Why slicer presets are only starting points
TL;DR presets are fine for toys and trinkets. Proper calibration is what makes functional parts fit.
I’ve posted about this before, but it keeps coming up, so I’m repeating it to emphasize the point.
So this really applies to functional prints. If you’re printing decorative stuff, fidget toys, desk trinkets, or anything where fit and strength don’t really matter, presets are generally fine.
For functional parts, though, slicer presets are a useful starting point only.
They are not proper calibration and they are definitely not tuned for your printer. They are just a set of reasonable defaults meant to work well enough on a lot of different configurations. They assume things like: dry filament, a certain types of nozzles, average thermal behavior, safe flow limits, and generic dimensions.
I get asked pretty often to share my settings for a specific filament. I get it, but it is usually not that helpful for functional prints. Those settings only really make sense on my printer, with my nozzle, in my environment, and with whatever moisture state that filament happened to be in. Copying them to a different setup often gives mixed results, even with the same brand and color of filament.
As soon as anything changes, different filament, different color, different nozzle material, a high flow nozzle, or even just drying the filament after you have already printed with it, the preset or copied profile stops matching reality.
That is why functional parts so often almost fit after a long print and wasted filament.
Calibration is replacing assumptions with measurements. It is how you deal with the stuff presets cannot assume, like how dry the filament actually is, what temperature really works with your nozzle, how much plastic you can push, how your corners behave, and how much the material shrinks.
Presets and shared profiles are a fine place to start. They are just not where you should stop if fit and reliability matter to you.
I'm assembling an article on Printables that explains my calibration process. Will link it here when I'm done.
RE: Why slicer presets are only starting points
Would add here that if you are primary printing PLA/PETG and stuff you've downloaded from Printables you can generally ignore this advice. It applies when using engineering filaments and accuracy is key.
RE: Why slicer presets are only starting points
OK, here is the article I "wrote". Disclaimer, as an experiment, I tried an AI (chatGPT 5.2) for this one. Gave it a list of things I wanted and asked it to turn it into an article for Printables. I probably won't do it again because I had to spend time too much time to "correct" it.
https://www.printables.com/article/how-to-properly-calibrate-filaments-for-functional-wdkbBl5
RE:
Filament Calibration Checklist
- Dry filament to manufacturer-appropriate moisture level.
- Heat-soak printer to normal printing temperatures (bed, chamber, enclosure).
- Print temperature tower and select the lowest temperature with clean layers and strong bonding.
- Measure max volumetric flow and set a safe limit at ~75–80% of the measured maximum.
- Calibrate extrusion multiplier (single-wall / vase-mode) at the chosen temperature and flow limit.
- Calibrate pressure advance at real print speeds and near the flow limit.
- Measure XY shrinkage (Califlower or equivalent) with shrink compensation disabled.
- Apply XY shrinkage compensation in the filament profile and verify once.
- (Optional) Verify warp behavior using a representative long or flat part.
- Freeze the profile and only re-calibrate if filament, nozzle, or thermal conditions change.
Notes:
- For the temperature tower and max volumetric flow I used the tests built-in to OrcaSlicer.
- Extrusion muliplier. In PrusaSlicer create a 40mm box. Set to vase mode, turn off variable layer height, set top bottom layer to 0. Use a micrometer to measure wall thickness (not a caliper). Take 12 measurements in the middle around the box (3 per side) and average.
- For pressure advance
- XY shrinkage Califlower Calibration Tool Mk2