Review: The adjustable Prometheus Hotend V2!

Review: The adjustable Prometheus Hotend V2!

How much configurability does a hotend really need?

Get one here

Hi there! Have you ever thought something like “Man, i wish my 3D printer was just a bit more complex”? Or “I could really use a few extra adjustment knobs for my printer’s hardware!”? Well, no? What, you’re already overwhelmed by all the options you have right now? Okay, bear with me, because today, we’ll take a closer look at the Prometheus hotend, which is more than just a fully configurable hotend. But it’s just that as well.

So yeah, you heard that right, the Prometheus is a hotend that, instead of trying to be as easy to use as possible, goes the exact opposite way and tries to give you the absolute maximum amount of # control over how the hotend is configured. In its basic shape, it is does remind me a lot about the E3D v6, as most all-metal hotends tend to do these days. But instead of going with a discrete heater block, nozzle and heat break, it builds around the combined nozzle and threaded heat break nozzle thingamajig, which basically combines most of the all-metalness into a single part. It screws into the heatsink on one side, which gets countered by an aluminum nut, and then, of course, with an adjustable distance, acts as a heat break before it meets the heater block. And here again, you can use as many or as few aluminum nuts to extend or shorten the effective length of the heated area in the filament path. Having this thing as a single part means that there are no transitions, for example between the heat break and the nozzle, like most other all-metal hotend have, instead it’s a single, continuous tube that has no ridges or anything # like that. Speaking of filament guidance, it does have a bowden coupler, which, again, like the v6, lets you guide the filament all the way from the extruder’s drive gears into the hotend’s stainless steel # nozzle pipe, even if you’re not using a bowden setup. And you should definitely make use of that feature, especially for filaments like Ninjaflex or Nylon.

The heater block uses the exact same clamping mechanism for the thermistor as the v6 does, but instead of the glass fiber sleeving / it only has PTFE sleeving for the thermistor’s legs – which is just fine for regular use, but might be somewhat unhealthy for you if you push the hotend past 250, 260 degrees Celsius where the PTFE starts decomposing into neurotoxins.

Overall, the build quality of the Prometheus is truly impressive. Just alone the bore in the threaded stick, being as long, smooth and, most importantly # straight, is a very nifty machining feature. All the aluminum parts are perfectly machined as well. And details like the super-simple and quiet fan mount round out the entire package.

But of course, what # use would all that machining goodness be if the actual thing didn’t work? Well, ok, first off, it’s of course hard to, like, judge a performance of something that is practically indefinitely configurable, but thankfully, there are a few suggested layouts available online. I picked one that is midway in between what’s recommended for PLA and ABS, since i planned on using both of those and many more plastics, and that meant, again, basically configuring it as an E3D v6. And as logically expected, it worked perfectly fine with every material from ABS, PLA, Taulman Bridge Nylon and even Ninjaflex. None of those plastics ever jammed, which people keep saying can happen with PLA on all-metal hotends, but I’ve yet to experience that myself, and NinjaFlex even printed at very decent speeds of around 30mm/s with 0.2mm layers, which was something i hadn’t seen a hotend pull off before. All these prints were done with absolutely zero calibration coming from my tried-and true v5 or v6 profiles, the one thing i did see was somewhat stronger blobbing with PLA, which is easily fixed with a slight reconfiguration of the hotend and the slicer, and an overall awful print result with Bridge Nylon, but that was expected as i did not / dry that filament at all beforehand. So with all these materials tested, there’s really nothing that stands out as something that would limit the Prometheus’ performance or achievable print quality. I’m # sure there’s still some potential for more quality here / if you take the time to really tune it to your specific filament.

One more test i did was using a Volcano-like setup with a whole bunch of extra aluminum nuts and the 1mm nozzle stick, and that setup, i guess, had somewhat poorer heat distribution [citation needed] in the heater block area than the real deal, but it printed just fine anyways.

Now, essentially, i did all of those prints without ever reconfiguring the hotend at all, which, i guess, speaks to the quality of the suggested layouts, but also means that i didn’t use the core, defining feature of the Prometheus hotend at all. And honestly, i don’t think you’ll be using it that much, either. First of all, if you adjust the length of the drilled twig inside the heatsink, you’ll have to readjust your printer’s Z home position as well, each time, since the hotend actually changes in length each time, and that isn’t something i’m really keen on doing, and secondly, with that goop on the bottom nuts that you’ll inadvertently pick up over time, it’s not going to get any easier to unscrew and readjust them over time. Especially since aluminium likes to set and grip the longer you use it.

So overall, the Prometheus is definitely a very good hotend performance-wise if you just look at it from the boring old, “ok, if i put this one in, is it going to make my prints any better” perspective. And while i would advise against adjusting the hotend configuration unless you’re confident that your hotend is really the limiting factor to your print quality right now, the fact that you # can adjust it should ever need to,_ for example, tame that one exotic filament that you absolutely need to print with / for that one specific reason and nothing else is going to work. Well, then you can start fiddling with the hotend, and i’ve been in situation like that before where i wished my hotend would behave just a tiny bit differently. Though I’m not sure if i would have actually reconfigured my hotend for it. But thankfully, the Prometheus hotend already works really well for all the materials i’ve tested / with the stock setup.

It is available in 1.75mm and 3mm bowden versions, again, you can use either of those with a non-bowden setup as well. It’s 79 US dollars from, which is not cheap, but about in line with what the equivalent E3D costs, still, the Prometheus one-piece nozzles are a bit more expensive at 25 dollars each. They are probably a bit harder to clean than a nozzle that comes out as a single part, but again, ngh, i haven’t had to clean a nozzle in a very, very long time, so i don’t think it’s that much of a deal. And lastly, the drawings for the Prometheus are available as an alibi Creative Commons Attribution Non-commercial Share-alike / license, but as always, copyright doesn’t exactly apply to physical parts anyways.

So there you have it, a solid hotend overall, with the ability to reconfigure it in certain situations. As always, thanks for watching, i’d appreciate it if you’d leave me a like or dislike on this video. Or help support this channel by subscribing, sharing one of my videos or using the ebay or amazon affiliate links from the video’s description – those specifically don’t link to a specific product, because #anything you buy through them gives me a small kickback that i can use to create more exotic content.

Well, i’m going to have some tea now, see you in the next one. Bye!

Music used: Tobu – Reflection