If you’re designing parts forLaser Sintering Molding (SLS)—a top-tier powder bed fusion 3D printing tech—great design isn’t just “nice to have.” It’s the difference between a part that cracks mid-use and one that’s strong, دقيق, وفعالة من حيث التكلفة. This guide breaks down every critical design rule for SLS, مع أمثلة في العالم الحقيقي, بيانات, and tips to fix common headaches like warping or stuck powder.
1. Why SLS Design Rules Matter
SLS uses lasers to fuse thermoplastic powders (يحبالسلطة الفلسطينية 12 or carbon-filled polyamide) into parts. على عكس FDM, it doesn’t need support structures—but its powder-based process creates unique design challenges:
- Thin walls can collapse under laser heat.
- Small holes trap unsintered powder (ruining functionality).
- Large flat surfaces warp as the part cools.
اتبع هذه القواعد, and you’ll cut reprints, save material, and get parts that work right the first time.
2. Critical SLS Design Guidelines (مع البيانات & أمثلة)
We’ve organized the most important rules by feature—from wall thickness to text. Each section includes easy-to-use tables and real cases to guide you.
2.1 سمك الجدار: Avoid Collapse & تكسير
Wall thickness is make-or-break for SLS parts. رقيقة جدا, and the part will collapse during printing; سميك جدا, and you waste material (والمال).
Key Recommendations by Material
| نوع المواد | Minimum Wall Thickness (With Support) | Minimum Wall Thickness (No Support) | Preferred Thickness (For Consistency) | Maximum Recommended Thickness |
|---|---|---|---|---|
| السلطة الفلسطينية 12 (نايلون) | 0.6 مم | 0.7 مم | 1.3 مم | 4 مم |
| Carbon-Filled Polyamide | 1.0 مم | 2.0 مم | 1.3–1.5 mm | 4 مم |
مثال حقيقي:
A manufacturer designed a PA 12 bracket with 0.5 جدران مم (too thin!). The laser’s heat melted the thin sections, تسبب 80% of the parts to collapse. When they adjusted to 1.3 جدران مم, the success rate jumped to 99%—and they still saved 30% material vs. أ 4 mm wall design.
للنصيحة:
Walls thinner than 0.5 mm willoverthicken from the laser’s heat. Stick to the minimums above to avoid distorted parts.
2.2 Hole Sizes: Prevent Trapped Powder
SLS prints holes directly—no need for post-drilling. But small holes trap unsintered powder, which can block fluid flow (للصمامات) or break the part when you try to remove it.
Must-Follow Hole Rules
- Minimum diameter: 1.5 مم (any smaller traps powder).
- أفضل الممارسات: Design holes to match standard drill bit sizes (على سبيل المثال, 2 مم, 3 مم). If the hole needs to be precise, you can drill it slightly larger post-print.
مثال حقيقي:
A medical device company printed PA 12 filters with 1.0 mm holes. بعد الطباعة, they couldn’t remove the trapped powder—rendering 50% of the filters useless. When they increased holes to 1.5 مم, powder came out easily, and the filters worked perfectly for fluid filtration.
2.3 حجم الجزء: Stay Within Printable Limits
SLS printers have maximum and minimum size limits. Going beyond them leads to failed prints or low precision.
SLS Size Guidelines
| متري | مواصفة |
|---|---|
| Maximum Printable Size | 340 x 340 x 605 مم |
| Recommended Max Size | 320 x 320 x 580 مم (avoids edge warping) |
| الحد الأدنى لحجم الميزة | 0.5 مم (printable, but risky) |
| Recommended Min Size | 0.75 مم (for consistent results) |
للنصيحة:
If your part is larger than 320 x 320 x 580 مم, split it into smaller interlocking pieces. SLS can print parts that fit together perfectly—saving you from oversized print failures.
2.4 التسامح: Focus Only on What Matters
Tolerance is how much a part’s size can vary. Too many tight tolerances increase print time and cost; too few ruin mating parts (like a lid that won’t fit a box).
SLS Tolerance Facts
- Maximum accuracy: حتى 0.3% of the feature size (أو 0.3 mm—whichever is larger). على سبيل المثال, أ 100 mm part can vary by ±0.3 mm.
- حكم الإبهام: Only use tight tolerances for mating surfaces (على سبيل المثال, a shaft that fits a bearing). For non-critical areas (على سبيل المثال, a part’s outer edge), loosen tolerances to save time.
مثال حقيقي:
An automotive supplier added tight tolerances (± 0.1 مم) to every part of an SLS bracket—even the non-mating edges. This doubled print time and cost. When they limited tight tolerances to just the mating hole, they cut costs by 40% with no loss in functionality.
2.5 Hollow Parts: Add Escape Holes for Powder
Hollow parts save weight and material—but you needescape holes to remove residual powder from the cavity.
Hollow Part Rules
- Minimum escape hole size: 3.5 مم (smaller holes trap powder; larger holes let media in for interior polishing).
- Where to place holes: Put them in hidden areas (على سبيل المثال, the bottom of a hollow cup) so they don’t ruin aesthetics.
مثال حقيقي:
A luggage brand printed hollow PA 12 handles with no escape holes. بعد الطباعة, the trapped powder made the handles heavy and brittle. When they added two 3.5 mm holes, powder poured out easily—the handles were 25% lighter and passed drop tests.
2.6 Interlocking Parts: Print Functional Assemblies in One Go
SLS’s superpower? Printing interlocking, أجزاء متحركة (like hinges or gears) in a single build—no assembly needed. But you need enough clearance to remove powder.
Interlocking Part Rule
- Minimum clearance: 0.5 mm between moving parts (على سبيل المثال, a gear and its axle). More clearance (0.8-1.0 مم) is better for easy movement.
مثال حقيقي:
A toy company printed a SLS gear set with 0.3 mm clearance. Powder got stuck between the gears, making them lock up. When they increased clearance to 0.5 مم, the gears spun smoothly—no assembly required.
2.7 Engravings, Embossings & Text: Keep Them Visible
SLS can print logos, نص, or details directly on parts—but small details wear off during post-processing (like media tumbling).
Detail Guidelines
| Feature Type | Minimum Size Requirement | نصائح للمحترفين |
|---|---|---|
| Engravings/Embossings | 1 mm depth/height | Prevents wear during media tumbling |
| Text | 2 mm height | يستخدمSans serif fonts (على سبيل المثال, Arial) for readability |
| Fragile Letters (على سبيل المثال, “i”) | Add a small draft (5–10°) | Stops them from breaking in post-processing |
مثال حقيقي:
A electronics brand printed PA 12 cases with 1.5 mm tall text (صغير جدا!). Media tumbling wore the text down, making it unreadable. When they increased text height to 2 mm and used Arial, the text stayed clear—even after polishing.
2.8 Avoid Warping: Skip Large Flat Surfaces
أسطح مسطحة كبيرة (على سبيل المثال, أ 200 مم x 200 لوحة مم) warp as SLS parts cool. The powder shrinks unevenly, causing the surface to bow or crack.
كيفية إصلاحه
- قاعدة 1: Avoid large flat surfaces whenever possible.
- قاعدة 2: If you need a flat surface, يضيف أضلاع (thin support structures) underneath. Ribs should be 0.8–1.0 mm thick and spaced 10–15 mm apart.
مثال حقيقي:
A furniture maker printed large flat SLS PA 12 لوحات (300 مم x 200 مم) with no ribs. 70% of the panels warped by 2–3 mm. When they added 1.0 mm ribs spaced 12 مم, warping dropped to less than 0.5 mm—perfect for their furniture designs.
3. Yigu Technology’s Take on SLS Design
في Yigu Technology, we’ve helped hundreds of clients fix SLS design issues. أكبر خطأ نراه? Overlooking small details—like 0.3 mm clearance for interlocking parts or 1 mm engravings. نصيحتنا: Prioritizefunction first—match wall thickness, حجم الثقب, and clearance to how the part will be used. على سبيل المثال, a medical part needs tighter tolerances than a decorative one. By aligning design with end-use, you’ll get SLS parts that are strong, دقيق, and cost-efficient—every time.
4. التعليمات: Common SLS Design Questions
س 1: Can I print a wall thinner than 0.7 mm for PA 12 if I use support?
نعم, but only down to 0.6 mm—and it’s risky. The laser’s heat can still overthicken or collapse 0.6 جدران مم. We recommend sticking to 0.7 مم (no support) for consistent results.
Q2: Why do I need to use Sans serif fonts for SLS text?
Sans serif fonts (no small “tails” on letters) have simpler shapes. This makes them easier for the SLS laser to print clearly, and they’re less likely to break off during post-processing compared to serif fonts (على سبيل المثال, Times New Roman).
س 3: If my part is larger than 340 x 340 x 605 مم, can I still print it with SLS?
No—SLS printers can’t go beyond their maximum build size. بدلاً من, split the part into smaller interlocking pieces (مع 0.5 mm+ clearance). SLS prints these pieces perfectly, and you can assemble them post-print for a full-size part.