[rao-v]

I think the way this works is with an internal structure, that houses the plastic and is expected to deform, printed first (so it cools), then outer walls with perhaps some air gaping for insulation, then injection into the inner structure at the lowest temp possible, then the next level starts.

Would print slow but might be genuinely strong vs normal infill + many walls (weight for weight).

Multi head printers like the U1 or H2D could do even better with high heat deflection temp plastics like carbon ASA or nylon for the inner structure and outer walls and strong low temp PLA for the injection.

[protocolture]

Yeah I was thinking multi head for this, wider nozzle for dropping material in the gaps. Especially if you could find something lower temp than the other walls.

That said, maybe an acetone drip or something in a strength channel to try and bond it.

Actually what I do (and I think is pretty common) is just stopping the print from time to time and filling the outer infill channels with wood glue and sand. Sometimes wooden sticks.