3DP MFG

Quality Assurance

How 3DP MFG upholds the quality process.

We’ve developed a comprehensive set of processes to ensure that every custom part you order adheres to the highest manufacturing standards. During and after production, we conduct dimensional and visual inspections of each order to deliver your custom components on time and precisely as per your specifications.

Inspection Standards

We carry visual and dimensional inspections prior to order shipping. We use standard defect books and inspection criteria that help us to get a consistent level of control, whenever the order is produced. 

Defects are described with pictures, as well as level of defect (which are linked to AQL levels for inspection purposes).

We describe defects with 5 properties:

  • Category: Surface finishes, Tolerances & dimensions, Materials, Parts finishing & Cleaning, Packaging.
  • Name: description of the defect
  • Level: criticality of the defect
  • Bad photo: example of the defect
  • Good photo: example of an acceptable part

A defect is a discrepancy between a parts technical requirements and/or customer specifications.

  • Minor defects usually have a slight impact on the appearance of parts, but they rarely affect their usability.
  • Major defects are more severe defects that can impair the functionality of parts.
  • Critical defects affect part usability and could lead to harmful situations if used improperly.


In case parts are non conforming to Customer specification and/or technical requirements, the inspection results are passed along to the customer for a potential disposition. (The customer owns the part design and its intended usage)

Dimensional Accuracy

For every line item of an order the 3 dimensions of the bounding box are measured on the parts using a Digital Caliper. If the dimensions of the part in question do not fall within the defined tolerances specified of the additive process in question, the part is rejected and reprinted. In case this results in a delay, the production team will send this information to the customer for review and a decision. 

If one or more line items within one order have a higher quantity, it is required to do sample measurements. The sample size is determined by the General Inspection Level II, from ISO 2859-1, depending on the number of units.

General rules

  • FDM: Dimensional accuracy of ± 0.5% with a lower limit of ± 0.5 mm (± 0.020")
  • FDM: All parts are printed with 3 outline/perimeter shells or a wall thickness of 1.2 mm.
  • FDM: Top and bottom layers need to have a minimum thickness of 0.6 mm (6 layers at 100 um)
  • SLS: Dimensional accuracy of ± 0.3% with a lower limit of ± 0.3 mm (± 0.0118")
  • SLS: All unfused powder should will be removed via bead blasting (first) and air blasted (second). 
  • SLS: Air pressure range of 2-5 bar or 29 - 72.5 psi
  • SLS: Glass beads with a diameter of 70-110 micron
  • SLS: If the parts have fine details, the lowest pressure settings are used to avoid damaging the part.
  • SLS: No additional post-processing are applied to the parts unless listed on the PO.

 

Cosmetic Standards

FDM: For all FDM materials, all surfaces will have a consistent visual appearance. Support structures (where applicable) will be removed, and all excess support or build material will be cleaned. To ensure consistency in larger quantities, all parts are printed on the same machine if possible. E.g., printing 5 parts on a glass bed and 5 parts on a textured bed would result in undesirable visual differences.

SLS: Manufacturing partners make sure not to apply any post-processing besides powder removal.