The dimensional accuracy of the Raise3D RMS220 system in the X, Y, and Z directions meets the following specifications:
| Item | Tolerance / Repeatability Requirement |
|---|---|
| X/Y-axis Tolerance | - For features ≤ 100 mm: ±0.3 mm - For features > 100 mm: ±0.3% of the measured dimension |
| Z-axis Tolerance | - For features ≤ 100 mm: ±0.5 mm - For features > 100 mm: ±0.5% of the measured dimension |
| X/Y-axis Repeatability (Printing identical models in the same build chamber under consistent conditions) | High repeatability achieved: up to ±0.2% |
Notes:
- Z-axis Accuracy Clarification:
For complex or low-density geometries (e.g., lattice structures or hollow designs), actual thermal shrinkage behavior may significantly deviate from standard test models—especially in large Z-direction builds, where dimensional deviations become more pronounced. Therefore, the standard tolerance range (±0.5 mm or ±0.5%) may not fully apply to such parts. It is recommended to perform part-specific scaling compensation based on geometry and build orientation to achieve stable and accurate dimensions.- Definition of "complex or low-density geometries":
These typically refer to lightweighted designs, parts with lattice infill, or complex hollow internal structures.- Test Material:
All stated accuracy values are based on testing with PA12 Black Powder(v1.5).- SLS printing of TPU is fundamentally different from printing nylon (PA12). TPU is an elastomer, and its low modulus of elasticity and unique thermal behavior dictate the following design principles:
Looser tolerance requirements: TPU parts typically exhibit lower dimensional accuracy than PA12. Typical tolerances are:
For dimensions within 0–100 mm range: ±0.5 mm in X, Y, and Z directions.
For dimensions >100 mm: ±0.5% in X and Y directions.
Increased measurement difficulty: Elastomeric parts easily deform under hand pressure during measurement. It is recommended to use dedicated fixtures for dimensional inspection.
Our powder recycling printing method, when repeated at the recommended ratio, ensures consistent model dimensions. If significant dimensional deviations are observed, please check the following:
Two primary parameters jointly determine X/Y dimensional outcomes:
If you observe consistent dimensional deviation across a batch of parts, do not adjust either parameter in isolation—this may introduce more complex errors. Instead, follow our complete dimensional calibration guide to properly tune both parameters together.
Z-axis dimensions are primarily influenced by the Z-scaling factor. However, due to a phenomenon known as “secondary sintering” (approximately 0.2 mm of additional laser penetration into the first layer), we have mitigated this effect by reducing laser power on the bottom surface.
For horizontally printed thin-walled parts (<1 mm thick), slight reduction in bottom-surface mechanical strength may occur—though this scenario is rare in practice. We are currently developing an independent bottom-surface compensation parameter to better balance structural integrity and fine-detail accuracy in future updates.
Note:
- Laser energy penetrates slightly beyond the intended layer, causing this secondary sintering effect.
- Z-direction error distribution tends to be larger than in X/Y across the build volume. This is because powder-pack cooling occurs from the outside inward—central regions retain heat longer, leading to greater crystallization shrinkage and slightly reduced part height compared to edges.
Yes. Crystalline shrinkage is also influenced by a model’s solidity rate (i.e., material density). For example, a fully solid part and a lightweighted version of the same geometry (e.g., with lattice infill) will exhibit noticeably different final dimensions after printing.
Our system, once calibrated, accommodates most common geometries. However, extreme cases—such as large solid parts or large sparse lattice structures—carry a higher risk of dimensional deviation. If your application involves such designs, please consult our Design Guidelines or contact our support team for tailored recommendations.
A: The RMS220 delivers highly repeatable results. Under consistent process parameters and compliant material usage, dimensional variation between batches remains negligible.
Note: Dimensional outcomes depend on both precision (repeatability) and accuracy (closeness to target). Refer to the dartboard analogy: high precision = tight cluster of hits; high accuracy = hits near bullseye. Optimal results require both.
A: Regular verification of the six key factors above is essential. The RMS220 features an intelligent monitoring system that provides real-time alerts for core component status. Combined with scheduled maintenance per the service manual, long-term dimensional stability is effectively maintained.
A: Accuracy specifications are tiered as follows:
| Feature Size | Tolerance |
|---|---|
| < 100 mm | ±0.3 mm |
| ≥ 100 mm | ±0.3% × L (length) |
Although the absolute tolerance increases with size (e.g., ±0.3 mm at 50 mm vs. ±0.6 mm at 200 mm), the relative accuracy remains consistent.
Why two tiers? Because SLS process errors arise from two distinct mechanisms:
1. Inherent System Errors (Dimension-Independent)
These errors do not change with the size of the part; they are a fixed value.
These types of errors have a significant impact on small-sized features—if a 10 mm feature is off by 0.3 mm, the relative deviation is 3%, which is already very significant.
2. Cumulative Shrinkage Error (Proportional to Size)
This type of error increases linearly with the feature size, representing a proportional value:
This type of error has a significant impact on large-sized features—a 200 mm feature controlled with only ±0.3 mm absolute tolerance is equivalent to requiring a relative accuracy of 0.15%, which is too stringent for SLS processes.
3. Synthesis Logic
Actual size deviation = inherent system error + cumulative shrinkage error, where the former is a constant term and the latter is a proportional term. Therefore:
| Feature Size | Dominant Error | Reasonable Expression |
|---|---|---|
| Small (< 100 mm) | System-inherent error dominates | Expressed as absolute value: ±0.3 mm |
| Large (≥ 100 mm) | Cumulative shrinkage error dominates | Expressed as percentage: ±0.3% |
A: For high-precision applications, periodic accuracy verification is recommended. If deviations exceed specifications, perform a full calibration. For special use cases or anomalies, our technical support team offers customized diagnostics and optimization guidance to ensure consistent print quality.