Looking for intro to 3D  printing filament for RF/Microwave applications - Page 1
Forum section: electronics / general

author: wb0gaz
author_rank: Frequent Contributor
timestamp: October 13, 2025, 01:04:52 am
content: I'm seeking to learn about the intersection of 3D printing filaments and RF/Microwave environments -1. 3D printing filaments that have zero/no RF absorption properties (RF transparency - you could put it in the microwave oven and nothing would happen, for example)2. 3D printing filaments that provide RF reflectivity (=embedded metal particles?)3. Metal coatings that can be applied to 3D printed objects (to provide RF reflectivity/conductivity)(in both cases 2 and 3, idea is that an object (example a waveguide section) could be 3D printed with a filament offering RF reflectivity property or coated/painted after fabrication to achieve same) --- would it be practical to 3D print a waveguide and have it function (or function with limitations?)As I'm starting this survey from scratch, asking here to avoid fully re-inventing the wheel!Thanks

author: scottapotamas
author_rank: Regular Contributor
timestamp: October 13, 2025, 01:15:33 am
content: Don't have direct experience with low-absorption dialectrics for printing, but the nylon/polystyrene adjacent printable materials are probably a good place to start, for things like RF windows in an enclosure etc.On the higher end, some of the sintered ceramic materials are a good bet.There are some materials designed for RF use, but they're resin or sintered (SLS etc) rather than FDM filaments.One example ishttps://rogerscorp.com/advanced-electronics-solutions/radix-printable-dielectricSee,If it's just educational, then looking at the bulk properties of different plastics is a good place to start, then finding similar printable materials to compare against.A quick check showed some papers looking at the permittivity of common printed plastics. Beyond lit-review you'll need to narrow down requirements and likely find/test materials if you're aiming for something specific.

author: wb0gaz
author_rank: Frequent Contributor
timestamp: October 13, 2025, 01:28:43 am
content: Thanks Scott, much appreciate the quick and helpful reply - I'm certainly at the "learning about materials" stage (as a first step towards determining if 3D printing for RF environments is practical, and further, practical on an individual (not corporate) type budget.Dave

author: MarkF
author_rank: Super Contributor
timestamp: October 13, 2025, 01:54:12 am
content: I mainly print in PLA with no RF experience.However, I would think the most common filaments (PLA and PTEG) would be transparent to RF.And, that the carbon fiber filaments would reflect or absorb RF.Have you seen this YouTube channel:https://www.youtube.com/@MachiningandMicrowaves/videosOne of his videos he 3D printed something through a company doing RF work. They may have mentioned the material they were using. I'm thinking it may have been a resin print and not filament. Sorry, I can't point you to the exact video for it.It might be the video titled: "Unveiling the Future of Antennas and RF Lenses using Radix™ 3D printable material!"EDIT - Ah... His channel was previously pointed to.

author: Infraviolet
author_rank: Super Contributor
timestamp: October 13, 2025, 07:32:17 pm
content: Certainly things along the lines of idea 3 probably aren't going to work too well, 3d printed parts inevitably have layer-lines and other surface imperfections, these aren't going to be good for prints which are supposed to approximate a perfect plane/sphere/other-primitive-shape .

author: wb0gaz
author_rank: Frequent Contributor
timestamp: October 13, 2025, 07:40:55 pm
content: Thanks Infraviolet for the observation - that's helpful. Certainly a rough RF surface will be a factor at microwave frequencies...Continuing the slow trudge up the learning curve, so this discussion and the comments so far are very helpful, thank you!

author: rteodor
author_rank: Frequent Contributor
timestamp: October 13, 2025, 07:49:18 pm
content: There were some discussions on electroplating and conductive filaments in this thread:https://www.eevblog.com/forum/rf-microwave/experimenting-with-waveguides-using-the-litevna/msg4652920/#msg4652920

author: wb0gaz
author_rank: Frequent Contributor
timestamp: October 13, 2025, 08:56:31 pm
content: Hello Rteodor,That is really helpful! Although the topic started as LiteVNA, the discussion (many postings) touches on many of the same areas I am interested in (3D printing in RF environment), and mentions "conductive PLA" as well as plating and surface preparation.Much good reading!Very big thank you for providing valuable connection to this topic!Dave