Here are some points that must be considered:

- Type of printing technology (narrow down this multiplicity to where and how this will be used), eg: FDM for Fast Prototyping or SLS for end-use manufacture

- Process control conditions (specific part specifications, temperature conditions [while printing & cool rate] and post-processing)

- Printing material (different specifications) eg: ULTEM 9085 

- Certification of parts (test specimens, traceability, conformity, standards [ASTM & ISO)  

The key point is the Certification of parts i.e. qualifying them for their intended purpose, this is a by-product of the aforementioned points. The large proportion of dubiety is centred around quality and variability/consistency in the mechanical properties of parts. The dependency on these attributes is imperative for critical end-use applications to see the extension of  wide-spread 3D printing with the same credibility and assurance as other manufacturing processes, eg: injection moulding.

Agreed. Process certification and feedstock and manufactured part certification is still not fully mature. The ability to make structural parts to aerospace requirements is only just emerging

Thanks.

Building on the point of certification, there are already myriad certification schemas.  What is needed for this concern to be eased?

Thanks.

Building on the point of certification, there are already myriad certification schemas.  What is needed for this concern to be eased?

there are already myriad certification schemas.  What is needed for this concern to be eased?

It's often said (rather tongue in cheek) that the nice thing about standards is that there are so many to choose from... more seriously though, if there is a need for a 2nd or 3rd or 4th standard or certification system then an independent outside observe might suspect that the 1st (and 2nd and 3rd) weren't entirely up to the job. Confidence in the 4th of a similar ilk might not be high either.

  - Andy.

there are already myriad certification schemas.  What is needed for this concern to be eased?

It's often said (rather tongue in cheek) that the nice thing about standards is that there are so many to choose from... more seriously though, if there is a need for a 2nd or 3rd or 4th standard or certification system then an independent outside observe might suspect that the 1st (and 2nd and 3rd) weren't entirely up to the job. Confidence in the 4th of a similar ilk might not be high either.

  - Andy.