3D Print Stringing and Layer Adhesion Issues? Filament Moisture Might Be the Cause — SUNLU E2 Dryer and Annealing Guide

Have you ever noticed string-like residue, gaps between layers, or rough surfaces when 3D printing? Many of these issues are actually caused by filament absorbing moisture from the air. Meanwhile, many users struggle with insufficient strength or warping in their prints. PLA in particular is easy to print with but lacks strength and heat resistance. Did you know that proper annealing treatment can dramatically improve these problems?

The SUNLU E2 we’re introducing here is an innovative device that handles both filament drying and annealing in a single unit. This product is currently running a crowdfunding campaign on CAMPFIRE, offering a chance to purchase at a discount compared to the regular retail price.

The Filament Moisture Problem: Why Drying Is Essential

3D printing filaments are inherently prone to absorbing moisture from the air. Common materials like PLA, ABS, and PETG begin absorbing moisture within just days of opening. No matter how high-performance your 3D printer is, if the filament contains moisture, you can’t achieve its full potential. Filament management is the absolute foundation of high-quality printing.

Problems Caused by Moisture-Laden Filament

• Stringing: Molten resin dripping from the nozzle leaves string-like residue
• Surface roughness: Small bubbles form as moisture evaporates, creating rough surfaces
• Layer adhesion failure: Weakened inter-layer bonding causes delamination
• Dimensional accuracy loss: Uneven expansion and contraction
• Nozzle clogging: Steam bubbles cause problems inside the nozzle

What Is Annealing? Heat Treatment That Dramatically Improves Print Strength

Annealing is a heat treatment process that rearranges the internal molecular structure of printed plastic parts by heating them at a specific temperature for a set duration. For PLA filament, heating near the glass transition point (approximately 60°C) increases crystallinity, improving both strength and heat resistance.

Benefits of Annealing

• Mechanical strength improvement: Tensile and flexural strength increase by up to 40% or more
• Heat resistance improvement: Higher heat deflection temperature enables use in hot environments
• Internal stress relief: Reduced warping and distortion improve dimensional stability
• Inter-layer bonding strengthening: Increased strength in the layer direction makes parts more crack-resistant

Previously, annealing was done manually using ovens or heat guns. However, temperature management was difficult, and issues like deformation from overheating and quality inconsistency from uneven heating were common challenges.

SUNLU E2 Features: Two Functions in One Innovative Design

The SUNLU E2 integrates filament drying and annealing functions into a single device designed for 3D printing enthusiasts. Its intuitive operation and precise temperature control make it accessible for beginners through advanced users:

• Dual mode: Switchable between drying mode and annealing mode
• Precise temperature control: Settable from 35°C to 70°C in 1°C increments
• Large capacity: Accommodates 1kg filament spools and medium-sized prints
• Quiet operation: Low noise that won’t disturb your workspace
• Timer function: Up to 48 hours of continuous operation
• Transparent window: Monitor processing status from outside

Notably, optimized preset programs are provided for each material type. For example, PLA is preset at 55°C and ABS at 65°C, enabling proper treatment even without specialized knowledge.

Filament Drying Mode: Optimal Settings by Material

The SUNLU E2’s drying mode supports temperature settings for various filament materials. Applying appropriate drying treatment for each material maximizes print quality:

• PLA: 45–50°C for 4–6 hours (absorbs moisture easily but treatable at low temperatures)
• ABS: 60–65°C for 4–6 hours (requires higher temperatures but shows dramatic results)
• PETG: 55–60°C for 6–8 hours (highly hygroscopic, longer drying recommended)
• Nylon: 70°C for 12+ hours (most hygroscopic, thorough drying essential)
• TPU: 50°C for 4 hours (flexible material, low temperature and short duration is the standard)

Over-drying can also be problematic, so proper time and temperature management matters. The SUNLU E2’s timer function helps prevent over-drying while achieving optimal results.

Annealing Mode: Maximizing Print Strength

In annealing mode, place finished parts inside the chamber and heat at the appropriate temperature for the material. For PLA, the standard is 60–65°C for 1–2 hours.

Tips for Effective Annealing

• Temperature setting: Aim for 5–10°C below the material’s glass transition point
• Heating time: 1–3 hours depending on part size and thickness
• Cooling process: Allow natural cooling inside the chamber — don’t rapid-cool
• Support method: Place on flat surfaces or support appropriately to prevent deformation

Practical Use Cases: Where the SUNLU E2 Excels

When Filament Drying Is Especially Important

• Before using long-stored filament
• Before printing in rainy season or high-humidity environments
• Reviving filament that’s been open for several weeks
• When creating precision prints or transparent parts
• Troubleshooting when stringing occurs frequently

When Annealing Is Most Effective

• Mechanical parts and structural components requiring strength
• Parts used in high-temperature environments (inside cars, outdoors)
• Screw holes and snap-fit areas requiring precise dimensions
• Large prints prone to warping and distortion
• Thin-walled parts at risk of layer delamination

For example, when creating functional prototypes, dry your filament first, then print, and finally apply annealing treatment — achieving strength and quality close to commercial products.

Comparison with Other Drying and Annealing Methods

Conventional Drying Methods

• Food dehydrators: Temperature control possible but not designed for filament, making usability challenging
• Ovens: Home ovens have temperature inconsistency and high risk of overheating
• Sealed containers + desiccant: Effective for preventive storage but slow for reviving already-moist filament

Conventional Annealing Methods

• Ovens: Most common but difficult temperature management and high deformation risk
• Heat guns: Effective for localized treatment but uniform heating is difficult
• Hot water: Works for some materials but introduces moisture issues and temperature control problems

The SUNLU E2, designed specifically for 3D printing, excels in temperature control precision, ease of use, and safety. Covering both functions in a single unit also offers excellent space efficiency.

CAMPFIRE Crowdfunding Details

The SUNLU E2 is currently running a project on CAMPFIRE, Japan’s crowdfunding platform, offering a chance to purchase at a discount before general retail. Benefits include early-bird pricing, priority shipping, and potential bonus accessories or extended warranty. However, crowdfunding carries risks such as potential delivery delays and minor specification changes — review the project page carefully before backing.

Tips for Getting the Most Out of the SUNLU E2

• Make it a habit to dry filament immediately after opening
• Record optimal temperatures and times for each material to find your personal best settings
• Use both before and after printing to maximize quality
• Maintain the chamber regularly to keep it clean
• When drying multiple filaments simultaneously, group by material type

After drying, store filament in sealed containers with desiccant to extend the effect. Combining the SUNLU E2 with proper storage creates an environment where you always use filament in optimal condition.

Conclusion: A Worthwhile Investment in 3D Print Quality

The SUNLU E2 is an innovative device covering two critical processes that determine 3D print quality — filament drying and annealing — in a single unit. It’s a highly valuable investment for intermediate and advanced users aiming to improve their print quality. It’s especially recommended for those struggling with stringing and layer adhesion issues, those wanting to improve part strength and durability, users working with multiple materials pursuing high-quality output, those creating functional prototypes and practical parts, and anyone looking to seriously level up their 3D printing setup.

3D print quality depends not only on printer performance but significantly on filament condition and post-processing. The SUNLU E2 supports all these processes, serving as a reliable partner to take your 3D printing experience to the next level.

ブラウザだけでできる本格的なAI画像生成【ConoHa AI Canvas】

swiftwand

X

AIを使って、毎日の生活をもっと快適にするアイデアや将来像を発信しています。 初心者にもわかりやすく、すぐに取り入れられる実践的な情報をお届けします。 Sharing ideas and visions for a better daily life with AI. Practical tips that anyone can start using right away.