Open this lesson in your favourite AI. It'll walk you through the why, explain the demo, and quiz you on the try-it list.
The vast majority of hobby printing is FDM (fused deposition modeling — what we've been talking about), but you should know what the other technologies do well so you reach for them when they're the right tool. SLA gives you smooth, miniature-quality surfaces FDM can't match. SLS gives you isotropic functional parts with no supports. Knowing the trade-offs lets you outsource the right job to the right service when needed.
When each technology wins.
Use these three in order. Each builds on the one before.
In one paragraph, explain when SLA beats FDM for a hobbyist.
Walk me through the SLA print cycle: how does the photopolymer cure layer by layer, and why does it need supports?
I want to make 50 identical functional nylon parts with a snap-fit. Should I FDM at home, outsource to SLS, or look at injection molding? Justify by part cost and lead time.
Property FDM SLA (Resin) SLS (Powder)
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Hobby entry price $200-$2000 $200-$1500 $5000+ (services only)
Layer thickness 0.08-0.32mm 0.025-0.10mm 0.06-0.12mm
Surface finish Visible layer Smooth/glassy Fine sandpaper
lines (with anti-aliasing)
Anisotropy Strong (weak Mild Almost none
in Z)
Support needed? Often Usually No (powder supports)
Post-process effort Low Wash + UV cure Powder removal
Mess factor Almost none Sticky resin + Lots of powder
IPA washing
Material toxicity Low (PLA fumes) Resin is irritant Powder is inhalation risk
Higher for ABS Wear nitrile gloves Need mask + cabinet
Best for FDM:
- Functional / mechanical parts
- Large prints (≥ 100mm any dimension)
- Anything you'll throw in a drawer and forget
- Prototyping new CAD models cheaply
Best for SLA:
- Miniatures, dental, jewelry
- Small parts needing very fine detail
- Smooth aesthetic surfaces
- Functional fluidic / optical parts where surface matters
Best for SLS:
- Production-grade nylon parts
- Complex geometries with internal channels (no supports!)
- Functional snap-fits and living hinges at scale
- Outsource: JLCPCB MJF, Shapeways SLS, Sculpteo