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Please don't run them at night to protect animals like hedgehogs and others that are active at night.

Also to protect all those, animals and humans alike, who would like to enjoy a silent night.

I'm assuming (perhaps unreasonably?) that given the suggestion you could run it at night, that it's silent, or near silent?

If that's not the case, GP must be a madman.

Anything having lots of rpm ain't silent. Especially not at night.

So they surely ain't as loud as a combustion lawn mower and are pretty silent in comparison, so maybe you won't notice them in the city with its background noise. But in rural areas I perceive them as noisy even on daylight with normal noise level. And I never saw anyone using them at night - for a reason.

And as for gp .. he is already shadowbanned and you likely cannot see his answer (I have showdead=true). He reacted poorly I think.

Yeah, in that case, this sounds like a horrific idea.

I could hear a neighbours smoke alarm beeping periodically due to low battery the other night and went around to replace the battery for them the next day.

Also, I wasn't aware of the showdead setting (and had no idea about the answer that had been hidden), thanks for the tip.

chrip

There’s a growing discovery on YouTube and TikTok videos, that some people just live like this.

Your brain will completely tune the beeping sound out after a certain point, if it's a thing you notice at all. Similar reason to reversing truck beepers being replaced with ones that produce white (or other coloured) noise, so you don't lose your ability to hear where they are.

It's hard to believe until it happens to you.

Still hasn't happened to me; beeping smoke alarms drive me crazy.

Must depend on the model. I can't hear mine from more than 10 meters away.

At night?

I doubt that. At daylight with normal background noise level, possible.

The modern razor blade based robot mowers are barely audible. Segway claims 58 dBA, for context. Anywhere near a city (which, these smaller robot lawnmowers are really meant for smaller city lawns) is going to have close to that for background noise levels. Maybe it's partially audible if you're standing next to it, but with fencing and some distance between you and your neighbor, you aren't bothering anyone.

Hm. With 58 dBA extra noise in a silent area you can bet, that I will be bothered.

In a loud city where it doesn't matter anyway, yeah well, who cares.

Can only disagree there (I built an OpenMower based on a SA650B), in a rural area, also cannot hear it from about 10m away, even at night. Though I don't run it at night except when it is just finishing up from the afternoon

Either there is a new generation of ultra silent mowers, or we have vastly different hearing levels.

Edit: but I only know of mowers noise level from what I experience walking around, I don't own one, nor did I research that model number. Maybe I will.

Electric motors can run at quite high rpms with lower decibels. Sure not silent but the origin is low enough that at a distance say 25 feet it’s almost silent.

Yea, my neighbors battery powered mower is super quiet. I don't even know when they run it.

Mine is also electric and my wife says (i'm always too close to it) it's easily 4x as loud. Not sure what the difference is.

True, but remember what’s quiet to a human may be quite different to what’s quiet to a hedgehog. When reading about these things it’s surprising how often things that we might not consider - like how vibrations travel though the ground - can confuse wildlife in ways that we might not expect when viewed through an anthropomorphic lens.

Man I'm sorry, while I don't want my mower running over a hedgehog, it's my lawn. If they don't like the noise they can leave lol

> And I never saw anyone using them at night - for a reason.

...how late you were checking?

I can see reason to set them on say 5AM so it finishes before you wake up

you've never been woken up at 5am by a neighbor using some tools?

It probably depends on model, but mine is dead silent (Mammotion Luba 2). However the reason I avoid running it at night is it has a fairly bright headlight, and I worry it might create shadows/light effects in my neighbors house and I know they have little kids.

I have an electric (though not robotic) lawn mower, and it turns out that it's not much quieter than a gas powered one. No engine noise obviously, but the blades spinning and hitting grass still makes a lot of noise (and indeed in my case it turned out to be the vast majority of the noise). So it wouldn't be a very good idea to run your robot lawn mower at night.

This is uninformed - my Navimow is close to silent. It makes a slight clicking/snipping sound as it cuts through grass.

The mechanical components are entirely different, instead of a helicopter-like blade it is a ~silent solid disc with some razor blades on the edges.

Maybe your specific model? I have a Makita electric mower and the difference is night and day. It's very relaxing and I mow with no hearing protection. I've tested to see how far the noise carries and none of my neighbors can even hear it. Meanwhile, I hear gas mowers from my neighbors on all sides and several lots away from me.

Even better is to turn most of your lawn into natural landscape, leaving just the part you want to use for recreation as mowed.

This is highly dependent on where you live and what kind of creatures and insects you will be hosting.

I’m a big fan of natural landscaping, but just letting your grass over grow is not that.

I didn't say "just let it grow over" though. Turn it into natural landscape except the part you need for recreation. In many places people almost never play or sit in their front yard, for example. If you make that a natural landscape you might have to mow it once or less per year depending on what you actually plant.

I mean how fast do these mowers mow? I seriously doubt it's fast enough to run over an animal

I think the concern is animals that hide or sit still when threatened more so than it chasing down a rabbit :p Also, eventually animals would get used to the noise until they get hurt.

It's a nice thought but the reality is that you'll be killing animals no matter what. I have a 48" riding mower and live in a rural area. At first I was really worried about all the field mice, voles, frogs, etc., that I saw running away from the mower. After a while, I realized that no matter how hard I tried, a certain number of them were just going to die. I tend to let my lawn grow fairly tall before cutting, and it's a mix of grasses, clovers, wildflowers and other plants that just grow naturally around here. The downside is that a lot of small animals live in it. I only remember running over one bunny so far, but who knows how many I might not have seen.

At least it's not fawns. Baby deer seem to be a magnet for combines harvesting corn.

The wildlife (like hedgehogs) will feel very audited when they get sliced up by a razorblade, run over, and can barely drag themselves off your lawn to bleed out throughout hours of pain. If they don't bleed out, they often end up mutilated, unable to properly eat, walk, etc.

Nice wildlife auditing. Hedgehogs are endangered in lots of areas of the world. Run your robot lawnmower during the day.

If you don't like that mental image, you should feel for the people working at hedgehog rescues

They're certainly not endangered. They were "Least Concern" up until the last few years but have been reclassified as "Near Threatened" due to greenfield sites turned over to land development fragmenting their habitats. The most likely place a person will see them in 2025 is flattened on a road.

Domestic gardens make up an almost insignificant percentage of their natural habitat in any case, and any sort of HOA or Estate Management scenario would likely make it a violation to rewild a garden sufficient to create an amenable hedgehog habitat.

In short, its the responsibility of land utilised for agriculture - and this is recognised by measures around Europe such as the Eco-Scheme and ACRES (Agri-Climate Rural Environment Scheme) which indirectly support the re-establishment of hedgehog populations.

My dogs will eat them if they get hit. It's not a problem.

Hedgehogs ignore loud moving things going their direction ?

No, but they curl up into a ball to protect themselves. Since they're spiky, that seems to work reasonably well against animals. Less so against blades.

The price still needs to come down for what is effectively a slightly more rugged robot vaccuum. I could buy a used car for that, and have enough left over to make it run reliably.

The quality of cheaper models is not great. I bought two from Einhell (power tool brand like DeWalt in Europe) and they both had to be returned due to motor failures. A replacement motor was €150 - for a €400 robot without battery (it uses their 18V tool batteries which is what appealed to me - easy replacement).

The thing is, they are more than a robot vacuum. They need to be able to:

- deal with rougher, bumpier terrain (friction!)

- do so uphill through uncut grass

- not stall the mowing motor with high grass

- cover a larger area

- be waterproof against rain

All of these points need a lot more power individually, and especially so when taken together (and carrying the weight increase of all those upgrades). It seems reasonable they'd cost at least twice as much for "similar" feature/budget levels. And I think that's pretty much what we're seeing.

My father just picked up a Husqvarna 430x to do his yard, and it's a pretty great piece of equipment. It runs basically around the clock and handles his acre on a hillside with relative ease... It finds a couple of the garden beds a bit tricky to navigate, but that'll be a software issue that likely improves as time goes on.

I’ve been watching the “Lymow One” with great interest because it appears a lot more rugged and it uses actual mower-style blades rather than the rotating-disc-and-razors model. Also claims to be able to take care of 1.7 acres, which is about spot on what I need.

It’s still pretty new though, and it's a kickstarter from a new company so not much trust yet.

Their website lists the X7 as "0.75 acres" - how that relate to the 4acres you got it to do?

How well does it cut 2 acres? how long does it take?