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Rendered at 21:20:25 GMT+0000 (Coordinated Universal Time) with Vercel.
I'm a dev and for the last year I've been working for a company that manufactures pretty complex and advanced machines. I work with proper engineers - electronic, electrical, control, mechanical - and actual scientists. One of the things I've come to appreciate from this is the hidden depts of detail and complexity in so many aspects of the objects that surround us. People work hard on small details that hide in the background but are vital to making things work. And there's often code in everything, all the way down.
And now I can add plastic injection moulding to that. The rabbit hole goes very deep.
Edit to add:
My dad worked forty-plus years as an engineering pattern maker. He made, by hand, the high-tolerance wooden "negatives" that were used to form moulds made from sand and resin. The moulds were used to cast parts for industrial valves: molten brass and gunmetal was poured into them, in a foundry, and left to cool. I think he would have deeply appreciated what this article was saying about craft and engineering and patience.
Also known as "why did China who already owned world manufacturing insisted and struggled on making ballpoint pen until 2017", "why are car manufacturers not making random cheap cars that have the curbs of beloved sports cars", "why are barely 5-6 countries able to make decent jet engines" and all that.
Manufacturing is hard. It's built upon layers and layers of deep knowledge and abilities. And when don't have it or you lose it, just knowing how to make the last layer is not enough, you need to rebuild the entire stack.
Which in this case becomes "painting something black is easy, making a fan black is easy, making a high quality high precision fan black from the starting point of the same fan in another color is an industrial challenge".
We are so used to high quality high precision manufacturing, we have a bazillion factories pumping out millions of very high tech things for random usages or tools now and we stopped noticing it ... And then someone makes a small mistake and you get a "Samsung Note 7 explodes randomly" because of a margin of error small than what our brain can easily comprehend.
(I did a couple months of industrial engineering in university and while it wasn't for me, I loved what I learned about the field)
A lot of times it's cheaper to just full send it than produce a full run at a given quality with a low rejection rate.
The "old" way of making a black fan is you just QC check them, send the good ones to Noctua, send the crappy ones to someone who DGAF because they're putting them some sort of industrial appliance that needs airflow through the box.
Everyone "wins" this way because Noctua gets their fan to spec cheaper and the people building plasma cutters or control units for chemical washers or ATMs get a fan that's "fundamentally good" if sloppily executed and the manufacturer gets less waste. Ain't no different than how the pork belly that doesn't become your bacon becomes dog food and die lubricant.
I suspect this is where a lot of the "X compatible" power tool stuff on Amazon comes from. That and/or the repurposing of "worn out" dies.
Another obvious use case of binning is for microchips where the same die can be "wounded" to create multiple product variants that target different market segments, and also yield improvement from being able to isolate and disable an area of the die that are defective. However improving the manufacturability and yield itself is still fundamentally important
Have you tried Vornado’s alchemy line? I splurged on it due to similar feelings and have been quite pleased. I use the petit as a desk fan.
I would suggest taking that money and buying larger speakers
In any of these categories you can already find some machines are quieter than others despite comparable air flows. So its definitely possible to reduce noise through clever engineering and precision manufacturing.
> Achieving such small tip clearances is essentially at the absolute limit of what injection moulding can consistently reproduce
For folks thinking about Lego tolerances [1] that are an order of magnitude tighter at 10 microns or 0.01 mm, it turns out that the largest Lego moving parts are a turntable at 50mm or so, and rotate at an rpm an order of magnitude slower (100 or so rpm vs 1200 rpm), so these tight clearances (not tolerances [2]) are quite tricky to achieve, and more importantly, maintain over the life of the product, apparently.
[1] https://en.wikipedia.org/wiki/Lego?#Design
[2] changed 'tolerances' to 'clearances' per note below
Clearance in this case is how far away the blades have to be at rest, such that the dynamic forces the blades experience under load won't flex them outwards to the point they scrape against the enclosure. Which I'd assume has far more to do with material properties than it does the raw geometry of the blade.
Now I wish I had a high-speed camera to be able to inspect the dynamic deformation of a noctua fan. I'm curious about how rigidly they behave under load.
I also lament the demise of color coded connectors at the back. I knew to plug my speakers into the green 3.5mm jack. Now everything is black, so I need to look at the manual again to see which of the 5 connectors is the right one.
Back then: I would have loved black-on-black, labelled-in-black, with black cables and and black highlights on a black background. The accessories would be black, too: Black keyboard, black featureless keycaps, black mouse, with a black mousepad, on a black desk, in a black room with black walls and black windows.
Black.
I couldn't get black back then, of course. Computers were beige. The necessary floppy and optical drives were beige. Cables were beige. Keyboards were beige. Motherboards were some moral equivalent to beige. It might be possible to get one or two components in black at some points, but the rest were going to be beige so therefore the whole thing might as well just be resolutely beige.
That really annoyed me.
But I'm not a kid anymore; I'm old. I just want stuff that works well, and that is expandable enough to do some fun and unusual computing stuff with, and that I can see so that when I'm futzing around with it then my job is easier than it would otherwise be.
I don't want RGB or a tempered glass aquarium that shatters when part of it touches a tile floor the wrong way. I don't care about having multiple choices for the color of the anodizing on the heatsinks for the RAM. I don't want water cooling when a big slow-moving fan and some heat pipes does the job very quietly, with improved simplicity therefore longevity. I'm not trying to win a cooling benchmark; I'm just trying to keep the CPU within its specified thermal range while it does work for long periods at its maximum speed. I don't care what color the fans are as long as I can't hear them.
If I want to play with RGB by making or buying some party lights, then I know how to do that. Party lights for the room (or the whole house!), not the guts of the PC. :)
Otherwise: The computer is on the floor under the desk and the USB hub is on top of the desk, and that's all I need to deal with. It is purposeful and functional. There's no style points here, but I just don't care about that anymore.
(I'll be outside yelling at clouds if anyone needs me for anything.)
I have a black case (some 10+ year old Fractal Design model) and an all black keyboard with no labels. Back in the pandemic, I was fortunate enough to score a videocard that happens to be light up RGB unicorn poop. I hate that part about it, so that helps remind me to keep the side panel of the case on. (I could, but I'd rather not disassemble it to unplug the LEDs.)
I always figured white would look better for RGB-lit computers. I don't know why white is so rare.
I have a couple of their screwdrivers too. I'm with with brown.
But whether you love or hate (as I do) the brown Noctua colours, the one thing is that they are kinda polarising. They're not a "clean fit" in any build unless you really wanna show that you use Noctua and use them as a centrepiece. Which I guess is the point of their marketing. They want to make it seem their fans are so good people are willing to put up with the colour.
They are going inside the computer where they aren't visible. The point of a computer to me is to be powerful while being as discrete about it as it can be (i.e. quiet and no blinking rgb lights). I don't have a glass side panel, I run an older Fractal case with aluminum sides with sound dampening instead.
I never understood "form over function", but each to their own.
Speak for yourself :) My computer is pretty open, the fans are visible through the front and through the side panel.
I don't run RGB either though but I do like to style it.
And of course the "form over function" is part of that market niche that really pays a lot for something like a fan. Noctua aren't that special, as others have mentioned there are much cheaper brands with the same performance including sound level. You do pay a lot for just the branding.
I have some Noctua fans still going strong after a decade. Are there other brands that can also do that? Probably, I have some BeQuiet fans now too in a tower CPU cooler (couldn't get hold of a Noctua cooler during the pandemic), it will be interesting to see what happens in another 6 years or so with them.
And no, I don't change my computer every 3 years or so any more, so longevity does matter to me.
I think there might also be export restrictions, but I'm not sure.
>Semple developed a pigment called the "pinkest pink" and specifically made it available to everyone except Anish Kapoor and anyone affiliated with him
Anish seems like a bit of a dick
Just this morning I purchased these car mats for my black, korean-spec-tinted people carrier electric van:
https://carmats.ie/products/kia-pv5-passenger-2026-van-mats?...
I have not really had the chance to properly test range, but it's not going to be amazing. It's reporting about 6.1km/kWh average at the moment, with about 50% motorway driving not really exceeding 110km/h. I'd expect no more than 350km. I rarely drive it 100%-0%, so real world (80-20) is probably 300km max. I might be underestimating the range if I do some math though! I live in Ireland, so that is an absolute massive amount of range for roadtrips. My Kona did about 6.5-7.5 depending on the season.
If you have a family, even a small one, then I reckon this is a no brainer. The price is ridiculous, and in my books it beats out an SUV in almost every category except maybe offroading.
Go test drive one!
Though it's not that likely that users will try to replace the blades on a fan.
This was their response when I asked why: > Yes this policy was put in place because there was multiple instances of people reselling their faulty products after receiving a replacement.
> The secondhand buyers then reached out to us, let down to have received a broken product.
I'd imagine it's a similar reason for Noctua.
White doesn't really look bad in any case (except perhaps a full black one). The brown is very identifiable but that's only really a point if you desire to flaunt your expensive fans. Because it will stand out too much in almost any build. I honestly don't care about that, and for a fan this price I shouldn't have to put up with hidden advertising.
But I have BeQuiet Silent Wings and they're not bad. Quietness isn't something I'm optimising for anyway as I only use my desktop for gaming and when I do I wear headphones anyway. I do want to optimise more for pressure (as I have air filters) but these fans are no worse than Noctua.
https://www.fractal-design.com/products/cases/north/north/ch...
https://www.fractal-design.com/products/cases/north/north/ch...
Still not something I'd buy though.
I like wood but only light wood, not the dark kind. That reminds me way too much of my grandparents' furniture.
That said, I don't want RGB bleed, nor do i want a case where I see the insides. The computer is there to be powerful and discreet (both when it comes to noise and looks).
But sure, you could skip the walnut. I think Noctua should also go well with lighter woods. Oak perhaps but probably not all the way to birch.
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 more scarce. I really appreciate their work.
But I don't think they really need that.
I got really excited for a while, been struggling to find a 3rd party heatsink for a noisy GPU that won't make it even more noisier.
But, seems what you're talking about is this? https://www.tomshardware.com/pc-components/air-cooling/noctu..., which seems to have been just for the GH200 and seems to be more like a "super-cooler", as it's cooling both the CPU and the GPU.
Went to Noctua's website and found no GPU coolers at all, so I think it might have been limited to just showing off at Computex 2024 maybe.
https://www.noctua.at/en/products/asus-geforce-rtx-5080-noct...
That said, on my last PC build I ended up buying Pure Wings 3, which are quite competitively silent at similar airflow and much cheaper.
And white. Because I do like silly pretty PCs, as long as they don't have RGB on.
I suppose we should be somewhat positive that some company still aims to deliver best possible products. Not just products with cheapest possible cost and some perceived luxury if even that.
Also, if their product ever does enshittify, the shit would truly hit the fan.
But for all their tight tolerances and exotic materials and a high price to match, they generally don't outperform BeQuiet's more regular materials but use-focused fans that are half the price. Nor are they significantly better than Arctic's general purpose fans at a quarter the price.
It'd make more sense to just buy the fan optimized for the specific common purpose (airflow or radiator) than pay double for the Noctua for a more generalized fan, but is not the best at either common use case.
Seems like these days their target audience is those who believe their marketing materials about them being the best, instead of believing the benchmark performance data.
I have used Noctua fans in computers where they worked for a decade or so, even 24x7, until an upgrade or replacement of the computer was required by other reasons than because of the fans.
I have also had many problems caused by cheaper fans.
So now I always prefer to use rather expensive fans and power supplies, from brands with which I have accumulated many years of experience, for peace of mind.
Perhaps other brands of fans that nowadays give similar results in benchmarks also have similar reliability, but I am not willing to bet on it.
But my Arctics that was installed in the same case that ran for the same amount of time are still chugging along strong, and those are about as cheap as fans get. Different load/use case though so it's probably not a fair comparison.
These days, I really think the competition has caught up or passed Noctua.
But yes, sometimes up to 5x more than the comparative Arctic in common size categories where it basically trades blows for most metrics that matter. Arctic is seriously unbeatable in value:performance if you just need a basic fan without other QoL or aesthetic features.
120mm is the most competitive category, and it's the most obvious category how Noctua can't keep up with the faster iterating/innovating competition.
In general, yes, Noctua is overpriced and Arctic is an incredible value, but when you want to optimize your silence/performance ratio, it's still Noctua, BeQuiet or (sometimes) Thermalright.
This was a fun revelation when I got into watercooling. You might not hear coil whine over a gpus fans. But remove the fans and put it under load and whoo boy.
So this confuses social media discussions on the topic by mixing together everyone's reports, regardless of their level of acoustic masking. "My card has no whine!" says the guy with three 2000 rpm fans going etc.
Gpu waterblocks seem to be shifting towards fully enclosed "tomb" style and I can't help but wonder if coil whine contributed to that decision.
But on topic, I had seven a12x25 in my last build, two a12 and four a20 in my current build. They are exceptional. A computer is as quiet as it's loudest part. If your care about noise, why would you ever skimp on the moving parts.
Problem becomes worse when the cards are driven harder because there's more cooling capacity from the watercooling in the front, but the passive cooling capacity on the back is still the same.
I used to stick a giant fin block on the back of the card to keep temps there reasonable. I'd love it if actively cooled backplates become the norm for watercooling.
They're not toys. If you stick your finger into one of these it does not peacefully come to a halt, the tip of your finger gets buzzsawed off and then it stops about halfway through your fingernail.
(The i stands for industrial)
They're still really good fans, but a lot of this is just marketing.
At max power the Noctua NF-A12x25 has 56 CFM and 2.3 mmAq for 31dBA [1]. At 70% the Artic A12 Pro is 56 CFM, 4.3 mmAq, and 31dBA [2]. At 60% the Asus ProArt PF120 is 61 CFM, 2.6 mmAq, and 30 dBA [3].
Note that the ProArt is a bit thicker (25 vs 30 mm) and all these dBA numbers are almost certainly unobstructed airflow. The Noctua is certainly good, but it's literally over 5× the price of the Artic.
[1]: https://www.cybenetics.com/evaluations/fans/4/
It’s kind of refreshing to see really.
I still have computers from 2017, with Kaby Lake CPUs, which have been used as servers and in which the Noctua fans work as well as in the first day. Prior to that I had some computers with Noctua fans that had been used for more than a decade without fan problems, and which were upgraded or replaced for reasons unrelated to fans.
Thus the good experience that I had with the reliability of Noctua fans, coupled with some bad experiences with cheaper fans, which had to be replaced prematurely, make me reluctant to experiment now with other brands, which might have the same performance when new, but I could learn about their reliability only after a few years.
I ended up buying Pure Wings as mentioned. Also much cheaper than Noctua and seemingly not having those issues.
Noctua fans are still the top #1 performers in the world. You can argue that it's diminishing returns and you can get a fan with 90% of the performance for 50% of the money, but that doesn't change Noctua's position at the top.
I can put in a few Noctua fans and be confident they are going to last 5+ years of running 24x7. Or I can put in 25% cheaper fans and be pretty much guaranteed one or more is going to fail within the first couple years.
In my opinion, fans are never a place to cheap out when building a PC - server or desktop, whatever.
I love rotary woofers :) I hope to get one some day.
I am running them at about 800rpm and the CPU is usually between 33~37 degrees.
When I rebuild my main PC, I will surely go with them again.
In which case they'd have silent cases with no glass panes, because those are thinner and a possible source of vibration. They may even glue (opaque) sound absorbing material to the inside of their cases.
In which case, who cares what colour the fans are?
My DH-15 isn't particularly silent because the fans are silent but it's so effecient that the fans barely need to spin.
I'd prefer no glass, but nevertheless just bought two glass cases because no alternatives that met my requirements were available:
* Fractal Design Torrent Compact - Best cooling available for a GPU-free, air-cooled CPU system. There exists a non-glass version, but it's unavailable in North America.
* Thermaltake The Tower 300 - Smallest form-factor case that will fit a 420mm AIO cooler. Only available with glass sides.
Not every quiet PC is built in a dense box. Good airflow with big, slow fans is working for me to cool a 9800X3D and a 5070 Ti quietly under load.
The one you linked is all mesh so it doesn't capture noise anywhere. It's great if you like it, but I'd never consider it.
Just want to mention I have no beef or issue with Lego. I say that you get great offerings from other brands as well now.
LEGO issued an official apology and you can get replacements for your brown bricks made before 2018. (=
https://brickshow.com/2018/12/problem-lego-reddish-brown-bri...
Goddamn was I wrong! Their CPU coolers are the most well-designed, thoughtfully planned, amazingly performing consumer product I've seen in a while. 10/10, highly recommend! I'll use them for all PC cooling needs going forward.
Seems like a bit overstated for a CPU fan but I might be wrong
I'm glad companies like Noctua exist that put so much thought and care into their products. I don't even mind being advertisted to when that's the case.
The blades of the fans are fiber-reinforced, in order to have sufficient rigidity, even when very thin.
Only a 3D printer for metals could print something rigid enough, but such a metallic fan would be too heavy for a computer fan.
> To protect our intellectual property, certain features – such as fan impeller geometries – have been slightly modified while remaining visually very close to the actual product.
So you do have to 3d scan them yourself if you're trying to print a copy.
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.
It can very well be like the snake oil which makes you feel better maybe for the three seconds after you bought it. Or those gold plated audio jacks which are 0.0001% improvement in quality.
The black fans are really only needed by those who build show piece in those cases with glass panels, but they might equally well need white fans, which Noctua doesn't make. Personally I don't really care about the colour of my fans, you can't see them anyway.
Apple’s white earphone cables are a classic example. Back in the iPod days everyone could tell who had an iPod versus off brands (many of whom, of course, existed long before iPod).
Enthusiasts care about the details - airflow, cable management and of course aesthetics. Noctua doesn't. I respect their engineering/no bullshit approach, the price bump is worth it but they lost my money on multiple builds by sticking to their 'brand color'.
They're the Soylent of the fan world - everything you need but spark zero joy.
I'd be interested in seeing sales figures for same fans in their brand and other colors.
Idiots will have anything marketed to them.
https://www.topgear.com/car-news/retro/lamborghini-has-resto...
I gave the ducks just two coats of varnish, not three as we usually do!
Source: https://www.lego.com/en-us/history/articles/b-the-beginning-...
You have to redo injection moulds anyway as they have a limited life. And you can do a lot with materials too, some materials simply shrink more than others as they cool down.
The thoroughness & mindset is certainly appreciated, but you can also overdo it - engineer it beyond what the consumers use case requires.
I've got a Noctua NHD14 in my current build that I bought in 2011 and it performs perfectly still (including 2 free socket upgrades from Noctua).
When the additional engineering adds no extra end user value. e.g. You need the blades to be strong enough to not shatter or flex, but beyond some level of strength it adds no additional utility
This mindset I think is why companies tend to favor releasing slightly broken and shit stuff, instead of waiting until they feel like they made something the best it could.
Generally, I think it's not overengineering that's the issue, it's how the consumer need for that particular level of quality/performance is marketed to the wrong audience. Cars are the classic example. Most people who drive a car that was precision engineered for speed or offroading capability rarely if ever need that functionality.
That said, in a world of consumer good racing to the bottom and physical enshittification, I'll generally pick the item that's obviously well designed, even if beyond the capabilities I need. The alternative is often a slew of indistinguishable crap.
>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.
In zie olden PC days™, there weren't many options for quality fans except maybe whatever random fans Delta made that generally weren't optimized for low noise or low power consumption. Ancient, no name sleeve bearing fans would almost always go out within 1-2 years at 24/7 100% duty cycle.
I also don’t really like policing writing style when there aren’t any glaring errors.
I didn't get that at all. Calling out AI for the sake of it is the new virtue signal, unfortunately.
> 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.
and
> this is less like making ice cubes and more like baking a complex soufflé where every degree of temperature and milligram of ingredients matters.
Not a problem, but it felt odd enough that I noticed it, so maybe that's what got them thinking it was AI written/assisted?
> advanced polymers such as Sterrox® LCP
> we have implemented a tip clearance of only 0.5mm (120mm models) or 0.7mm (140mm models)
> Achieving such small tip clearances is essentially at the absolute limit of what injection moulding can consistently reproduce.
Typical tolerances for injection moulding are 0.1mm, or 0.03 for high precision, or even better. LEGO was said to be in the 0.01-0.03mm. So on the face of it the last statement is patently false or at least too generic, injection moulding can consistently do much better than 0.5mm. With standard injection moulding precision (0.1mm) the worst case scenario for the two parts (fan and shroud) mating would still stay comfortably below 0.5mm.
So the question to the experts, is Sterrox® LCP that much harder to work with and the marketing team just didn't understand the importance of being clear about this? Is it a decimal point typo and the numbers should be 0.05 and 0.07?
When very precision molds are made, what Noctua talks about in "multiple tuning iterations are required until the geometry, cooling, gating, and moulding parameters are perfectly stabilised" is the standard process for this type of stuff. (Gears, bottle caps, or any molds than make 8, 16, 32, 64, or 128x of the same part in one shot, require that you start with "steel safe" geometry, meaning you mold the first test parts, measure them, and then modify the mold (by cutting material AWAY, it's very hard, usually bad idea, to add steel back to a mold)).
You can do your best to determine what geometry is "steel safe", and all of this is baked upon having very good engineering understanding of what material you are molding (and using very expensive software like MoldFlow to simulate this).
Legos are made from ABS, there are decades of research and data on how ABS behaves in mold, it's relatively safe to use results from Moldflow and be pretty confident in it. Noctua is using LCP. LCP is very niche, and it sounds like they themselves are doing the research on moldability/warp/process effects. And while also being a company that produces things on timelines, the friction/side effect is that sometimes best guesses will fail and they have to start over with new molds (that's a 2 month hit usually) and months of testing. That is what they were trying so say.
I design glass-filled nylon and polycarbonate parts/assemblies with tolerances 1-5x higher than theirs. The 6-month delay they described is something I've lived through many times when we had to "cut new molds" because we couldn't salvage the first mold. (Advanced molds like these are $50k - $200k+). As a company/designer gets more experience with new materials and colorants (like their stuff with LCP), they will probably be able to hit end-goals on first try more often as they collect learnings from their failures.
Ive recently started messing with the idea of making my own model car kits as a hobby. I understand a lot of the basics, but have never done anything like this before.
Im obviously not going to make kits in mass, but, i plan on doing injection molding using polystyrene. I do not currently have a cnc, but have been eyeing a SainSmart, though they say "can do metal under certain circumstances", but doesnt cover any of those circumstances. I also was looking at various injection machines and the price for entry is insane to me - $1000 for something that would probably burn your house down.
Anyway, to my questions..
1. Suggestions for a hobby cnc that can work aluminum? Id be willing to go as far as $2kUSD, unless theres something more that you think would serve me significantly better 2. Suggestions for a hobby injection machine that can do ~60-100g shots, that wont try to burn my house down, and doesnt cost a ton? 3. Any tips or thoughts for someone diving in to this? 4. Things i should purchase for QoL with cnc or injection molding? 5. Where does one buy materials (in hobby quantity) like aluminum block stock and polystyrene pellets?
On the small CNC that will work with aluminum... There is a whole tradespace around how small of a feature you are trying to mill vs spindle speed vs machine stiffness & spindle runout. If you were to get something like a HASS you can sorta do it all, but when you get into the hobby stuff, you need to be very certain about what smaller set of machining limitations you will be dealing with and if they will still get you where you need to go. You need to work backwards from what actual tolerances you need to hold for the downstream thing to be able to work. (For instance, if you are making an aluminum mold, when you machine it, you will most likely be repositioning the work piece... if your machine isn't square enough so that when you flip the part on it's side or upside down, then do your next op, the part may not have been square to begin with, so now you have something that won't match the other thing you are trying to mate to.)
I build a 2'x5' 3 axis with ATC, starting from a CNCdepot concept and did my own control. I probably spend as much money on precision straight edges, levels, 90deg blocks, lapping tools, etc that were required to build a machine that could hold tolerances to 0.001", which is probably where you need to be landing to have molds that work.
I guess I am just trying to say it's a very big and ugly can of worms you are opening up.
Before buying anything, you might just want to try using firstcut/protolabs. They will machine the aluminum molds and mold the parts for you. Price per part is not going to be pretty, but it's going to be way less than spending thousands on machines that will never get you to where you want to go.
As for "desktop" molding, there is some startup now pushing their kludged together machine, maybe that is the one you are referencing. I'd stay far away from that thing. I think they were charging a couple $k for it, I feel like you need to be at 5x-10x that for anything reasonable. But at that point, the amount of power and infrastructure you need is well outside anything you'd want to put in your house or even garage. Don't really have a good answer for you here.
One thing to look at, if you are doing those model kits where like 20 parts are all in one flat sheet and you twist them to remove them, people are starting to make these on FDM 3D printers, which might be worth looking at. Now you can prototype and do production on the same machine, which at your stage, is the right place to be.
I knew the technology itself can have tight enough tolerances that are not a concern from an engineering perspective when talking about a 0.5-0.7mm clearance, but no details about the challenges of this LCP.
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.
> 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.
> Achieving such small tip clearances is essentially at the absolute limit of what injection moulding can consistently reproduce.
I'm not questioning their engineering but the wording of whoever wrote this article. For anything with a clearance in the tenths of a millimeter, injection moulding doesn't even sweat, let alone be at the limit. Anything better than bog standard injection moulds get you better precision than "a tenth or two" millimeters.
Let me put it another way, if achieving a 0.7mm gap is "at the absolute limit of what injection moulding can consistently reproduce", what would you say consistently achieving 2-10um (microns) gap is? Magic? Fairy tale? Because LEGO as I said earlier is said to have 2um tolerances [1] over their decades of producing the bricks. Even a more conventional 10-20um (order of magnitude higher) still works.
[1] https://news.ycombinator.com/item?id=47335237
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.
Phrased differently: a 0.5mm gap is the minimum possible to also be able to account for the 0.1mm (or whatever) variation in injection molding.
You're right to question the wording.
The Noctua engineers definitely designed the clearances to perfection and accounted for the variation in the manufacturing process, I don't doubt that.
The article says "being off by a tenth or two suddenly becomes a problem", the 0.1mm you also thought of. But that's the point of contention, 0.1mm is the tolerance from bog standard, cheap injection moulding. The limit of consistent precision is in the single digit microns. Noctua doesn't need anything near that.
Unless working with that polymer is difficult and comes with higher tolerances, this is probably just a case of the article's author trying to pump up stats. To bring it more to the techie world, it's something along the lines of "130nm transistors are at the absolute limit of what EUV lithography can consistently achieve".
In their own description of Sterrox® LCP they say it has "extreme tensile strength, exceptionally low thermal expansion coefficient, high environmental inertia and excellent dimensional stability". With such an advanced polymer any deformation in operation has to be a rounding error compared to the manufacturing tolerances.
Noctua's signature... brown-orange? Whatever that color is, it has the same issue. The blades are basically gray if I don't wipe them.
Haven't seen anybody start a gray craze, though. Though I have a grayish motorbike that also shows dust and dirt like nobody's business (it's a bike I use strictly on paved roads).
What is it you think they're doing wrong?
Does another vendor satisfy your criticisms?
Why do you think they don't optimize for things like performance when they often win performance competitions against other vendors for both sound mitigation and airflow?
Do you know they have a specific high efficiency line?
Have you ever had a noctua fan fail where you think another vendor fan would not have?
I don't think matte white is worse than matte black in terms of showing dust. They both do.
If you need daily dust cleaning you should invest in a room air filter.
I don't understand why anyone would think this is an obsession with black.
Not much real research into that topic, interestingly.
[1] https://medium.com/@pueojit/a-look-into-the-yellowing-and-de...
The people demanding black versions of their fans for their color matched builds already know they’re the best fans in their class.
Granted, there may be other places in which the molding precision may matter, which would make this an impractical solution.
Noctua talks about it on this page: https://www.noctua.at/en/expertise/tech/sterroxr-liquid-crys...
Even if it is the case, and not simple an omission to focus the narrative, does it matter? Case fans pull what 4 watts? 5 watts? Who cares if it pulls 200 milliwatts more than a competitor when it's cooling a GPU and CPU that consume more than a hundred times what it can consume
That's really high. Like usually they are 100-150mA (so sub 2W) Lots of controllers would be 1A max.
The tolerances are for noise mostly. I'd consider the noise (and longevity) the single most important part of fans (else most fans can spin close to 3k rpm and cool)
1: https://support.apple.com/en-us/103253
Transcoding multiple video streams, running a VM and running various other tasks, mine rarely passes 10, and is currently sitting at 7 (only 2 transcodes at this time).
It’s 30 day average is 5.
One is heat, heat is not great, it puts more stress on components, mechanical and electrical, reducing longevity.
Another, maybe more important is noise. The power that goes into making noise is power that is wasted, noise is inefficiency, and reducing noise is an efficiency problem.
They go above and beyond.
I thought the primary gain in efficiency came from the large blades, with the blade shape the next most important factor. Gaps between the blade and housing feels like a single-digit percent effect.
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.
Yes, exactly. The high precision is marketing, not something needed in the product.
FWIW, in my setup (10th gen i5, RTX 5070 Ti in an old Define R3 case), the 12 cm Noctua G2 fans run quieter and have a much less obnoxious noise than the old P/F series, which wipe the floor with the Arctic fan I bought for a computer that lives in the basement and sounds like it's about to take off.
They do have the most insane pricing. I could see myself buying some in the 15€ range but not 35€.
A lot of Noctua sales come from their brand value. People put Noctua fans into their gaming PC's, use headphones while gaming on them, and then turn off the PC. You don't really need the most silent fan for that, but people buy them anyway for the looks & premium quality.
I do love Noctua's coolers though, I appreciate the well thought design, manuals and free upgrade kits when you upgrade your system to a new socket type. But for case fans I'll jut buy Arctic and save money, except for things like server systems that run 24/7 in my bedroom where noise and durability are top priority.
... which is why I only have a few of them, rather than replacing the fans in everything I own. But for the things that need them, there's just nothing else as good.
This is an enthusiast product, as evidenced by the premise that you care about color-coordinating the inside of your computer.
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.
We have a few hundred of their coolers in use and I have never had an issue getting warranty replacements from them with fans. The process is simple and they ship out a new fan ( I have warrantied probably 10 - 15 of the fans)
In this case, I finally understand why they chose their most iconic colors, and appreciate the time they take on precision engineering.
They also utilize different manufactures afaik (historically Taiwan, but also China these days) meaning they need to have pretty solid in house knowledge and expertise to make sure different factories produces similar results. When they first started utilizing Chinese factories people noticed visual differences and were worried about that. But Noctua at the time claimed that they made sure that performance was still the same. A claim that was put to the test by various review outlets at the time (I want to say gamer nexus did a big piece about it?) and confirmed to be true.
Having said that, if you do utilize external factories you automatically are making use of their process engineering to some degree as well. But, and this is difficult for many people to understand, that isn't a binary thing either. You can entirely rely on the factory to basically do everything for you and just send feedback on iterations but you can also work closely with them and actually get involved in the process itself.
If you want top class injection molding tooling / machines or process you are probably going to contract a Chinese company to do it.