The Line Where the Toolhead Stops, Starts and Leaves Its Mark
Look closely at almost any FDM print and you will find a faint vertical seam — the point where each layer path closes. It is where the nozzle lifts, travels, and lays a tiny pause, and how you manage it decides whether that mark is nearly invisible or the first thing people notice.
Why the Seam Shows (and Why It Can Be Hidden)
The nozzle oozes a little as it waits, and the travel move can leave a small bead or a slight lip. Slicers give several strategies, and none is universally "best" — each trades one artifact for another:
- Aligned (nearest / sharpest corner): stacks every layer junction on one edge. Visible on that edge, but predictable and easy to sand away. Often hidden where a corner faces away.
- Random / scattered: spreads junctions so no single line dominates, at the cost of scattered small spots across the surface.
- On a chosen side: useful for parts with a hidden or non-critical face — put the seam exactly where inspection won't look.
Settings That Do the Heavy Lifting
Retraction and coast wipe control how much material is left at the junction. When a seam looks like a raised zit, add a touch of wipe or a small coast; when it looks dug-in or pockmarked, ease retraction back a fraction. Because oozing differs by material, re-check when you switch spools:
- PLA+ strings least, so a light wipe is usually enough.
- PETG is stickier — it needs a tuned retraction plus a slower wipe to avoid both hairs and pockmarks.
- ABS balances on temperature: too hot oozes, too cool gaps, so an enclosed, even chamber counts.
- TPU needs the lowest speeds and a very direct path, since flex pushes the pause artifact around.
Turn the Defect Into Data
Print one small calibration with the seam options shown side by side, then pick by eye and feel. Because the artifact belongs to the travel, not the wall, you can hide it without weakening the part — the mark moves, it does not disappear. Learning to place that seam deliberately is one of the quickest quality wins in FDM.
Everyday filaments that behave predictably — ANTINSKY PLA+ Filament 1.75mm 1kg, ANTINSKY PETG Filament 1.75mm 1kg, ANTINSKY ABS Filament 1.75mm 1kg and ANTINSKY TPU 95A 1KG 1.75mm — are all stocked at innostation3d.com.