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Students invent quieter leaf blower

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Re: Students invent quieter leaf blower

#131

Post by alamortsubite »

chasd00 wrote: post #125
alamortsubite wrote: post #88

Earlier quoted context omitted.

Wow, which cities? I've lived between cities and the sticks in the U.S. almost my entire life and while I've never once heard gunfire in a city, in the country it's a daily routine (occasionally, if rarely, even fully automatic).

I live in oakcliff in Dallas (area SW of downtown but still in Dallas proper). Gunshots every night and automatic weapons fire once a month. Police have completely given up, granted it’s all celebratory and usually not crime related. For example, when the cowboys score a touchdown you’ll hear a burst of gunfire.

If they're only shooting when the Cowboys score, at least they'll save money on ammo.

Re: Students invent quieter leaf blower

#132

Post by alamortsubite »

delichon wrote: post #128
alamortsubite wrote: post #113

Earlier quoted context omitted.

The neighbors in rural places I've lived haven't been terribly well-off, as far as I could tell, but they clearly have had different priorities.

It gets massively cheaper when those priorities include reloading your own ammo. My most well off neighbor is the most prolific shooter I know. He shoots targets almost daily with his .22, and I don't hear it at all from 1/3 mile away. He doesn't use a suppressor, but some kind of quieter round. I guess that means slower.

Besides the caliber, that can also be due to topography and wind.

Re: Students invent quieter leaf blower

#133

Post by jchw »

cooperadymas wrote: post #63
jchw wrote: post #22

Earlier quoted context omitted.

It's probably getting there given what Ego has on offer, but I think until it is downright better in at least some dimensions, it's going to be a hard sell. Right now it seems like it's more expensive, at best similarly powerful, and obviously batteries take time to recharge. I think it's gotta be niche for contractors. That said, given how bad gas lawn equipment is for the air in a locality, maybe regulatory nudges…

As someone who went all in on Ego about 3-4 years ago, let me tell you, the technology is nowhere close to capable enough for even small-time contractors yet. You would need at least 3 batteries per piece of equipment in use at one time in order to not have to spend time idle while a battery recharges ($700-$1000 upfront investment in batteries per piece). The lifespan of those batteries under constant usage would be…

I have all electric lawn equipment as well, though my mower is a Toro. No disagreements that a 13A blower connected to AC will beat the shit out of a battery-powered leaf blower, but I'm sure you do and hopefully did realize that, the math just doesn't work out. The one place the Ego does excel at is stuff like edging and string trimming, where there's not nearly as much power needed. They definitely struggle a bit on things like chainsaws and blowers where more power is just generally better.

The place where it is weakest is probably snow blowing. They now have a 2-stage electric blower, but I am pretty sure it's just nowhere near gas. I live in the midwest in an area where the 1-stage Ego electric blower is already kind of overkill, so that's what I'm running. It has its negatives and positives: it always starts without having to worry about the fuel sitting over the seasons, it's quiet during operation and doesn't pollute, the batteries are always ready since they are on the charge when not in use, and I have enough battery to run it for much longer than needed. That said: the batteries are, indeed, simply too expensive.

I'm surprised the mower sucks, this Toro electric mower feels reasonable compared to anything else I've ever used (granted, I do not have much lawn and have never used any serious mowers. Just your average lawn mowers). I wonder if it's true that all electric mowers suck or maybe it's just that Ego isn't/wasn't doing a good job on mower design.

Re: Students invent quieter leaf blower

#135

Post by astura »

Aurornis wrote: post #40
lowercased wrote: post #15

Won't help much until these are mandated by law, or.. we just wait for a couple generations to die out. There's a section of folks who enjoy loud engines. It's their jam, they love being 'outdoors' with loud gas powered engines, big trucks, riding lawn mowers. It's a fantasy escape world for them. Over time, the next couple generations may hopefully adopt more battery powered outdoor stuff (mowers, blowers, etc) beca…

> There's a section of folks who enjoy loud engines. It's their jam, they love being 'outdoors' with loud gas powered engines, big trucks, riding lawn mowers. It's a fantasy escape world for them. That’s an awfully uncharitable projection. The lawn business people I know would love to adopt full electric fleets of gear. They aren’t sending their teams out with gas engines because it’s a “fantasy escape world”. They d…

>That’s an awfully uncharitable projection.

It's neither uncharitable nor a projection. My dad is one of these - the loudness is entirely the point, by his own admission. He told me this. He intentionally buys the loudest most powerful/obnoxious tools he can rather than the most practical and dicks around with them.

My dad is also the laziest man on the planet and does ZERO housework. He only does lawn work because it's an opportunity for him to play with his toys.

>The lawn business people I know

Nobody's talking about people with lawn businesses. Businesses will want to just get the work done and move onto the next client.

Re: Students invent quieter leaf blower

#136

Post by xxs »

dmd wrote: post #73
kristofferR wrote: post #55

Earlier quoted context omitted.

I don't understand this, isn't most of the noise coming from the air and not the engine in the leaf blowers?

No. Nearly all of it is the engine.

I don't believe that part - the ones shown in the picture/videos are brushless motors, quite efficient (90%) and really silent on their right own.

The noise comes from the need to move air (and the noise is just air waves), along with certain vibrations. A brushless motor is super silent if you exclude the fan(s) cooling it.

Re: Students invent quieter leaf blower

#137

Post by phillipcarter »

rascul wrote: post #82
klankschap wrote: post #54

How about just leaving leaves for what they are. Just leave them and move on with your own life.

Leaves can kill off whatever is growing beneath them and they can pose a safety issue in areas where people walk.

Rakes exist.

It's (often but not always) slower work, but it's quieter.

Re: Students invent quieter leaf blower

#138

Post by anarticle »

WaltPurvis wrote: post #130

Can someone explain to me what "quieter" means in this context and/or how it's calculated? I don't understand what they mean when they say reducing the noise by 2 decibels made it 37% quieter -- it wasn't making only 5 decibels of noise before, was it? >>Their design cuts the most shrill and annoying frequencies by about 12 decibels, which all but removes them, making them 94% quieter. The team reduced the overall le…

Decibels are log scale, reducing by 3db cuts energy by half.

Re: Students invent quieter leaf blower

#139

Post by [deleted] »

lowercased wrote: post #50
Aurornis wrote: post #40

Earlier quoted context omitted.

> There's a section of folks who enjoy loud engines. It's their jam, they love being 'outdoors' with loud gas powered engines, big trucks, riding lawn mowers. It's a fantasy escape world for them. That’s an awfully uncharitable projection. The lawn business people I know would love to adopt full electric fleets of gear. They aren’t sending their teams out with gas engines because it’s a “fantasy escape world”. They d…

You are talking about people working in a business. I'm talking about neighbors living in rural/suburban areas. EDIT: We have a lawn care guy. He does our half acre in under 30 minutes. Our neighbors who do it themselves - same half acre size - typically take 90-120 minutes. They'll just sit on a riding mower and let it idle for minutes, while looking up stuff on their phones. Or let it idle and go inside for a drink…

[deleted]

Re: Students invent quieter leaf blower

#140

Post by gumby »

Leaf blowers are pretty terrible for the yard, so anything that makes them more acceptable will just make things worse.

Bad because they blow away topsoil, leaving a hard pack behind that absorbs little water. Just walking around my neighborhood it’s clear who doesn’t use a leaf blower: the dirt is crumbly and the plant life better. If people have pots as well you can see the difference between the two.

Also bad because they blow away all the decaying leaf matter and bugs from under the bushes, again hardening the soil and losing a;l the advantages of bugs perforating the soil and drawing nutrients below.

Of course you can try to fix this by adding chemicals…ugh

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