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Why does it take so long to release black fan versions?

noctua.at

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Re: Why does it take so long to release black fan versions?

#281

Earlier quoted context omitted.

Depending on what printers you have available I'll put in the work to get you a ~0.02mm deviation scan of a blade off a 120mm noctua fan I broke. I expect it to under-perform notably due to the surface texture and the lack of rigidity under load causing contact with the shroud walls at high RPMs, but I wouldn't bet my lunch on it, would be fun to find out.

The texture has substantial chance to actually help. Check golf balls.

It really does not have any chance to help. Golf ball dimples don't like magically make the thing better at air, if they did don't you think you'd see these sorts of features on fans or other airfoils to begin with?

You want dimples to create turbulent air that stays attached for longer, this INCREASES skin friction but since the golf ball is a bluff body it's friction losses are dominated by form drag, not skin friction. Putting dimples on a wing will drastically lower it's lift to drag ratio (which could in some cases be desirable, but it will absolutely not make the wing more efficient).

Of course all of this is moot anyway because the dimples need to be tuned to the Reynolds number you're expecting to operate at. Random surface imperfection wouldn't help even if it could help, which it can't.

Re: Why does it take so long to release black fan versions?

#282

Why would someone want a beige or brown fan? If it is that complicated why not only make black ones?

It's surprising that there's enough of a market for a fan in any alternative color that it's worthwhile to spend this amount of development time on it. There are enough marginal fan purchasers who don't buy the original colored ones and will buy the black one?

Re: Why does it take so long to release black fan versions?

#283
post #27

Earlier quoted context omitted.

Noctua fans have a distinct look, you could say the same about black, if you want to black them out just get a case that hides them since that would look the same.

Who's looking at a damn fan? My lord. This is like caring what colour the filters in my air conditioner are. Idiots will have anything marketed to them.

Which is why they focus on getting a fan out before adding a second color

Re: Why does it take so long to release black fan versions?

#284

Earlier quoted context omitted.

The specific fan in question has a rated max power draw of 1.8 W. In actual deployments it's going to be a lot less since ~nobody is running a noctua fan at 100% speed unconditionally

"In actual deployments it's going to be a lot less since ~nobody is running a noctua fan at 100% speed unconditionally" I run dual 36w Delta fans at 100% in my computer case. I use the outflow as positive pressure forced exhaust for my enclosed CO2 laser, which itself has an ultra-weak venting fan. It isn't that loud. A simple no box does the trick.

which is why you went with Delta and not Nocturna I would think? Deltas are fine in an otherwise noisy environment but they’re misery in say a bedroom at night.

Re: Why does it take so long to release black fan versions?

#285

This is content marketing executed perfectly :) Reading it, I learned something new and interesting and they had an opportunity to show off one of their differentiators against the competition (low leakage flow due to tighter tolerances) and then at the end they casually mention the new product that has just opened for pre-orders.

Exactly this. Most of the time you get poorly researched articles (or nowadays, AI slop) about some topics only very remotely related to what the company actually does.

Here, the article is about something interesting that the company has expertise in (and even "insider info"), shows off that they do serious engineering, and is interesting to the target audience.

If I'm buying a 12V or 5V fan, it'll almost certainly be a Noctua. I don't know if they're the best, but they certainly seem to be among the better brands, and at something like $25 for a fan, they are certainly not overpriced enough to justify the effort of researching something better.

So whoever you are at Noctua, congratulations! This + the 3d model release are likely really paying off.

Re: Why does it take so long to release black fan versions?

#286
post #122

This is a really nice write up. The reason itself — why the delay — is totally within my own speculation, but the sheer quality of the writing dragged me through the whole article. That is something. I think this shows how Noctua value their customers, including myself. I really love how they are nice to their customers — both their products and services — especially because experience like this is getting more and m…

It's refreshing to see something without any AI slop for once. The fact that this aspect is so exciting is so sad.

Re: Why does it take so long to release black fan versions?

#287

Not in the gaming scene at all, but my thoughts were, "Why isn't black the first product developed?" Isn't that a standard, and probably has more consumer interest?

And I don't understand why they can't just mold all the colors in parallel. If brown is in production, why can't they experiment with black at the same time?

Re: Why does it take so long to release black fan versions?

#289
Here is a mirror of the article since the "vercel"(?) anti-human wall is not letting me through, https://archive.is/y5zN1

>Why does it take so long to release black fan versions? 30/04/2026

>People often wonder why the chromax.black versions of our fans take longer to launch after the classic colours. In a nutshell, the reason is that this is less like painting a wooden fence, which is easy, and more like changing the colour of a carbon-fibre Formula 1 part, which requires re-calculating the weight, strength and aerodynamics.

>Before we dive in, we need to understand how PC fans are injection moulded and produced. At its simplest, injection moulding involves melting plastic and forcing it into a steel mould, also called “tooling”, to cool down and harden into a specific shape.

>However, for high-precision engineering, this is less like making ice cubes and more like baking a complex soufflé where every degree of temperature and milligram of ingredients matters. The flow rate, cooling time, and pressure must be perfectly balanced to ensure the plastic crystallises, cools correctly, and holds its structural integrity and dimensional precision. When you introduce a new variable, like colouring pigments, that delicate balance is disrupted.

>While this is generally much less of a problem for fan designs that utilise relatively large tolerances and standard engineering plastics such as fibreglass reinforced PBT or PA, it becomes highly critical when building fans with tighter tolerances using more advanced polymers such as Sterrox® LCP. With our NF-A12x25, NF-A12x25 G2 and NF-A14x25 G2 fans that feature impellers made of this material, we have implemented a tip clearance of only 0.5mm (120mm models) or 0.7mm (140mm models) in order to minimise leak flows through the gap between impeller and frame.

>Achieving such small tip clearances is essentially at the absolute limit of what injection moulding can consistently reproduce. At this extreme tolerance level, even minor process variations and material-related factors, such as the addition of colour pigments, become highly relevant. Their influence on the dimensional precision and stability of the fan blade may be minute, but if the tolerance is only a few tenths of a millimetre, being off by a tenth or two suddenly becomes a problem.

>Colour pigments impact the injection moulding of these high-precision fans because the pigment particles behave like tiny solid fillers inside the melt. Their size, surface area, and thermal behaviour directly influence how the polymer flows into the mould, as well as how it cools and solidifies. Black pigments, which are typically carbon black, behave very differently from the beige or brown metal-oxide pigments used in our standard fans. Carbon black particles are much smaller and have a significantly higher total surface area, resulting in stronger interactions with the polymer melt. While beige and brown metal-oxide pigments are larger and have a weaker effect, carbon black alters the melt viscosity, heat absorption, and crystallisation behaviour more significantly.

>When crafting the very first mould for a new high-performance fan, multiple tuning iterations are required until the geometry, cooling, gating, and moulding parameters are perfectly stabilised. In case we run into severe issues, this may even require starting from scratch. Regardless of whether it’s regular tuning iterations or complete redesigns, these hard-earned lessons feed directly into the design of the new mould for the black version, even though it always has to be further adjusted to account for the different moulding behaviour. Since these tuning iterations and, even more so, the worst case situation where the tooling has to be changed so significantly that it has to be redone from scratch, are time-consuming and costly, creating the toolings for the black versions at the same time as those for the regular versions would introduce significant extra cost and risk. To avoid this, we only initiate the production of the toolings for black versions after the mass production of the beige and brown parts is already running smoothly and stably.

>On top of the complex process of creating and tuning the moulds, our approval and validation process for new fans includes a rigorous, long-term high-temperature test. This ensures that our fans will deliver top-tier performance far beyond their 6-year warranty, but the test alone requires several months to run, with additional time needed for preparation and evaluation. Since this validation process must be repeated for the black versions, it introduces a minimum delay of around 6 months between the release of the brown and beige fans and their chromax.black counterparts. As soon as we have to go through some iterations of mould tuning, the delay will be longer, and if we have to re-run the validation tests, we’re already looking at a minimum delay of 12 months.

>At the time of writing, we’re just about to release the chromax.black version of the NF-A12x25 G2 – around 10 months after the release of the regular beige and brown version. Hopefully, the insights we’ve shared in this post help to explain that this is actually pretty close to as fast as possible.

>PS: We’ve only covered delays that are caused by the tooling creation and validation process in this blog post. However, there is a wide range of other factors such as the availability of other components, production capacity restrictions or logistical issues that can play a role as well. For example, during the three-year gap that we had between the regular and black version of the first-generation NF-A12x25, we were in the midst of the global pandemic and dealing with a highly challenging combination of strong demand, disrupted supply chains and logistical havoc, which caused delays that went far beyond tooling-related issues.

Re: Why does it take so long to release black fan versions?

#290

Earlier quoted context omitted.

Noctua wants their fans to last for many years, spinning at 2K rpm, with heat. Being able to produce something with lower tolerance is one thing. Making it work long term at ~10 m/s and ~200G is another thing. Have you ever been in a car that brakes really hard? You'll move. Now, multiply that force by 100 and you'll get around what the fans must sustain over time.

But that's literally not what the article says. You are talking about the design - Noctua puts 0.5mm because any more and airflow is affected and performance drops. They also use a super duper polymer that mitigates everything you mentioned. The article talks about manufacturing tolerances. > Their influence on the dimensional precision and stability of the fan blade may be minute, but if the tolerance is only a few…

> The article talks about manufacturing tolerances.

As shown by your quotes, the article clearly mentions tip clearance, and not manufacturing tolerances, which you are infering. The article doesn't characterize the thermal expansion the "super polymer" is expected to undergo under normal operating conditions[1]: something Lego doesn't contend with.

All this to say: Lego's manufacturing tolerances alone can't falsify Noctua's claims because they ultimately are different metrics.

1. I imagine the expansion rate of the fan blade radius doesn't correlate linearly with that of the shroud, so the tip clearance changes with temperature. With this constraint, not even Lego could make its manufacturing tolerances equal the fan clearance, which has to be larger if you want the fan to predictably work without jamming over a 40-degree temperature range.

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