Dimensional accuracy describes how closely a manufactured feature matches its intended dimension. Repeatability concerns consistency across repeated results. A tolerance defines the acceptable variation for the feature and application.
For an MJF part, use those distinctions to agree what the supplier must deliver. A general statement about a printing technology is not a substitute for acceptance criteria on your drawing.
Do not treat a general tolerance as a universal guarantee
Ask the manufacturer what tolerance applies to the specific material, machine, geometry, feature size, orientation, and finishing route. Clarify whether it describes a general offering or a demonstrated capability for your part.
HP publishes a Multi Jet Fusion handbook covering design and dimensional-tolerancing topics. Use the guidance relevant to the intended process together with the supplier's capabilities. Do not combine a minimum-feature recommendation from one configuration with an accuracy claim from another.
Layer height, image resolution, minimum printable detail, and dimensional tolerance are different specifications. A fine detail that can be reproduced visually is not necessarily a feature whose size or position can be held to your assembly requirement.
Identify the dimensions that matter
Mark the features that control fit or function, and supply the drawing and model revision together. Explain the mating components and the intended use where that helps the supplier assess the requirements.
Agree which surfaces or datums define the measurement and whether the requirement applies before or after finishing. A dimension with no clear measurement basis can be interpreted differently by the designer, manufacturer, and inspector.
Avoid applying the tightest requirement to every feature without a functional reason. If a critical fit cannot be supported by the proposed printed process, discuss a design change or a suitable secondary operation with the supplier before ordering.
Review the complete process
Ask the supplier to assess geometry, orientation, material, cooling, and finishing together. Identify features or shapes that need additional attention, and establish whether a sample or qualification run is appropriate.
Do not assume that a change made to improve nesting leaves dimensional results unchanged. Likewise, confirm the agreed inspection point when a surface treatment may affect the finished dimensions or the measurement method.
Compare MJF and SLS using relevant evidence
A blanket claim that one technology is always more accurate is not a reliable selection method. Compare the actual material and process offerings against the same drawing and acceptance requirements.
Request representative results, the method used to measure them, and the conditions under which they were produced. Check that the evidence relates to the features that matter on your part. Unattributed percentages from unrelated studies should not determine the choice.
Keep the requirement with the order
For service bureaus, critical tolerances can affect review effort, orientation, inspection, and price. Capture them before the quote is accepted and keep the agreed specification available to production.
Phasio's part specification records retain manufacturing information, and its review-required pricing workflow can flag work needing manual attention. Configure that workflow around what your team can confidently offer.
Phasio is software for additive manufacturers. It does not supply the printed part or establish its physical accuracy. Those results must come from the manufacturing and inspection process agreed between the customer and supplier.
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