Prusa INDX Upgrade Kits Slip to Mid-August Amid Ongoing Bondtech ‘Nozzlegate’ Issue
The issue with Bondtech’s hard-but-not-hard-enough nozzles for its INDX system issue has officially impacted the shipping of regular Prusa INDX conversion kits for the Core One+, with Prusa committing to as-yet unspecified material freebies for affected purchases.
Social media spaces have been waspishly buzzing the last couple of weeks, as news broke that things weren’t all they seemed with the Bondtech INDX Founder’s Edition. The short of it is the INDX was initially sold as highly abrasive-resistant with hardened nozzles, but the nozzles that shipped didn’t match the description.
To recap, in 2025 Bondtech announced a next-gen toolchanging system that introduced a dynamic extruder that could pick up and release filament laterally, along with a swappable inductively heated hot end. It generated quite the buzz and has been a long-anticipated hardware release in an increasingly crowded toolchanger space.
Later in 2025, Prusa Research announced it would partner with Bondtech to offer the INDX as an officially supported upgrade for its Core One+ 3D printer. Bondtech would produce the hardware, and would Prusa handle the adaptations, firmware and software changes. The INDX, it would transpire, is Prusa’s gambit on a modern toolchanger, effectively superseding its multi-material unit (MMU3) as the color printing upgrade for its regular desktop machines. (The Prusa XL toolchanger still exists, and while we like it a lot, it’s a behemoth and expensive.)
Crash forward to July, and after delays, Founder’s Edition units – the Bondtech-sold 1,000-unit batch of pre-official Prusa Research upgrades for Core One+ users – officially shipped. All3DP was offered one for testing, but we declined in favor of testing the finalized unit that will be mass.produced later. Founder’s Edition units are, in some minor ways, materially different from what will ship later in the regular kit.
It’s easy to confuse who made what. Bondtech designed and patented the INDX, and builds it. As a part of its partnership with Prusa, it sold and fulfilled the about 1,000 unit Founder’s Edition, which is compatible with Prusa’s Core One. Separately, Prusa has a regular INDX upgrade kit for its Core One+ machine, sold via its own webshop. Separately still, Bondtech also recently opened up orders for a batch of developer kits – printer-agnostic INDX units.
On July 3, a “State of INDX” post on the Prusa blog reported Founder’s Edition units out in the wild and standard kits on track to leave the factory by month’s end.
Two weeks later, screenshots of amended product descriptions on the Bondtech website that remove mention of INDX nozzles being “hardened” began to circulate, amid dramatic claims of a “bait and switch” and pastes of support messages from the company admitting it had not been able to successfully produce a hardened nozzle to the performance advertised.
The nozzles that shipped with Founder’s Edition units, and soon to follow in Prusa’s regular INDX kits, are “nitrocarburized steel” – surface-treated, but not a “hardened” steel nozzle as the name typically implies. The company confirmed this in a post on July 29, explaining its intention to produce nozzles that matched the description of the INDX’s performance as sold, failure to do so, and lapse in communicating the change to its customers.
Bondtech’s own published figures put the shipped parts at roughly 30-32 on the Rockwell hardness scale (HRC) against 55-60 for genuinely hardened steel. A surface-treated nozzle behaves like a hardened one until the coating wears through, which, it transpires, doesn’t take all that much. Bondtech’s revised guidance basically rules out glass-fiber, carbon-fiber, metal-filled and glow-in-the-dark filaments.
Prusa’s communications on this give a mixed picture, confirming the lack of abrasive resistance, particularly with its ultra-abrasive Ultraglow PLA. It claims just 100 g of this material ruined a nozzle. Conversely, it found “little to no wear” across multiple machines that each printed 5 kg of PETG-CF. For affected owners, understanding the abrasiveness of the materials you use is very important now.
What is Bondtech (and, consequently, Prusa) doing about it? The last official note from Bondtech is the July 29 blog post, which closes out on a frank assessment of its situation – that the company don’t know how exactly the situation will resolve.
It explains: “We want to be honest with you: right now, we don’t have a concrete solution ready. We won’t promise dates or pricing that we can’t back up.“ It continues, “a truly hardened INDX nozzle is still a long way from serial production.” With that said, even the regular nozzles could be the cause of a bottleneck, with Prusa acknowledging in a post of its own that they’re in slow supply.
Bondtech notes that “returning the INDX and getting a refund is, of course, an option,” though its preferred path is for folks to hold onto their INDX units and have the performance ceiling from hardened nozzles follow later. The choice to do so is stacked somewhat unfairly on the user, since returning the INDX for a full refund would, in the case of users who have already installed their kit would have to undo the 5-6 hours of intrusive build work required to install it. Labor costs are not covered with refunds.
For its part, Prusa outlines its current offer to those who ordered its standard INDX upgrade kit for the Core One+. Emailed to customers with active INDX kit orders and posted to the r/Prusa3D subreddit on July 31 for posterity, it explains:
- Shipping is delayed to mid-August while it waits for Bondtech to finalize its compensation plan.
- The first batch of INDX kit orders may not all ship in August due to limited nozzle supply from Bondtech.
- Prusa will ship “additional hardware for the initial batch [of] Prusa INDX conversion kit orders.”
- Orders can still be cancelled before shipment at no cost.
What exactly additional hardware means in this situation is still unclear. If the nozzles are already in short supply as Bondtech struggles to make enough of them, then bundling additional nozzles as compensation will surely push back the delivery of other INDX upgrade kit orders.
The situation has put Bondtech uncomfortably under the spotlight and highlighted a strange discord between the two companies. For a product as pivotal to its machines as the INDX seemingly is, “nozzlegate” appears to have caught Prusa completely off-guard.
Whatever comes next with regards to Bondtech-made nozzles, it may not be too long before more options open up. E3D has potentially stepped into the breach, announcing it is working with Bondtech on E3D-made nozzles for INDX.
More news
License: The text of "Prusa INDX Upgrade Kits Slip to Mid-August Amid Ongoing Bondtech ‘Nozzlegate’ Issue" by All3DP is licensed under a Creative Commons Attribution 4.0 International License.