Semi-crazy idea for a specialty filament. fiber-reinforced semi-soluable
Combine fiberglass or carbon-fiber, dipped or rolled in PLA or similar, with PVA, or maybe vinyl, as the primary binding material.
Or, fiberglass or carbon-fiber, dipped or rolled in Nylon, with HIPS as the primary binding material.
The PLA, Vinyl, or Nylon would act as a welding agent for the fiber fill, where it touched other fiber, while the PVA or HIPS could be washed away.
Wood-fill might work without treatment, if the solvent tended to expose the lignin. Like paper. Wood-fill PVA might be usable in this way.
I'm thinking this would be a good way to produce a porous, mostly fiber structure suitable for saturating with the resin of your choice for merging modern FDM manufacture with older fiberglass modeling techniques. Sort of a moldless fiberglass.
Have you seen:
https://www.mark3d.com/en/3d-printing-with-fiber-reinforcement-the-continuous-fibers/
Cheerio,
RE: Semi-crazy idea for a specialty filament. fiber-reinforced semi-soluable
No, but I have seen many references to fiber-reinforced filament elsewhere, along with warnings about how quickly they eat nozzles. I've not tried any, and don't intend to until I've purchased a tungsten nozzle.
I'm talking about a potential way to repurpose the fiber reinforcement, that is already put in some filaments, for another, older, form of model building. Wash out most of the plastic and leave a sponge-like lattice ready to take a different type of aggregate. It'd still be weak along Z layers, but probably not as weak, as the resin was allowed to cure, and polymerize, along the Z axis as well.
Of course, simpler would probably be to print a negative mold, wax it or apply some other release agent, throw your fill in that, and pour the resin just like they've been doing for decades.
Frankly, what they show in that website looks like it could be achieved using regular, fiber reinforced filament, in a regularly sliced model, since the outside parameter will be "continuous" anyway. It could probably be done the way they show in Prusaslicer, using an MMU2, by simply telling it to print the fill using a different nozzle, so the entire outside was fiber reinforced but the core wasn't, although, except for price, I don't know why you'd want to.
The more I think of it, though, it might be as good to do it with the filaments that are already available, like a glass or carbon reinforced nylon, and choose something like gyroid, or some other infill that can be filled by pouring, and a nylon-based resin to pour into it. Save the washing step and apply the resin in a single pour with a traditional chemical hardener.