What Resin Printing Actually Is

Resin 3D printing (technically MSLA — Masked Stereolithography) works completely differently from FDM. Instead of melting plastic, it uses UV light to cure liquid photopolymer resin, layer by layer.

The setup:

  • A vat (tank) holds liquid resin
  • A clear film at the bottom of the vat allows UV light through
  • An LCD screen below the film masks the UV light into the shape of each layer
  • A build plate descends into the resin, gets exposed to UV through the LCD mask, lifts up, descends again
  • Layer by layer, the build plate raises a fully-formed print up out of the resin

The result: stunning detail, no layer lines, fragile parts, messy workflow, and chemicals you don’t want to inhale.

Resin is the right tool for jobs FDM can’t do. It’s the wrong tool for most other jobs.

Resin vs FDM: When to Use Which

Use Resin For:

  • Miniatures (Warhammer, D&D, tabletop games)
  • Jewelry prototypes and casting models
  • Dental models, hearing aids, anatomical models
  • Highly detailed display pieces
  • Anything requiring sub-millimeter detail

Use FDM For:

  • Functional parts (brackets, fixtures, gears)
  • Large prints (anything over 200mm)
  • Items that need to be flexible or impact-resistant
  • Cost-conscious printing (filament is cheaper per kg of print volume)
  • Anything you’ll touch with bare hands regularly

The Workflow Difference

FDM: design → slice → print → done. Resin: design → slice → print → drain → wash in IPA → dry → UV cure → support removal → done.

Resin adds 30-60 minutes of post-processing per print. Worth it for the detail; painful for everything else.

What You Need to Buy

The Printer

For our current recommendations, see Best Resin 3D Printer . Quick picks:

  • Elegoo Mars 5 Ultra ($179) — Best entry-level, auto-leveling, 9K detail
  • Elegoo Saturn 4 Ultra ($299) — Best mid-range, 12K detail, big plate
  • Anycubic Photon Mono M7 ($249) — Biggest plate at this price (13.6")

The Wash & Cure Station ($150-300)

Non-negotiable. Hand-washing and hand-curing is miserable. The Elegoo Mercury Plus 2-in-1 ($200) is the standard recommendation — works with all major printer brands.

Resin ($25-50 per liter)

Beginner-friendly resins:

  • Elegoo ABS-Like Resin 2.0 ($30/L) — Forgiving, great for miniatures
  • Siraya Tech Tenacious ($45/L) — Stronger than standard, less brittle
  • Anycubic ABS-Like+ ($30/L) — Equivalent to Elegoo’s ABS-Like

Skip until you’re experienced:

  • Flexible resins (tricky settings)
  • Engineering resins (expensive, fussy)
  • Castable resins (jewelry-specific, $80+/L)

PPE You Actually Need

  • Nitrile gloves ($15 for 100) — replace torn ones immediately
  • Safety glasses ($10) — uncured resin can splash
  • Respirator with VOC filter ($30) — for ventilated rooms; or skip if you have proper exhaust
  • Disposable apron or work shirt — resin stains permanently

Workspace Setup

  • Ventilation — open window with fan, or proper exhaust hood
  • Dedicated table or area — not your bedroom, not your office
  • IPA (isopropyl alcohol) for washing — 91%+ concentration, bulk gallon ($25)
  • Paper towels and plastic spatulas — disposable scraping tools
  • A second container with IPA for final rinse

Total upfront cost (printer + wash/cure + PPE + first resin + accessories): $400-600 depending on printer choice.

How a Resin Print Goes (Start to Finish)

Step 1: Slice (15 minutes)

Open your model in Lychee Slicer (recommended) or Chitubox. Add support structures — resin needs them everywhere there’s overhang because the print is grown upside-down off the build plate.

Set your exposure time, layer height (0.05mm standard for minis), and lift speed.

Step 2: Print (4-12 hours)

Pour resin into the vat. Send the file to the printer. Hit print. Walk away.

Most failures happen in the first 5-15 layers. If you can confirm the print is sticking to the plate after the bottom layers, it’s likely to finish.

Step 3: Drain (10 minutes)

Print is done. Build plate is at the top with your model attached, dripping with uncured resin.

Let it drip back into the vat for 5-10 minutes. Don’t touch it — uncured resin is sticky and toxic to skin.

Step 4: Remove Plate (2 minutes)

Lift the plate off the printer. Place over a paper-towel-lined tray.

Step 5: Wash (5-10 minutes)

Place plate (or print, if you’ve removed it) into IPA wash station. Run for 3-5 minutes. The IPA dissolves uncured resin off the print’s surface.

Step 6: Dry & Inspect (5 minutes)

Remove from wash. Let IPA evaporate. Inspect for any unwashed spots — re-wash if needed.

Step 7: UV Cure (10-15 minutes)

Place in UV cure station. Set to 5-15 minutes depending on resin type. This finishes hardening the print.

Step 8: Remove Supports (5-30 minutes)

Pop supports off carefully. They leave little marks that you may want to sand or paint over.

Total post-processing time: 30-60 minutes per print. This is why resin is for high-value prints, not high-volume prints.

Common Resin Printing Mistakes

1. Skipping PPE

“I’ll just touch it once with my bare hand.” That’s how you develop a resin allergy. Once you’re sensitized, you can never print resin again without breaking out in rashes.

2. Bad Ventilation

Resin off-gasses VOCs (volatile organic compounds) during printing. In a closed room, levels build up to headache-inducing concentrations within hours. Always print in a ventilated space.

3. Pouring IPA Down the Drain

IPA contaminated with uncured resin is hazardous waste. Don’t pour it down the drain. Let it sit in sunlight for a day to UV-cure the resin into a sludge, then dispose of the sludge as solid waste and the cleared IPA can be reused.

4. Cheap Build Plates

The aluminum build plates that ship with most resin printers are fine. Aftermarket “magnetic flex plates” sound nice but are unnecessary for resin (you scrape prints off, you don’t peel them like FDM).

5. Not Pre-Heating

Cold resin (below 25°C) doesn’t cure properly. Keep your resin printer in a room that’s at least 70°F. In winter, use a small heating pad under the vat or pre-warm the resin.

Storage and Shelf Life

  • Sealed resin bottles last 1-2 years in a cool, dark place
  • Opened resin in the vat can sit for 1-2 weeks if covered (UV-blocking lid). Longer than that, drain back into the bottle and filter.
  • Cured prints are stable indefinitely indoors. UV-stable resins (rare) can go outdoors; standard resin yellows in sunlight.

What’s Next

Once you’re comfortable with basic resin printing:

  • Try abrasion-resistant or tough resins for functional miniatures
  • Learn print orientation tricks — angled prints with smart support placement minimize visible support marks
  • Experiment with hollowing and drain holes to save resin and cure faster
  • Get into mini painting — primed resin minis paint beautifully

For specific printer recommendations, see Best 3D Printer for Miniatures or Best Resin 3D Printer . For comparisons within the resin space, Saturn 4 Ultra vs Mars 5 Ultra covers the most common decision.