Summary of Do you even need threaded inserts? Strength tested!

Product Review Summary: Threaded Inserts for 3D printing

Main Features:

Types of Inserts Tested:
- CNC Kitchen threaded inserts (high-quality, lead-free).
- AliExpress threaded inserts (similar to CNC Kitchen but potentially lower quality).
- Injection molding inserts (not designed for 3D printing, but tested).
- Thread adapters for converting between different screw sizes.
Installation:
- Inserts designed for 3D printing have a guide sleeve for easier installation.
- Injection molding inserts lack this feature, making installation less user-friendly.

Pros:

CNC Kitchen Inserts: High quality, aesthetically pleasing, and lead-free.
AliExpress Inserts: More affordable than Western options, although potentially of lower quality.
Injection molding inserts: Surprisingly effective in terms of strength, comparable to higher-end options.
Thread adapters: Easy to use, allowing for compatibility between different screw sizes without additional tools.

Cons:

AliExpress Inserts: May contain lead alloys; appearance is less polished.
Injection molding inserts: Not designed for post-installation use; can push material out of the way during installation.
Tapping Threads: Tapping into printed parts can weaken the structure and is generally not recommended.

User Experience:

The reviewer found the installation of CNC Kitchen inserts satisfying, while the Injection molding inserts were more cumbersome. printed threads were noted as a free option but generally weaker than inserts. The testing revealed that the printed part itself often failed before the insert did, indicating that the strength of the printed part is crucial.

Comparisons Made:

Threaded Inserts vs. printed threads: printed threads are easier to implement but weaker than threaded inserts.
CNC Kitchen vs. AliExpress Inserts: Both performed similarly in strength tests, but CNC Kitchen inserts are more reliable and better quality.
Threaded Inserts vs. Tapped Threads: Tapped threads are not recommended due to the risk of damaging the printed part.

Ratings/Performance:

None of the threaded inserts reached the full nominal strength required for the screws used in the tests, with performance at approximately 1/5th of the expected strength.

Overall Recommendation:

Threaded inserts are a beneficial addition to 3D printed parts, especially for applications requiring stronger connections. The CNC Kitchen inserts are recommended for their quality, while the Injection molding inserts provide a cost-effective alternative. However, users should be cautious with tapped threads due to their potential to weaken printed parts. The reviewer suggests further testing with a variety of materials and infill options to optimize strength.

Unique Points Mentioned:

The importance of matching materials to avoid weak points in connections.
The effectiveness of staggered infill to improve bond strength.
The potential for printed threads to be a viable option if larger screws are used.
Consideration of lead content in cheaper inserts as a health factor.

Speaker Contributions:

The main speaker provided detailed insights on the performance and characteristics of each insert type, along with personal experiences during testing.
References to Stefan from CNC Kitchen were made regarding the quality of his inserts.

Notable Quotes

— 13:19 — « The weak spot was not how well our threaded insert meshed with our printed part but the printed part itself on the interface between the infill and the perimeters. »

— 15:24 — « What is a much better alternative though is printed threads. »

— 17:42 — « These are also a very good option and they require no extra tools to install. »