Nozzlegate: Bondtech's Soft-Steel INDX Nozzles Trigger Buyer Revolt

Bondtech, maker of the INDX toolchanger kit for the Prusa CORE One+, confirmed that nozzles shipped in the Founders Edition and initial batches are nitrocarburized steel, not the advertised hardened steel. Founder Martin Bondeus told a customer in a support email that machining challenges with the harder material broke cutting tools, so the company sent the treated version "for the time being." The nozzles are still superior to stock brass, but the labeling mismatch has triggered backlash from pre-order buyers.

Bondtech batch-tested the supplied nozzles and found them at 30–32 on the Rockwell C scale. True hardened steel rates 55–60, while standard brass sits under 10. That means the nitrocarburized nozzles will outlast brass on ordinary filaments, but abrasive materials — glass-fiber, carbon-fiber, glow-in-the-dark, metal-filled — will cause "accelerated wear." Users printing those materials will need to swap nozzles sooner than a hardened steel part would require. There is no off-the-shelf replacement for the INDX's bespoke induction-heated nozzle.

Bondtech stated no "concrete solution" exists yet, and manufacturing truly hardened INDX nozzles could take months. The company is not offering compensation until it knows replacement costs, and it requests customers hold off on returning kits and stick to non-abrasive filaments in the meantime. The treated steel nozzles behave well for standard PLA and PETG, but the uncertainty has left Founders Edition owners without a timeline or recourse for abrasive printing.

A Founders Edition buyer going by "Daddie0" built Nozzlegate.com after his return window expired a day after the nozzle news broke. He had already logged two weeks of troubleshooting mid-print crashes and layer shifts on his INDX, finally resolved with a Prusa firmware update. His site argues Bondtech's 90-day warranty misleads consumers by ignoring Sweden's mandatory multi-year protections. He is urging other buyers to push for replacements or refunds based on the de facto defective labeling.

Prusa Research, which collaborated with Bondtech on the INDX kit, was surprised by the nozzle disclosure and plans to issue a formal statement soon. The kit is a collaboration, with the Founders Edition a limited run for early adopters.

Tom's Hardware installed a Founders Edition INDX kit on its previously reviewed Prusa CORE One, spending a weekend setting it up. The resulting INDX printed non-abrasive filaments with excellent quality, indicating the nitrocarburized nozzles are fine for standard use. The tradeoff is that any abrasive-filament workflow is off the table until Bondtech ships hardened replacement nozzles. The kit's bespoke induction-heated nozzle design leaves no interim option beyond waiting.