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Need advice - Need laser to burn top of trees (a bit geeky)

HansJensen

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Oct 19, 2020
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I have a bunch of trees (small ones) which grows every year. I am tired of cutting the tops, as they will grow back. Good for my health, but I rather go to the gym.

So I wonder if I can use a laser to cut these straight. I could automate this by mounting it on my house.

I love automation and if a laser can burn a hole in paper/carton, then it could easily burn off the top of these trees.

I have never used a laser before, but I have done some research.
Most trees are about 32 feet from the wall of my house, but some are a bit closer and some are a bit further.

Will I need one that is focussed to infinity?
Will I be needing a blue laser?

What type of laser would you buy? I can invest some money in this, because I am super lazy (and I love automation).
It would improve my smart house :)

Kind regards,
Hans Jensen
 





Joined
Dec 12, 2012
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It is practically impossible/unpractical.
A suitable laser would either be too expensive or take way too long to cut. And additionally there would be problems (safety and legally) with shining a laser into the sky.

Just from a practically perspective, just keep cutting it with a chainsaw or whatever method you are currently using. In this case lasers aren't really the right tool for this job. I would think that it would take much much more time to design a system using lasers than using a traditional method and only produce an equal or worse outcome.
 
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HansJensen

New member
Joined
Oct 19, 2020
Messages
4
Points
3
It is practically impossible/unpractical.
A suitable laser would either be too expensive or take way too long to cut. And additionally there would be problems (safety and legally) with shining a laser into the sky.

Just from a practically perspective, just keep cutting it with a chainsaw or whatever method you are currently using. In this case lasers aren't really the right tool for this job. I would think that it would take much much more time to design a system using lasers than using a traditional method and only produce an equal or worse outcome.
I am just going to trim the branches on top. These are thin (just a few millimeters thick - thinner than a plastic straw).

If I have a normal laser, I believe that I could use a lens to focus the focal point to a certain length (ie. 30 feet).

To test this, I could use a magnifying glass to focus the beam. All it needs to do is to be able to lit a piece of paper, because the top branch is so thin.

The trees are dark brown, so I guess the color is good (because it absorbs the light).

If one can lit paper from 10 feet, I guess you can practically do it from 30 feet as well? The question is to set the focal point correct.

An easier way would be focus to infinity, but I have not come across much information about that.

In this project I will need to do things step by step. First thing is to burn paper from 30 feet.

What laser would you use (where would I buy one - you can maybe advice what supplier to buy from)?

Does any laser come with a lens that can be focussed 30 feet away? Or will I have to try with the magnifying glass first, and then find a suitable lens?

Thanks for all feedback :) I am really new in this game, but I find it very interesting.

Kind regards,
Hans
 
Joined
Apr 6, 2014
Messages
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Just use your hands, Hans.
Forget about lasers.

I'd hate to see you accidentally decapitated just beacuse your smart home thought you were a dead 'beet'.

😂
 

Philipnzw

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May 19, 2019
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As others have said, building such a laser device would be practically impossible, and also a huge safety hazard.

Our forum has had some instances of trolls asking similarly ridiculous questions so yeah I won't go into the reasons why building such a laser is a terrible idea.
Sorry if I'm sounding a little like an ass.
 

HansJensen

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Joined
Oct 19, 2020
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As others have said, building such a laser device would be practically impossible, and also a huge safety hazard.

Our forum has had some instances of trolls asking similarly ridiculous questions so yeah I won't go into the reasons why building such a laser is a terrible idea.
Sorry if I'm sounding a little like an ass.
Hmm.. Yes, you are sounding a bit like an..

I see that alot of people explain how to burn a piece of paper. There are always risk involved with using a laser, but I cannot understand that it's not possible to discuss this (if it's being used in a controlled environment).

Let's just say that you have a piece of paper 30 feet away.

If you have a laser that focus to infinity, wouldn't the beam focus when it hits something? So it won't be dangerous for anything behind the object?

A safer way would be to focus the beam on the exact distance. So if you would pass the beam 10 feet from the laser, it would not even sting. If you are 30 feet (focal point) it would sting (and not cut your head off).

I see that lasers can have a focal point 10 feet away. Isn't it possible to make the focal point be 30 feet away?

I am happy that you guys think about safety, and I do take safety very serious. But things can be done to practically achieve something + keep safe.

If it's practically impossible to make a paper burn at 30 feet with a laser that costs less than 1 000 USD, then I will rest my case. But from my understanding this should be possible. I just need some guidance on what tool will be the best for the job.

It's not like I cannot cut the branches with my own hands, but one would never invent anything if one would just say "well, just do it the old fashion way"..

/Hans
 

Philipnzw

Active member
Joined
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Messages
122
Points
43
Hmm.. Yes, you are sounding a bit like an..

I see that alot of people explain how to burn a piece of paper. There are always risk involved with using a laser, but I cannot understand that it's not possible to discuss this (if it's being used in a controlled environment).

Let's just say that you have a piece of paper 30 feet away.

If you have a laser that focus to infinity, wouldn't the beam focus when it hits something? So it won't be dangerous for anything behind the object?

A safer way would be to focus the beam on the exact distance. So if you would pass the beam 10 feet from the laser, it would not even sting. If you are 30 feet (focal point) it would sting (and not cut your head off).

I see that lasers can have a focal point 10 feet away. Isn't it possible to make the focal point be 30 feet away?

I am happy that you guys think about safety, and I do take safety very serious. But things can be done to practically achieve something + keep safe.

If it's practically impossible to make a paper burn at 30 feet with a laser that costs less than 1 000 USD, then I will rest my case. But from my understanding this should be possible. I just need some guidance on what tool will be the best for the job.

It's not like I cannot cut the branches with my own hands, but one would never invent anything if one would just say "well, just do it the old fashion way"..

/Hans

Once again, my apologies for wording my reply so harshly.

Well here are a few things to consider,

1. The main problem you would encounter if you tried making a laser tree cutter is Power-at-distance. Currently the most powerful single laser diode available is a 7 watt blue laser diode. Sadly, its also the most diverging laser diode available. Meaning, you would have to either use a large collimating lens or beam shaping optics to obtain a small focal point at a distance. Large diameter collimating lens and Cylindrical lens pairs are both costly parts. Implementing those things into your laser would also take a significant amount of time.

2. You could use multiple smaller lasers and try to blast all of them into the branch at once, but you would have to aim and focus each smaller laser unit individually, which takes a long time.

3. You might consider using 100 watt laser diode arrays to overcome the low power issue, but those arrays have piss poor focus, and will not work well at range. Even if good focus can be achieved, you then have to deal with a 100 watt death ray.

4. Yes a laser will diverge and spread out after reaching the focal point, and its true that it will not burn well after the focal point. But any living thing that has eyeballs would probably have their retinas' nuked if they go into the beam of the laser, because the lens in their eyes will act as the collimating lens.

5. Lasers with >5mW of output power can damage eyes. In order to cut branches, you would need at least a couple watts. Any mishaps here and boom, permanent blindness.

6. Its gonna be a lot of trouble if you disturb/accidentally blind some neighbours. All it takes is someone walking into the path of the laser by accident.

7. Law enforcement won't be happy.

Lets just put it this way, is it possible to build the device you proposed? Yes, with a lot of engineering and effort.
There isn't anything wrong with the core concept, but in terms of safety and general practicality, its not quite worth it.
 
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On sale Now the (((( Mucking Foron )))) tree trimming laser system, a 50kw CO2 laser that our installers nail to your roof then run like hell, cash up front only. Buy Today and receive a free high pressure fire extinguisher and a shiny red fire ax......Start something exciting today with a Mucking Foron.

** MF inc. not responsible for runaway fires or arson charges, not meant for actual use, generator sold separately.
 
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Joined
Apr 6, 2014
Messages
2,436
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On sale Now the (((( Mucking Foron )))) tree trimming laser system, a 50kw CO2 laser that our installers nail to your roof then run like hell, cash up front only. Buy Today and receive a free high pressure fire extinguisher and a shiny red fire ax......Start something exciting today with a Mucking Foron.

** MF inc. not responsible for runaway fires or arson charges, not meant for actual use, generator sold separately.

I'm going to quote you Red so it doesn't get deleted

LOL

:LOL: :ROFLMAO:
 
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Apr 2, 2009
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what part of 'impossible' do you not understand.???

You came for advice--it HAS been given .

Shame on you ----if this is some kind of joke..WE do not joke about lasers and safety.
VR
hak
 
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Trussmonkey25........you know it's " tree person ".........but that made me laugh when I read it.
 




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