Laser Cutting Head
Posted by aka47
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Re: Laser Cutting Head December 30, 2010 04:42PM |
... thanks for the link!
I have only 4 of the plates, so not enough for an enclosure, but enough for some goggles.
When testing with them i can't see any blue transmission, but i can see the spot in orange, so i'll estimate an absorption of maybe 98% of the blue light at 445nm and full transmission of the glowing, what's not so bad
This plates were samples of UV-shielding for photochemical PCB-generation, so 100%-blockers for UV and blue.
When pointing with the laser through the plate directly, it blocks the beam completelly and melts/burns away slowly, so the shielding effect is more absorption than diffuse reflection ...
Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]
Call for the project "garbage-free seas" - [reprap.org]
I have only 4 of the plates, so not enough for an enclosure, but enough for some goggles.
When testing with them i can't see any blue transmission, but i can see the spot in orange, so i'll estimate an absorption of maybe 98% of the blue light at 445nm and full transmission of the glowing, what's not so bad
This plates were samples of UV-shielding for photochemical PCB-generation, so 100%-blockers for UV and blue.
When pointing with the laser through the plate directly, it blocks the beam completelly and melts/burns away slowly, so the shielding effect is more absorption than diffuse reflection ...
Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]
Call for the project "garbage-free seas" - [reprap.org]
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Re: Laser Cutting Head December 31, 2010 10:28AM |
Hi Viktor,
You could probably use them as windows in an enclosure.
Do you have any transmission/absorption/OD data from the manufacturer to be on the safe side? According to the link, for 1W @ 445 nm CW you need an Optical Density of 3 which corresponds to a transmission of just 0.1%. More than likely you'll be ok, but when its your eyes you have to be careful!
Absorption is good - if your (goggle-covered) eye is in the beam path you'll smell/see/hear the burning and get out of the way!
What focal length lenses do you use for the tests with balsa with blue and IR? If the laser divergences are the same (probably not I guess!) then the same lens will give a smaller focal spot for the blue (spotsize depends on wavelength).
Has anybody tried sls of ceramics? I'm thinking it could be a good insulator between the hotend and extruder body... but maybe somebody has already tried and ruled that out!
I'm building a repstrap with a uv laser marker (slowly!)... hoping to use it to build a mendel and try it as a laser cutter if I can redirect my marker beam or else maybe get some diodes... its early days yet
You could probably use them as windows in an enclosure.
Do you have any transmission/absorption/OD data from the manufacturer to be on the safe side? According to the link, for 1W @ 445 nm CW you need an Optical Density of 3 which corresponds to a transmission of just 0.1%. More than likely you'll be ok, but when its your eyes you have to be careful!
Absorption is good - if your (goggle-covered) eye is in the beam path you'll smell/see/hear the burning and get out of the way!
What focal length lenses do you use for the tests with balsa with blue and IR? If the laser divergences are the same (probably not I guess!) then the same lens will give a smaller focal spot for the blue (spotsize depends on wavelength).
Has anybody tried sls of ceramics? I'm thinking it could be a good insulator between the hotend and extruder body... but maybe somebody has already tried and ruled that out!
I'm building a repstrap with a uv laser marker (slowly!)... hoping to use it to build a mendel and try it as a laser cutter if I can redirect my marker beam or else maybe get some diodes... its early days yet
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Re: Laser Cutting Head January 01, 2011 05:16PM |
... i use two small plastic lenses for the 445nm-diode which the seller added, maybe salvaged from the beam-shaping in the Casio-beamer?
I've fixed the blue diode to my CNC-mill and tested with black 0.3mm plastic:
Here with 1Watt and 500mm/min cutting speed:
... here with the UV-filterplate:
... tattoo ready:
... and cleared:
The focus is bad, maybe 0.15mm diameter compared to 0.1mm with the IR-diode.
When the collimator arrives, i'll test with other lenses - i hope to receive then a spot diameter of 0.05mm, so the energy density and cutting speed should increase dramatically
Edited 1 time(s). Last edit at 01/01/2011 05:18PM by VDX.
Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]
Call for the project "garbage-free seas" - [reprap.org]
I've fixed the blue diode to my CNC-mill and tested with black 0.3mm plastic:
Here with 1Watt and 500mm/min cutting speed:
... here with the UV-filterplate:
... tattoo ready:
... and cleared:
The focus is bad, maybe 0.15mm diameter compared to 0.1mm with the IR-diode.
When the collimator arrives, i'll test with other lenses - i hope to receive then a spot diameter of 0.05mm, so the energy density and cutting speed should increase dramatically
Edited 1 time(s). Last edit at 01/01/2011 05:18PM by VDX.
Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]
Call for the project "garbage-free seas" - [reprap.org]
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Re: Laser Cutting Head February 14, 2011 05:51PM |
I am talking/following Leonardo working on testing blue laser of 1W -- he found that his RepRap Mendel don't have the needed precision/mechanical quality for laser etch PCBs 
Now I need to go and test with my CNC, since my Reprap Mendel have just the same problems as the Leonardo RepRap Mendel.
Read here the blog message with the tests: [reonarudo.info]
---
New cutting edge RepRap electronics, ARM 32 bits @ 100MHz runs RepRap @ 725mm/s:
[www.3dprinting-r2c2.com]
Now I need to go and test with my CNC, since my Reprap Mendel have just the same problems as the Leonardo RepRap Mendel.
Read here the blog message with the tests: [reonarudo.info]
---
New cutting edge RepRap electronics, ARM 32 bits @ 100MHz runs RepRap @ 725mm/s:
[www.3dprinting-r2c2.com]
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Re: Laser Cutting Head April 07, 2011 03:01AM |
... beside developing a conversion kit for generic CNC-mills (i'm converting an Isel mill) i modified one of my 5Amps-drivers to 8.6Amps max. current by replacing three of the LM317 by LM338 and changing the sense resistors - image here under "power source": [objects.reprap.org]
When the CNC-kit works, i'll apply a 9Watts- and a 25Watts-laserdiode (both needs 9Amps for max. power) and melt some powder
Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]
Call for the project "garbage-free seas" - [reprap.org]
When the CNC-kit works, i'll apply a 9Watts- and a 25Watts-laserdiode (both needs 9Amps for max. power) and melt some powder
Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]
Call for the project "garbage-free seas" - [reprap.org]
|
Re: Laser Cutting Head December 03, 2011 08:40AM |
halo everybody,
one of the problems of the 1watt 445nm units is that in reality they are a multidiode solution (2x500mw) and that affects the the size and shape of the beam (1watt 445nm beams are not round).
there is a debate about if a single diode 500mw 405nm diode will focus better (and have better cutting results) than a 1watt 445nm unit. But on the other hand 405nm is not visible so focusing can be a bitch
Im not sure for which solution I will go for, any insights?
one of the problems of the 1watt 445nm units is that in reality they are a multidiode solution (2x500mw) and that affects the the size and shape of the beam (1watt 445nm beams are not round).
there is a debate about if a single diode 500mw 405nm diode will focus better (and have better cutting results) than a 1watt 445nm unit. But on the other hand 405nm is not visible so focusing can be a bitch
Im not sure for which solution I will go for, any insights?
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Re: Laser Cutting Head December 03, 2011 09:31AM |
waste Wrote:
-------------------------------------------------------
> halo everybody,
>
> one of the problems of the 1watt 445nm units is
> that in reality they are a multidiode solution
> (2x500mw) and that affects the the size and shape
> of the beam (1watt 445nm beams are not round).
>
> there is a debate about if a single diode 500mw
> 405nm diode will focus better (and have better
> cutting results) than a 1watt 445nm unit. But on
> the other hand 405nm is not visible so focusing
> can be a bitch
>
> Im not sure for which solution I will go for, any
> insights?
I didn't invested more on the idea of laser diode on RepRap because I am afraid to be blind. If I would know it could work in a safe way, I may invest more. I will continue monitor this message.
Waste, do you have any experiences? any blog messages that I can read about your works?
---
New cutting edge RepRap electronics, ARM 32 bits @ 100MHz runs RepRap @ 725mm/s:
[www.3dprinting-r2c2.com]
-------------------------------------------------------
> halo everybody,
>
> one of the problems of the 1watt 445nm units is
> that in reality they are a multidiode solution
> (2x500mw) and that affects the the size and shape
> of the beam (1watt 445nm beams are not round).
>
> there is a debate about if a single diode 500mw
> 405nm diode will focus better (and have better
> cutting results) than a 1watt 445nm unit. But on
> the other hand 405nm is not visible so focusing
> can be a bitch
>
> Im not sure for which solution I will go for, any
> insights?
I didn't invested more on the idea of laser diode on RepRap because I am afraid to be blind. If I would know it could work in a safe way, I may invest more. I will continue monitor this message.
Waste, do you have any experiences? any blog messages that I can read about your works?
---
New cutting edge RepRap electronics, ARM 32 bits @ 100MHz runs RepRap @ 725mm/s:
[www.3dprinting-r2c2.com]
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Re: Laser Cutting Head March 05, 2012 05:08PM |
... from another thread, but could be interesting here too - atached images of a typical 'laser-plotter' and the toolhead with integrated diode or only collimator and optics:
Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]
Call for the project "garbage-free seas" - [reprap.org]
Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]
Call for the project "garbage-free seas" - [reprap.org]
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