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Posted by mhb 1 day ago

Wax motor(en.wikipedia.org)
385 points | 65 commentspage 2
Fordec 7 hours ago|
Huh. Do these work in a vacuum? Presumably if sealed right? I imagine there's a few space applications, particularly with solar panels.
tesseract 4 hours ago|
Yeah, they are used in space. I don't work directly in this field, but have discussed wax motors with some newspace/smallsat folks, and get the impression they are popular for the same reason nitinol wire actuators are: few moving parts, no rotary bearings, resettable/multi-use unlike pyrotechnic actuators.
rogerdickey 11 hours ago||
Wax elements are also used in thermostatic valves for faucets (to keep faucet temperature constant given variable hot and cold mains): https://rogerdickey.com/the-ideal-faucet/
leoedin 48 minutes ago||
Thermostatic mixers make sense for continuous flow applications - showers, filling a large bathtub for example. But I don't think they make sense for a kitchen tap - where you might be filling a small basin.

The goal is that the water in the basin is the correct temperature, not the stream filling it - which means you need to compensate every time based on how much cold is already there before the hot water arrives. And that varies seasonally.

The time it takes for hot water to arrive tends to be a big proportion of the total time the tap is running, so you actually don't want controlled 40C water once hot water arrives. Perhaps if you had instant hot water, this would be useful.

paradox460 7 hours ago|||
Moen figured out a good enough solution without wax called moentrol

Push/pull adjusts volume, rotation adjusts hot/cold mix

sublinear 11 hours ago||
Hard disagree with that faucet design, but is a neat idea. I like my bathroom faucet as low maintenance as it already is.

The use case for the full unmixed hot tap is hygiene (usually washing face and shaving).

I also don't want any hot water mixed in when I'm washing my hands. The water coming out of the unmixed cold tap indicates the ambient temperature of the pipes. That's a feature, not a bug.

discardable_dan 11 hours ago|||
You should use warm water when you're washing your hands.
sublinear 11 hours ago||
Why?

I'm already upset enough about what the water heater water is doing to my skin and am about to go tankless under my bathroom sink!

That's by far the more practical option anyway if we truly cared about the problem instead of fawning over engineer porn. The problem is solved. This is pointless engagement about temperature preference masquerading as something more interesting.

maxerickson 10 hours ago|||
It used to be public health recommendation (bathrooms in commercial buildings will often only have warm water, for example, because code required it).

There's been studies demonstrating that soap is what matters.

mkmk 10 hours ago|||
Solubility is a function of temperature.
rogerdickey 11 hours ago||||
at least in my home, both the cold and the hot water are very uncomfortable to wash my hands in, but mixing it right takes ~15s every time so i usually just accept the discomfort
lstodd 10 hours ago||
there is this thing named "Single Lever Wash Basin Mixer Tap".
LtdJorge 8 hours ago||
I think it takes time because the hot water line doesn’t immediately return hot water
rotringlvr 8 hours ago|||
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Trace88 7 hours ago||
My old espresso machine had one of these, always amazed by the simplicity and robustness. Low-tech solutions often hit different.
ddlsmurf 9 hours ago||
I got one from a microwave, it opened vents. It is incredibly strong, also, takes soo much power and is so slow - although i suppose near heat it must work great.
razorbeamz 9 hours ago||
Isn't this more like a solenoid than a motor?
rotringlvr 8 hours ago|
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moron4hire 13 hours ago||
Objects like this make me think of grimdark (steam|diesel)punk works like the video games Dishonored or BioShock. It feels like there's a touch of occultism or corruption whenever one creates a device that exploits analog side effects to create machines in a closed, black-box package.
wvbdmp 13 hours ago||
I see what you mean, but it’s less the exploitation itself than its immediacy and legibility. It doesn’t vanish behind a million abstractions or complicated miniaturization processes but can be readily experienced and understood, like steam.

On the other hand one might as well associate it with “solar punk”, especially when powered by ambient temperature.

bee_rider 12 hours ago||
Yes, it seems generally *punk. It’s funny that steam, diesel, and solar punk have this association with immediacy.

Does the originator, cyberpunk? Lots of cyberpunk stories present us with a society that is dominated by a digital abstraction. But the protagonist is special, so, they might not be.

relaxing 10 hours ago||
I think the “punk” in cyberpunk was about the AI having a gritty, streetwise protagonist to enable it/fight against it. Extremely immediate.
WJW 13 hours ago|||
I have bad news to tell you about your "digital" computer.
quickthrowman 13 hours ago||
> Objects like this make me think of grimdark (steam|diesel)punk works like the video games Dishonored or BioShock. It feels like there's a touch of occultism or corruption whenever one creates a device that exploits analog side effects to create machines in a closed, black-box package.

The second sentence also fits for field effect transistors and solid state electronics in general.

In the spirit of grimdark steampunk, have you ever heard of pneumatic logic? I still see these systems operating normally in some older mechanical rooms, it’s cool to see them still working after 40-50 years.

https://en.wikipedia.org/wiki/Pneumatic_circuit

post_break 12 hours ago||
My mini truck uses a couple of these with vacuum lines to control the choke and EGR. They are expensive to replace for obvious reasons.
WJW 12 hours ago|
Why is this obvious? Beeswax is not particularly expensive I think?
monocasa 12 hours ago||
Because they're not being manufactured much anymore.
ck2 12 hours ago||
now go blow your mind with the first known conversion of electrical to mechanical energy via "Franklin Bells"

TWO HUNDRED SEVENTY FIVE years ago

in 1752, wow

(but they had no idea why it worked)

* https://en.wikipedia.org/wiki/Franklin_bells

Before the storm, the device would ring to remind Franklin, who had been obsessed with the study of lightning, urging him to chase the lightning

ha "chase the lightning" needs to be a catchphrase

BobbyTables2 6 hours ago|
We’ll circle back, launch our go to market strategy, and chase the lightning for a win…
IshKebab 13 hours ago||
I once had an interview at PA consulting where they asked one of those questions where they have "the answer" but their question isn't well specified enough to lead to that unique answer. They kept adding conditions, but I hadn't ever heard of wax actuators before. (I was like 19 or something - didn't get that job!)
phyzome 7 hours ago|
...what is the point of starting this post with an egregious slop image?
cwillu 1 hour ago||
Did you post this on the wrong link? The first image is literally just a photo of a part, you can look up the part number.
fourthark 6 hours ago||
The Wikipedia page?