Making Your Mini Laser Engraver Safer and Better

Maybe you bought one?
They usually cost $80.
$150, advertised as \"DIY engraving machine for laser engraving printer cutting machine\" with names like NEJE and SuperCarver.
They are very cute and have a laser module that looks like a small laser pointer wrapped in a radiator.
However, this cute little laser is usually 300 MW, 500 MW or 1000 MW.
This is the great power to quickly burn the design into wood-
If used in an unsafe manner, it is also sufficient to cause serious damage almost immediately.
In the United States, I think many people are used to this danger.
The power laser is exaggerated.
Direct viewing of beams from IIIa laser devices such as laser indicators or laser scanners can be harmful to the eyes, but they are very safe in other ways.
The problem is that these devices can only be transmitted between 1 mW and 5 mW.
The laser in your cheap engraver may look like a laser indicator, but it provides enough power and requires a very different way of handling for safety.
Avoid the temptation to try something first and read the instructions after a serious problem arises: I didn\'t even insert
I was in my laser power supply until I built the housing for the unit.
I am not a legal expert or a laser safety expert.
I\'m just a creator who sees the potential of these little sculptors, good or bad.
You are fully responsible for the safe configuration and operation of the laser.
I wrote this instruction to make people more aware of the possibility of serious illness. . .
Describe what I have done to reduce risk and improve functionality.
All in all, when you see \"DIY\" in the advertisements of these sculptors, you may want to know what else you have left to \"do it yourself \"---
These devices seem to be fully assembled.
The answer is to install the laser and add safety features.
In fact, this Instructable not only outlines security issues and proposes fixes, but also applies improvements that make the machine more consistent and easy to use.
There are other ways to do it, but I used 3D-
Upgrade the printing of customized parts for laser engraving machine--
I have provided the design of these parts for free, so you can also.
Never forget that you can use your tools to make better ones.
Before diving into the details of how we can make the device safer, it is useful to quickly understand how much damage can be caused by the misuse of one of the laser engravers.
You can get more bloody details on what damage a laser can do from many sites, including Wikipedia articles on laser safety, laser safety fact sites, and OSHA\'s guidelines.
These small semiconductor lasers will definitely hurt you, however. . . . DON\'T PANIC!
Think of it this way: it is really dangerous to use these lasers if handled improperly, but it is also dangerous to use many power tools or drive a car incorrectly.
Everything should be good with reasonable care.
By the way, the sticker design above is the label I made to warn of danger.
I know it looks scary and your laser may not have a label like this, but it really should have.
Put the appropriate warning tag on your unit! At least print-out and fill-
In the blank sticker above
The key element of proper warning is: Needless to say, children and adults who do not know about basic laser safety issues should not use this laser without supervision.
The main materials we use when making the changes are: You also need a filament-
Squeeze 3D printers, some opaque PLA filaments, and the design STLs of these parts that we have released on Thingiverse.
There are not many things you need to print, only one piece may be too big to fit on the bed with the smallest filaments --
Squeeze the 3D printer, but it\'s hard to make these mods without 3D
Print several parts.
What tools do you need?
Well, there are a lot of options, but the easiest thing we find is: the most important security issue is to close your sculptor. . .
But this is not the first thing you should do.
Even after your laser is closed, you still need to turn it on sometimes in order to adjust the focus etc.
All this should be low.
But even low power is not without power. . .
So, wear laser safety glasses and keep shiny things away from the laser. Shiny things? Yup;
Just like the shiny aluminum construction board that comes with it.
Now, the build board looks good and there is not even a gap to help the rubber band work as a workpiece fixture, but it is definitely a danger.
Unfortunately, the way it is dressed makes it difficult to take off.
So is there a way to darken the build platform? Sure.
How about black paint or even aluminum black (
A strong acid that can bring a hard black surface to aluminum almost immediately);
Any such coating can be applied to the building platform without having to remove it from the housing.
The problem is I don\'t know what the effect of laser irradiation will have on these coatings, so I can\'t recommend them.
The best option is to remove the build platform and replace it with a laser fixture that is easy to accept interchangessafe material (i. e. , PLA)
Collect everything we want to carve.
This is easy to do if you have a 3D printer.
The second benefit is that if you need to remove the sculptor base, the improved build platform design will not get in the way of you. To swap-
Remove the aluminum construction plate, first remove the four screws on the left and right sides of the printer, which secure the black metal base plate in the appropriate position.
Unfortunately you can\'t lift the floor because the aluminum construction board gets stuck on the floor, but you can lift it up a little and push it a little, this way you can reach each of the four nuts that fix the corner of the y-axis of the CD drive.
These nuts are on four bolts at the bottom of the carving knife.
Once you remove the four nuts
Maybe turning the bolt from the bottom)
, The entire CD drive trapped floor aluminum bed can be lifted from the frame of the engraver.
There is a small screw on the bottom of the CD drive to fix the aluminum plate--
If you screw it, the aluminum plate will fall off and the bottom plate will be released.
Reassembly is very easy: use screws that fix the aluminum plate to connect 3D-
Print the base, put the disc drive back on the four bolts, tighten the nut, insert the bottom plate and replace the four side screws. Done!
The base and fixture were trimmed. to-
Stick the patch magnet on it.
To install an object for engraving, simply put it in the appropriate fixture and place the fixture on the base with the rectangle aligned to the rightside \"loop.
\"There are games on purpose, but you can get a consistent alignment by simply pushing the fixture from the right side so it can lean directly on the ring.
Unless you adjust the laser focus or move the laser module out of the alignment, the positioning is very consistent, both of which can move the image position several millimeters.
All these lovely little sculptors come with a pair of lasers
Goggles.
Wearing them can provide considerable protection. . . for the wearer.
The goggles clearly do not have any protection for innocent bystanders because they happened to have a look at the laser when cutting it.
It is also obvious that the goggles do not prevent you from reaching out and getting burned under the laser ---
Remember, it burns instantly at a higher level of energy.
The obvious difference between these small laser sculptors and larger, higher laser sculptors
The power of the industrial laser cutting machine is that the laser cutting machine is closed.
There may be a window that allows you to see what is going on through the window, but the box can reach out and the window will be made of a material designed to block most of the laser.
Windows are usually orange/red for CO2 tube lasers, and the goggles that come with our semiconductor laser engraver are green.
However, do not confuse the apparent color with the ability to effectively block the laser.
To effectively block the laser, you really need to know what the laser is.
All laser products within this power range should be output with their maximum power (
Usually mW, 1/1000ths W)
Their emission frequency (
Usually in nano, Nano).
It is disturbing that most of these mini engravers and the laser modules they come with are not marked.
They usually list only the maximum power and describe the laser color as \"blue and purple\"-
Inaccurate and inaccurate claims
In fact, the reason we purchased the HTPOW version is because, unlike most of these laser sculptors, this ad clearly states that the wavelength of the 1000 mW laser provided is 40 nm.
Let\'s say our HTPOW is correct.
The wavelength is at the visible edge of uv (UVA)
, But the light of 40 nm is visible (
Invisible laser is more dangerous)
However, it is close enough to UVA, so most glasses and plastic block it.
The green filter is easier to block this wavelength than the red or blue filter, but it depends on the specific filter.
Cinema gel filter (e. g.
, Roscolux sampler displayed)
Very cheap, the wavelength transmission curve has been released, but the drama gel is not very durable;
Unfortunately, most of the other potential filter materials do not publish a response curve.
If you see low for the time beingpower (focus)
Through the appropriate filter, the mode diffuse of the laser, the color of the light should not be purple-
It is green through the goggles.
You need a filter material that blocks the laser frequency. . .
It would be nice if it didn\'t block all the other light so you can still see through it.
Last Note on wavelength: some lasers are more than one! Why?
Because they are frequency.
Double, for example Harry nm \"green laser pointer\" that may leak laser light at 1064nm \"--
A dangerous invisible NIR (near infrared)
The wavelength at which most filter materials do not stop.
According to this point, the 445nm diode laser is not doubled in frequency, while some (but not all)
404/405 nm is actually twice that of 80 nm.
The key to ensuring eye safety is to ensure that the laser is well lit.
To do this, all you need to do is package the laser in a sculptor.
To be honest, the enclosed structure doesn\'t have to be beautiful, and a roll of tape may work well.
Heck, covering the opening in the frame with cardboard should even work.
The problem is that you want to be able to get into it easily. . .
That\'s why I made 3D.
Print window stand.
There\'s a small 3D
A printed tray suitable for each of the three sides that are completely closed.
The tray allows for a properly dark acrylic, about 126mm x 143mm (
Just shy 5 \"x a little 6 \")
, To insert the front of each side opening.
Paste a magnetic strip at the top of each piece of paper to ensure that the filter does not fall off while being accessible.
Suppose you can\'t find the appropriate transparent filter? No problem.
The dark green acrylic side panel I used was completely opaque to the laser, so I simply drilled a round hole on one of them and put a dramatic gel filter on the hole-
This protects the gel filter, but the gel filter has the desired spectral properties.
However, it is worth noting that if the carved material is on fire
Continuous fire should be seen through acrylic resin.
Don\'t you like gel filtration?
Use something completely opaque to the side panel and stick a USB webcam inside to monitor progress!
Almost all of your carving marks will eventually burn down and spread out into the air like smoke.
Except for never carving annoying materials (e. g.
PVC and other chloride plastics)
It would be nice to reduce a little smoke.
The small fan in the sculptor is not strong enough to blow the air through a heavy filter, but it is strong enough to drain the air through a layer of activated carbon filter.
It doesn\'t eliminate all the bad stuff, but it does significantly reduce the smell of the sculptor, so it obviously helps.
To be precise, the carbon filter does a good job of capturing particles, but does not capture gas. . .
So it won\'t have any effect on the toxic smoke that is produced by trying to laser insensibly
Selected materials.
In fact, even if you carve harmless material with a good air filter, you should only use it in the wellVentilation area.
Our filter assembly is very much like the other three side panels, but we will use a piece of activated carbon filter pad cut by size instead of using a piece of acrylic.
The mat is a little thicker than acrylic, so the window box-
Like it\'s sitting (ventfoot. stl)
Slotting for thicker inserts.
To keep the filter in place, there is a 3D-printed panel (vent. stl).
Just cut the filter material into the right shape, push it into the printed stand and paste the bar magnet on top of the stand.
The filter panel is installed the same as other panels.
How is this small laser controlled?
There is a micro controller at the bottom of the shell that can do the real work.
It can even be used to carve a pre-
Just press the red power button and press the center button twice to load the pattern without a computer connection.
However, you do need to connect it to your computer to change the pre-
Loaded pattern, you can control engraving more flexibly directly from the computer connected via USB.
The first thing you might want to do is replace the USB cable that comes with your device.
All of our first attempts at printing went through unpredictable times, and the sculptor would stop, skip a few lines of engraving, and continue printing as if there had never been a problem.
We initially thought it was a software problem. It wasn\'t.
Although the USB cable looks good, it runs reliably after replacement.
The USB cable that comes with our Wanhao I3 3D actually has the same problem-printer. . .
So I think we\'re seeing a trend: Some very good Chinese tools are shipping defective USB cables.
Another problem is that the sculptor really attracts too much to power through a typical computer USB port, but if it is plugged in and the AC adapter is not, it will try to do so.
This doesn\'t seem to cause any permanent damage, but it can cause unfortunate accidents like the laser turns on when the AC adapter is unplugged--
This may be an issue caused by the processor restarting in the event of a power failure.
This photo shows the controller board in our HTPOW unit.
A small study shows that this is a 8051-
Compatible with the micro controller, there are very few computing resources, but this is enough.
The problem is that it is not an ideal master for a free person
Available translations for standard G-
The code and design are strongly inclined to sculpt the image instead of drawing the lines, so it says it\'s its own protocol.
That means it\'s really tied up.
Software support that comes with it. . . .
You may think that software is not a security issue, but it is indeed a security issue.
You don\'t want the laser to remain high power due to software defects.
However, the problem is bigger than this: the software that talks to the SuperCarver controller board only runs under Windows.
Due to the lack of a USB driver, it doesn\'t even seem to work under wine on Linux.
Of course, you can always consult \"user manuel \"(
No matter who that guy is. .
OK, there are some proper English errors in the manual and the software itself. . .
This is not a big problem.
It is actually very useful if you can run the software that comes with the machine.
As a matter of fact, it is entirely image.
This is all the software you need to engrave the image.
Although this can be achieved with careful image scaling, it is not very convenient to carve/cut patterns with precise dimensions.
The Raster engraving sequence will also result in more heating marks than the printer directly following any line segment as G-
The code will specify, but the engraving quality is indeed much higher than we expected.
Obviously, 1000 MW laser has an advantage over most higher lasers
A power laser is a point where the beam can be focused to a finer point.
Assuming this is the same as the 1000 mW @ 40nm laser discussed elsewhere, the spot size is about 0. 1mm;
In contrast, the 2000 mW @ 445nm laser was quoted as having a spot size of about 0. 2mm --
If so, it means that the 1000 MW unit provides a higher energy density!
In this article, we will
Most protocols have been designed (
\"We\" I mean Paul Eberhart, who happens to be one of my graduate students).
Our goal is to write a portable G.
A code interpreter that can run on any Linux, Windows, or Apple host and send the appropriate low
Horizontal stepping and laser control commands for the cutter.
If we have a job, we will post the information here.
By the way, there are various related codes around. Arduino-Processing-Laser-
CNC is the complete code that uses the arduino to control the CD drive Walker and process code on the host to convert the image for engraving.
Other people have-
The NEJE protocol was designed. . .
This is similar to what our HTPOW SuperCarver uses, but different.
So, is this all worth working on?
How about carving?
The answer is that they are very good on the right materials and the right settings.
The example shown here is to burn too heavily in materials that are too easy to burn (
Apply the image a little)
But even it shows pretty good detail.
Motion repeatability is also good unless you adjust the laser focus or nudge the laser head, both of which can easily move the image position several millimeters.
Depending on the material and settings, it can take up to a few minutes to about an hour
Engraving size 38mm x 38mm.
In fact, the area limit of 38mm x 38mm is a serious limit, and the shape of the frame and the Y motion in the bed mean that you can\'t put the laser on a larger workpiece to make a small mark.
Nevertheless, it is a useful device in terms of its cost.
OK, I know it\'s pretty safe to watch the laser do this through a small filter window. . .
But I found myself wanting to see too much from too close.
So, here\'s how do I put a $3 webcam in there and make 100% eyes --
Watch the scene safely and allow for stills or make videos like this (
Play at the actual speed of the sculptor\'s operation).
Simple: just replace the rear panel with campanel. stl.
Like your eyes, we don\'t want the webcam to be blind, so stick a small piece of gel filter to the lens.
The webcam simply drops in place and the USB cable goes through any of the angled holes in it.
A bar magnet sticks to the top of the panel--
As we did on the acrylic panel it replaced.
The camera can rotate in the holder, so install the panel and manually adjust the angle and focus the camera;
Put a piece of tape on the camera and hold this angle for the time being.
Remove the panel from the device and use a little hot glue (or whatever)to semi-
Set the angle permanently. . .
Get rid of the tape you stuck to before. Done.
The webcam apparently has 3 white LEDs for lighting.
It actually has a clear plastic object, shaped like 3 LEDs, placed on the LED it actually has (
We don\'t want to pay for three LEDs, do we? ).
Anyway, it still provides some useful lighting for the camera and direct viewing of humans through the filter window, so turn on the light switch of the webcam.
I have no problem with both the sculptor and the webcam being controlled from the USB port on my little old atom --based netbook.
Just use any webcam software you want to provide live views and capture stills or videos.
There is a lot of free software here.
The image quality on my $3 webcam is not very good, shooting through a green gel filter does not help clarity, the brightness of the laser point really makes it automaticexposure (
Turn the brightness up and the contrast down)
But it is 640x480, very useful.