Kate G. - August 25st, 2025
SUNLU SP2 Filament Dryer Review
If you’ve ever struggled with brittle PETG, stringy PLA, or foamy nylon, you know filament moisture is the silent killer of print quality. SUNLU—a trusted name in 3D printing accessories—claims its SP2 Dryer solves this for good. After testing it for a month alongside other SUNLU dryers, here’s our honest take.
What Makes the SP2 Special?
The SP2 isn’t just a refresh—it’s a complete redesign focused on usability, safety, and performance:
●Dual-Zone Heating: Dries two spools simultaneously (up to 3kg total)
●55°C–70°C Precision Control: Handles everything from PLA to nylon
●Time Setting Range: 0-99h: Offers unparalleled flexibility for long-term drying cycles
●Rolling-Compatible Design: Print directly from the dryer during operation
●Strong Safety, Stress-free Use: Equipped with over-temperature protection and automatic power-off functionality for worry-free operation
Vs. Other SUNLU Dryers: Which Should You Buy?
Key Advantage: The SP2's higher temperature range and extended timer make it the only SUNLU dryer capable of handling technical filaments like PA-CF or PC through extended drying cycles.
Real-World Testing: How Effective Is It?
We tested with moisture-sensitive PETG that had been left open for 2 weeks:
●Before Drying: 0.60% moisture (measured by precision scale)
●After 6h in SP2: 0.28% moisture
●Print Results: Stringing reduced by ~90%
The safety features proved valuable when we intentionally tested the over-temperature protection - the unit automatically shut down within 3 seconds of exceeding safe parameters.
Bonus: The low-noise fan (≤35dB) won't distract you in a home office.
The Downsides: Where SUNLU Missed the Mark
1·No Dedicated Exhaust Vent
Unlike competitors like eBox, the SP2 lacks a specific moisture exhaust port. While it does remove humidity through subtle gaps, it's less efficient for extremely wet filament. We noticed slightly longer dry times compared to vented models.
2·Dim Screen with Poor Viewing Angles
The LCD is noticeably dimmer than other dryers in its class. You'll need to be directly in front of it to read settings—forget checking status from across the room. This feels like a cost-cutting measure in an otherwise premium product.
Who's It For?
✔ Multi-material users who print with nylon, PC, or other hygroscopic filaments
✔ High-volume printers needing to dry 2+ spools at once
✔ Safety-conscious users who value automatic protection features
✔ Anyone tired of oven-drying disasters (RIP to my melted PLA spool)
Skip If:
❌ You only print with PLA (the cheaper S2 suffices)
❌ You need industrial-scale drying (look at PrintDry Pro)
Verdict: Best-in-Class with Minor Flaws
The SP2 isn't perfect—the lack of dedicated venting and disappointing screen hold it back from greatness. But for most users, its dual-zone heating, extended timer range, safety features, and roll-while-drying capability make it the best dryer under $100.
Rating: 8.5/10
●Performance: 9.5/10
●Safety: 9.0/10
●Usability: 7/10
●Value: 9/10
Deal Alert: The SP2 often drops to $79 on Amazon—a steal versus the $119 Comgrow dryer with similar specs.
