What works and what doesn’t? That’s why I must experiment. There is no readily available information about materials other than wax for lost “material” casting. From my LWC training I know biological materials have long been used as master material in casting.
My instructor said bugs (insects) and plant material are commonly used. Maybe NOT so common, but it has been done before. I assume with some success. In my classes, a woman used thorns that looked like tiny crosses and it worked for her.
I am giving the casting resin for DLP printing another chance. I have the recommended investment material and a slightly modified burn out schedule with a hold at the 700-degree level before going to 1350 degrees.
I found a report about a jewelry maker using FDM 3D printing using Polylactic Acid (PLA) filament. PLA is a material made from biological and biodegradable materials. I will see for myself how it performs as burn-out model material. I made a simple round finger ring from uncolored PLA and will test how it burns out and the quality of the casting.
I am also running a standard carved wax model in the same firing to see how it behaves with the revised burn out schedule. I don’t expect the pause at 700 degrees to create any issues.
The jewelry making couple (man and wife) using the PLA showed a lot of examples of their work in their webpages. They displayed very primitive looking castings. I don’t know if that was by design and on purpose. It could be an example of the results from using the PLA and FDM type 3D printing. Their quality is definitely not my desire. That’s why I must test on my own.
I am willing to use whatever works. That’s the key, it has to work and not be unpredictable. There is too much time effort involved to have casting fail because of the material used for the masters. Wax is my de-facto standard, so whatever I use must perform at the same level or have some other overwhelming benefit. Failure is not an option! Ha!