Lychee Slicer for Resin 3D Printing: Smart Supports, Hollowing, and Anti-Aliasing Explained

Every resin printer we've covered on this site — the Elegoo Saturn 3 Ultra, the Anycubic Photon and Mars lines, the Formlabs Form 4 — ships with its own slicer, and most people just use whatever came in the box: CHITUBOX for the Elegoo and most generic MSLA machines, PreForm for Formlabs. Lychee Slicer is the third option almost nobody starts with but a lot of experienced resin printers switch to, and it's worth understanding even if you never install it, because the features it popularized — auto-orientation that actually works, one-click smart supports, and real anti-aliasing control — are the things people mean when they complain that their stock slicer "doesn't do a good job" with supports.

Where Lychee fits

Lychee Slicer (made by Mango3D) is a standalone, printer-agnostic slicer that exports standard sliced files for most mainstream MSLA/LCD resin printers — it reads your printer's build volume and exposure profile either from a built-in printer database or an imported machine profile, and outputs the same .ctb, .pwmx, or generic .sl1-style formats your printer's firmware expects. You install it alongside, not instead of, your printer's bundled software; many people keep CHITUBOX or the OEM slicer around for quick jobs and reach for Lychee specifically when a model has tricky geometry — minis with thin weapons and overhangs, cosplay props with large overhung surfaces, or anything where supports showing up on a visible face is a real problem.

Smart supports: what's actually different

Every resin slicer can generate supports. The difference with Lychee is in how it decides where to put them and how it shapes the contact points:

• Surface-aware placement — Lychee's auto-support algorithm analyzes the mesh for overhang angle and cross-sectional thickness simultaneously, rather than just overhang angle. In practice this means fewer supports on thin features that would snap under a heavy support's pull force, and more supports concentrated under genuinely unsupported mass.
• Light, medium, and heavy support profiles with per-point editing — you can globally pick a density, then manually add, delete, or resize individual support tips and the mid-section strut thickness without starting over, which matters a lot on a 40-minute-to-slice miniature with 200+ auto-generated points.
• Raft and base options tuned per printer profile — because Lychee knows your specific printer's plate adhesion characteristics from its profile, raft density and the first-few-layer exposure boost it recommends are matched to that machine rather than being a generic guess.

The practical result: on a model with a lot of thin overhangs (think miniatures with capes, outstretched weapons, or wide-brimmed hats), Lychee's auto-support pass typically needs far less manual cleanup than CHITUBOX's default algorithm before you're ready to slice.

Hollowing and drainage

Hollowing a model before printing saves resin and dramatically cuts print time on large parts, but it only works if the hollow shell can actually drain uncured resin and vent trapped air during printing — get this wrong and you get a part that either doesn't cure right or literally explodes off the plate from trapped gas pressure. Lychee's hollow tool lets you set wall thickness, then auto-place drain holes based on where resin would pool given your chosen print orientation, with a preview that shows projected low points. For anything larger than a simple figurine, add at least two drain holes on opposite low points, sized at 3-4mm minimum diameter — smaller holes clog with partially-cured resin far more often than people expect.

Anti-aliasing: the setting most people never touch

Anti-aliasing (AA) controls how the slicer handles pixel edges on your LCD-masked printer — without it, curved surfaces print with visible stair-stepping at the pixel boundary, because each layer is either fully exposed or fully masked per pixel with no in-between. Lychee exposes both horizontal (within-layer) and grayscale AA controls:

SettingWhat it doesTrade-off Anti-aliasing level (e.g. 1-8)Sub-pixel grayscale blending at edges, smoothing curved surfacesHigher levels smooth more but can slightly soften genuinely sharp edges and fine engraved detail Blur levelAdditional edge softening pass on top of AAUseful for very smooth organic surfaces (miniature skin, fabric folds); can mush fine text or thin lines if overused Pixel grey level / exposure gradingHow aggressively intermediate pixel brightness maps to partial cureToo aggressive can under-cure thin walls at their edges, leaving them weak

A reasonable starting point for general miniature and prop printing is AA level 4 with blur level 1-2; for mechanical parts where dimensional accuracy on flat faces matters more than curve smoothness, drop AA to 2 or off entirely and rely on your exposure profile instead.

A practical first workflow

1. Import your model and select your printer profile from Lychee's built-in database (or add a custom profile with your exact build volume and exposure times if your printer isn't listed).
2. Run auto-orientation — Lychee's version weighs supportable surface area against print height rather than just minimizing height, which usually gives a more support-friendly result than a naive "shortest print time" orientation.
3. Hollow if the part is large or solid-heavy, check the drain hole preview, and adjust placement manually if the auto-placed holes land on a visible face.
4. Run auto-support at a medium density, then spend a few minutes reviewing and hand-editing the riskiest overhangs before accepting.
5. Set AA and blur per the guidance above, slice, and export to your printer's native format.

Lychee's free tier covers everything above for personal use; the paid Pro tier adds batch processing and some automation features aimed at people running multiple printers for small-batch production. Either way, if you've been fighting your stock slicer's supports on anything with thin overhangs or visible-face geometry, it's worth the twenty minutes it takes to install Lychee alongside your existing workflow and compare the support job it generates on the same model.