The Prusa Core One+ INDX adds eight independent extruders to Prusa’s Core One FDM printer — hence INDX — promising multi-material and multi-colour printing with almost no purge waste. The claimed figure is 0.013 grams of purge waste per colour or material change, with dual-gear Bondtech extruders.
Thomas Sanladerer tested it and found a lot wrong.
Sanladerer’s full testing.
Why 0.013 g is the number worth caring about
Purge waste is the reason multi-material FDM has stayed niche. Every time a single-nozzle multi-material printer changes filament it has to flush the old material through the hot end, and the waste is measured in grams per change — a few grams, hundreds of times, across a print. A multi-colour model routinely produces more waste than object.
Eight independent extruders removes the flush entirely, because there is nothing to purge: each material has its own path. 0.013 g per change is effectively zero, and if it holds it is the thing that makes multi-material printing ordinary rather than an indulgence.
Which is what makes the rest of this frustrating.
The calibration problem
The mandatory calibration sequence that runs when you start a print is designed to work only with Prusa’s own filament and its specific material properties.
Sanladerer could not print with Voxel PLA until he manually removed the calibration sequence from the g-code. Having done that, he found the entire print sequence uses Prusa’s filament presets anyway, and the print failed.
And the detail that turns an annoyance into a design fault: the results of manual calibration are not saved, despite the display claiming they are — which makes the start-of-print calibration unavoidable in practice.
That combination is worth naming precisely. It is not that third-party filament is unsupported; it is that the machine’s required startup routine assumes one supplier’s materials, cannot be legitimately skipped, and silently discards the manual alternative. Whether or not it was intended as a lock-in, it functions as one — on a platform whose entire reputation was built on openness.
The camera is now pointing at the hardware
A smaller issue with a disproportionate effect on using the thing: the camera’s position is useless, blocked off by the INDX hardware, and manual peeking into the print chamber is heavily obscured by the contraption holding the extruders.
Sanladerer’s point is that this makes checking whether filament has loaded correctly borderline impossible. On a printer with eight independent filament paths, verifying loading is the single most common thing you would want to look at, and the upgrade removes both ways of doing it.
Where it leaves the machine
Against Bambu Lab’s H2C, Snapmaker’s U1, and Prusa’s own XL toolchanger, Sanladerer’s verdict is unambiguous: in his comparison between the XL and the Core One+ INDX, the XL simply works, while the INDX struggles even with some Prusa filaments.
For anyone making things rather than reviewing printers, that is the operative sentence. The XL is Prusa’s existing answer to multi-material and it is a true toolchanger; the INDX is an upgrade to a cheaper platform that currently does not clear the bar its own stablemate already clears.
Worth watching rather than buying. The premise is right — eight paths, no purge is the correct architecture — and calibration behaviour and material presets are firmware, which is the most fixable category of problem on this list. The camera placement is not.