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Students invent quieter leaf blower

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Re: Students invent quieter leaf blower

#221

Post by Joker_vD »

sidewndr46 wrote: post #100
mikeyouse wrote: post #61

Earlier quoted context omitted.

Many affluent areas have already banned gas leaf blowers and it’s incredible how quiet the battery powered replacements are. I was in Palm Springs recently and had nearly walked past a landscaper using one before if occurred to me just how quiet it was - didn’t even interrupt our conversation. I believe it was a Stihl backpack version (maybe https://www.stihlusa.com/products/blowers-and-shredder-vacs/... ) but yeah,…

It isn't so much the noise that bothers me, what I've never understood about leaf blowers is what are they meant to accomplish? When I watch people use them they either blow the leaves into the street or the neighbors yard. What do they think that does? Now on the other hand, I do own a very noisy leaf vacuum. But when I've collected a bag full I can just deposit the leaves in my collection container. They are taken…

Wouldn't letting the leaves to decompose be better for the soil instead of constantly removing them? I mean, the tree supposedly uses the nutrients from the soil to grow those leaves, and if you keep removing them away, at some point the tree will simply starve and die, right?

Re: Students invent quieter leaf blower

#222

Post by toss1 »

gumby wrote: post #140

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 beca…

Yes, it can be a real problem, that over-use. You can also fix this by using judicious aiming and throttle control and still be more efficient and easier on the exosystem vs raking.

But you must first understand the issue and want to solve it. Unfortunately, most people, even "lansdscape pros" do not understand it, or want to take the extra care to do it.

Source: my wife is extremely knowledgeable, educated, and passionate about the plant and soil ecosystems you describe, yet I was able to adjust technique to satisfy her scrutiny in a reasonably short time. You just have to get a clue and want to act on it. And yes, we've both seen more abuse done with a leaf-rake approach too. It's not the tool, it's the user, tho these blower tools make it easier to abuse at scale.

Re: Students invent quieter leaf blower

#223

Post by superultra »

CalRobert wrote: post #145
superultra wrote: post #126

Earlier quoted context omitted.

When we moved into a new in city home a few years ago, I wanted to keep things quiet and electric. I bought a ryobi leaf blower and lawn mower, with four 40v 6.0ah batteries. Our lawn is neither small nor big - not sure on sq ft but it’s far from huge. It takes me about 6-8 gull charges to complete mowing and blowing. Leaf blowing is by far the more energy intensive. During the fall I have to space out the work in or…

For what it's worth, automowers are great. I had a Husqvarna 330X doing .75 acres and was very happy with it. I don't even know how far it got on a charge to be honest, it just charged itself so I never had to worry about it.

Those look amazing. We have a rather long and complicated and hilly lawn and due to trees. Do you think a roomier like the 330x can handle a more complicated lawn layout?

Re: Students invent quieter leaf blower

#224

Post by SV_BubbleTime »

xxs wrote: post #24
planb wrote: post #10

Earlier quoted context omitted.

"Our product takes in a full blow of air and separates it," said team member Leen Alfaoury. "Some of that air comes out as it is, and part of it comes out shifted. The combination of these two sections of the air makes the blower less noisy." Sounds like they created a noise cancellation air channel.

I reread it - it says 40% reduction, that's -7dB... I can believe that part. Edit: checked DCBL772X1 - it's listed 68 dBA - that's not necessarily loud, so if they managed -7dB, massive props to them.

Except it is not.

They claim a 2db reduction overall.

Then they say that is 37% the noise. But it is not.

Human hearing isn’t linear with power.

2db is not the human perceived volume.

The article isn’t light on details - it’s bullshit.

Re: Students invent quieter leaf blower

#226

Post by ajmurmann »

klankschap wrote: post #54

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

Are leaf blowers only a North American thing? When I grew up in Germany I hardly ever saw one. When I moved to the US they were everywhere. Not sure if they became popular around that time or if it's just more common in the US. When and where I grew up everyone also took care of their own garden, so I suspect that played a role as well

Re: Students invent quieter leaf blower

#227

Post by riversflow »

foobarian wrote: post #158

I got an electric leaf blower mostly to avoid the noise and partly to avoid gasoline engine issues (a Kobalt 80V blower). What baffles me is that here the designers had a chance to make something truly quiet but instead they blew it and used a super-high-RPM motor-powered narrow turbine placed inside the pipe. It sounds like a dental drill amplified through a set of loudspeakers. I would kill to get a commercially de…

I have had the twin battery Makita model for several years now. It’s a fabulous tool, basically functions how you describe I believe. Puts out a max of 61db on high. Expensive, but we already have makita tools, and it made a hated chore essentially not exist because its so convenient, fast and easy.

Re: Students invent quieter leaf blower

#228

Post by SV_BubbleTime »

addandsubtract wrote: post #39
xxs wrote: post #6

Unfortunately the article is very poor on details. The sound from the video is insufficient to tell. Personally, I'd be quite excited to see what are the changes engineering wise. I bet it'd make a proper addition to BOLTR. I still can't see how it'd be much quieter, as lots of the noise is just the air moving (and making sound waves), perhaps less vibrations, different frequencies due to different rpm?

I might be going deaf and losing high-pitched frequencies, but I couldn't tell much of a difference in the video example of before/after.

Because it’s 2db overall.

No camera is going to pick that up because no human is going to hear it.

They claim 37% reduction, but that isn’t true for human perceived volume.

Re: Students invent quieter leaf blower

#229

Post by dylan604 »

swayvil wrote: post #202
Mountain_Skies wrote: post #163

Earlier quoted context omitted.

Makes me wonder if they intentionally kept some noise to combat consumer perception that it was weaker than gas models.

Good point. If you want a good accurate model of human psychology, look to world of marketing. There is a similar noise-is-strength in vacuum cleaner sales.

We all know loud pipes save lives, so just think of all of the lives you'd be putting at risk by making quieter anything.

Re: Students invent quieter leaf blower

#230

Post by hyping9 »

prmoustache wrote: post #41

Isn't it called a leaf rake? Frankly I never understood the popularity of leaf blowers to begin with. They are noisy, less effective than a leaf rake and very bad for health and back of the users. It seems they exists only because people are stupid enough to think that something that makes noise and use a lot of energy would necessarily be better.

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