Flow Dynamics and Rate Calibration Questions

[muzicman82]

OK, I’ve read a few posts and Wiki on the two calibrations that are found in Studio. If I missed these points, I apologize.

• I’m primarily using only Bambu PLA Basic filaments. Will performing these calibrations fine tune settings further than the default settings/profiles?
• My understanding is that these calibrations can vary between even different colors of the same filament, so is it best to do it for every spool or every SKU? Are these dialed in for the printer or is it a combination of the printer, filament, age on nozzle, etc?
• What is the printer’s built-in calibration procedure calibrating?

[Olias]

Welcome to the community.

The calibration utilities allow you to take very specific steps to fine tune the parameters that control how filament is extruded, and indirectly how the nozzle moves. Any filament profile you tune is saved under a new file name. The system does not allow overwriting the default profiles, so there is no risk of breaking anything permanently.

Filament tuning is part science and part art, and it is influenced by many variables. You already noted batch and color variation within the same manufacturer. Moisture content, ambient temperature, and nozzle wear also matter. In most cases, these factors will not prevent an acceptable print, but if your goal is the best possible surface finish and dimensional consistency, tuning is the correct process.

As for why to bother, my motivation was maximizing my filament budget. The default Bambu profiles are close, but they leave performance on the table. Once you understand and use calibration properly, you are no longer locked into a single vendor’s filament ecosystem. A well tuned third-party spool can perform as well as, or better than, a Bambu branded spool, provided the material itself is decent. Calibration is what makes that flexibility possible.

[muzicman82]

This is great info… but to the last point - is it worth taking the time to learn and do this on Bambu PLA spools or are their own defaults and profiles “close enough”? I haven’t had much reason to question them… but, if done, will I even notice a difference? As in – Can a Bambu branded spool perform better than OOTB?

I guess I want to hear from folks that regularly take the time to calibrate and find that prints are “better”. I know it couldn’t hurt to try… but I also wonder how using my own calibrated settings will affect the outcome of downloaded projects on Maker World designed with defaults.

[Olias]

@muzicman82

I guess I want to hear from folks that regularly take the time to calibrate and find that prints are “better”.

You can count me as one of those people, for better or worse.

@muzicman82

Is it worth taking the time to learn and do this on Bambu PLA spools or are their own defaults and profiles “close enough”?

Short answer: for PLA, the defaults are usually close enough.

Speaking as someone who leans toward perfectionism, if you are using PLA - whether Bambu or generic - most stock profiles will produce results that are already very good. The full answer is subjective, because many people who are new to printing have not yet developed a clear sense of what a “perfect” print looks like versus one that is merely “good enough.”

Proper calibration can easily take over an hour, and if you go deep enough, it is possible to spend most of a day tuning a single filament. That time can be valuable as a learning exercise, but only you can decide whether the return is worth it for your use case.

In practice, two factors have a much larger impact on print quality than fine calibration:

• A clean build plate
• Dry filament

PLA is relatively forgiving, but even PLA can suffer from moisture issues or the occasional bad batch. Materials like PETG and PC are far more sensitive - if they are wet, calibration alone will not save the print.

If your prints already look reasonably close to what you see in the slicer preview, there are really only two scenarios where tight calibration consistently pays off:

1. Intermateable parts
   If you are printing parts that must fit together, dimensional accuracy matters. That accuracy depends on both the printer and the filament calibration.

2. Smooth or artistic models
   This is especially true for silk filaments. Small calibration errors can become very visible under the right lighting.

Examples

Moist versus dry PC filament. Calibration will not fix this. The filament had to be dried. I dried it at 60C for 24 hours. The print on the left was made with wet filament.

Three examples using different filaments and calibration levels, all in the “artistic” category:

1. Left - calibrated single-color silk
2. Middle - uncalibrated multi-color silk
3. Right - PETG using a generic profile with pressure advance and flow rate calibrated

Note the fine, wispy stringing on the PETG. In this case, I simply used heat to burn it off rather than dialing the filament in further.

The the gold Benchy was printed using Bambu Gold Silk, which is no longer offered. Below is the same spool months later after being left out. Wet versus dry - and this is PLA, which many assume is immune to moisture.