give more consistency and clarity. For the very top tip, a ‘minimum layer time’ setting or slowing down the print speed helps the layers cool before the next one goes on.