Machsupport Forum
General CNC Chat => Show"N"Tell ( What you have made with your CNC machine.) => Topic started by: Tweakie.CNC on May 03, 2009, 01:14:57 PM
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Not bad for a first attempt but I still have a lot to learn about vector laser engraving. The feed rate and dwell time at the start of each cut are all important and of course there is no Z axis movement.
Here I have used a low power (150 mW) red laser with a 650 nm wavelength fitted to the Z axis.
Tweakie.
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Wow, that's slick as hell!
You have to give up some details here, what exactly is required for setting this up?
Can a moron like me do this? :D
Thanks,
Dave
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Hi Dave,
A moron like me managed it OK.
Its a standard 150mW diode laser from China mounted to the Z axis. You can draw any vector graphics on relatively dark colored, thin, materials and woods in the same way as engraving with a cutter but at a much, much lower feed rate (too fast and it doesn't mark the surface, too slow and it cuts right through thin stuff)
Although it cuts the dark vinyls well the edges of the cuts are slightly raised where the material has melted so only 'so so' for bumper stickers and the like (drag knife cutting of vinyls is better).
What do you need to know ?.
Tweakie.
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One important thing I forgot to mention is that protective glasses or goggles are essential and must be worn at all times that the laser is powered on. 150mW doesn't seem like much power but focussed to the size of a pin point its reflected image is pretty powerful and harmful to the eyes. :'(
Tweakie.
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Tweakie that is real nice.
What about power supply can you show pictures
Is it hard to do
did you have a kit to built it or built it yourself
How much did it cost total
is it continuous use
Marcel Beaudry
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Tweakie that is real nice.
What about power supply can you show pictures
Is it hard to do
did you have a kit to built it or built it yourself
How much did it cost total
is it continuous use
Marcel Beaudry
Tweakie, basically Marcel has asked what I'd like to hear/see about. :)
How does the Z axis timing/feedrate work, isn't there a critical timing when the Z comes down to the needed height off the material?
Dave
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Looks great Tweakie. :) Pretty slick.
Brett
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now that is nice, there is a local place that does laser engraving on stainless and the like, I believe he puts some sort of compound on the top then the laser etches it and the excess is removed. Would be interesting to see exactly how its done.
Like the others are saying, would be good to hear all about your setup.
Hood
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Hey this is interesting. :)
Details of where to get this sort of laser? What to look for?
Does it need to be special to focus that well?
Greg
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This is a great project, we need to know everything, from what you have said laser eye treatment is out though >:D
Graham
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Hey Guys,
I am still learning about this process and don't know all (hardly any really) of the answers myself yet.
The laser I have used was bought last year from Virtual Village, one of the Chinese retailers, and came with its own constant current power source (picture attached) which just requires a standard 5 Volts regulated supply. It cost around £35 (GBP) plus the shipping cost.
The laser is used in CW mode (continious operation) and my GCode file was edited to delete all the +Z moves completely and replace the -Z moves with G4 P3 to give a dwell before moving off from each new starting position. When the G0 moves are made they are too fast for the laser to bite therefore focus was set once, at the start of the job and without any subsequent Z moves using a feedrate of F20 (mm/min) and G0 inbetween the results were as you can see in the initial photos. Increasing the feedrate thins the line width and reducing the feedrate thickens it. (I guess the whole process must be very similar to plasma cutting requiring pretty much the same disciplines).
I did modify the laser to add a focus ring (the clear acrylic part on the front) but all this does is allow me easy focusing adjustment without using any special tools.
This laser does focus well even though it has plastic optics (min. 30mm - max. the length of my workshop) and was originally purchased as an allignment tool for a larger YAG laser which I have been slowly constructing for the last 6 Months or so (not sure if I will ever get it finished though). It was just by chance that I fitted it to my CNC to see how it would cut vinyl. Now it is a whole new ball game and I have so much learning to do (all the laser engraving machines I have seen so far use fast raster scan and pulsed laser operation) CW operation and vector drawing is just like conventional engraving and well suited to relatively slow moving CNC machines such as mine.
Thanks Guys for the interest - I will post more info and pics as things develop.
Tweakie.
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Very interesting, Tweakie, I appreciate you taking the time to share your info on this.
Could be a fun area to dive into 8)
Dave
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Hi Dave,
I am only too pleased to share any info I have. All I know about CNC has come from you guys sharing your info.
Another piece of information - When the laser is operated at 2 Volts it produces a faint beam which is ideal for focusing because there is no loom and the beam can be adjusted to the smallest spot then it only lases when the voltage is increased to 5 Volts - pretty similar to the operation of the laser cross hair pointers we use for the tool positioning.
Couple more pics. - The Mach write wizard allows GCode to be created without Z moves which is ideal for experiments - This little laser cuts through 4mm high density foam (the stuff I use to protect RC servos and receivers) too easily, in fact it scored the surface during the fast G00 moves. It also makes short work of pvc electrical tape too.
Tweakie.
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Now that's just friggin nifty...... 8)
Dave
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Hello Tweaky
Thank you for the info
Marcel
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Great info :)
What thickness of plastic do you think it would cut?
Hood
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Thanks for the posting the info Tweakie,
Looks interesting.
RICH
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Do you have a link to where you got the laser from?
Hood
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http://www.virtualvillage.com/
They sell on Ebay too
Very serious seller, bought many times from them and never got any problem at all
Jeff
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Thought that might be the place but have searched through there and cant find a 150mw laser, must be going blind ;D
Hood
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Saw the 100 there.....but no 150.
Then saw this one on eBay... http://cgi.ebay.com/150mw-650nm-red-laser-module-with-TTL-modulation_W0QQitemZ140314566877QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item20ab6660dd&_trksid=p3286.c0.m14&_trkparms=72%3A1205%7C66%3A4%7C65%3A12%7C39%3A1%7C240%3A1318%7C301%3A0%7C293%3A1%7C294%3A200
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......and check out this store.
http://stores.shop.ebay.com/Electronic-Toys-Shop__W0QQ_armrsZ1
Some HOT ones here.
RC
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Hi Hood,
I bought the laser last year and Virtual Village stocks probably change but I am sure it will be back again. (hope so because I want another one).
This Road Runner is approx. 65mm across and laser engraved into aluminium clad plastic engraving laminate. The gloss finish stuff did not work but this matt or brushed surface is just fine. Although the line width is not quite as fine as can be achieved with an engraving point it is not far off. The laser was positioned approx. 60mm off the work and focused to the smallest spot I could get on the surface. There are a couple of dings, top right, which were the focus point and the starting and finishing point. There is also a slight line from the end of the engraving to the home position at the end of the job. I will have to connect a laser enable / disable from the LPT port and perhaps link it to the Z axis function. Does anyone have any ideas about this please ?.
Tweakie.
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Very nice Tweak.
Saw this recently...might help ?
RC
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Thanks RC,
I was thinking of using the Z axis direction signal but this looks like a better way - I must try it and see how it works.
Tweakie.
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Tweakie, nice work :)
Not to make more "work" for you, but any chance of seeing some video of it in action?
Thanks,
Dave
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Hi Dave,
At the moment I don't have a video camera (spent all my allowance on a Sony SLR and Minolta 70-210 'beercan') but just for you I will try to obtain a cheap webcam that will work with my laptop. Actually you are not missing much, with a feedrate of 20mm per minute It would probably be like watching paint dry. What would be far more interesting is a video of me photographing the laser in action as I tape one lens of the protective goggles to the camera lens filter (to give some degree of protection to my expensive image sensor) then shut one eye and look through the remaining goggle lens to take the shot. Glad no one can see me really :D
It perhaps should be noted here that viewing a laser through any optical device is a bad idea for your eyesight.
Incidentally these solid state lasers cannot be turned on quickly as they require a 'soft start' in order to meet their expected life span. Therefore, in use, switching them on and off quickly requires a shutter system and I am currently working on this to solve the problem of unwanted burns when the axis is accelerating / decelerating from the start or finish of a line. First attempt at a rotary shutter was not too successful so I either have to improve on it or start again with a sliding shutter idea. I will add to this post when I have more information.
Tweakie.
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If you want to learn more about lasers go to http://photonlexicon.com/forums/index.php
There are a lot of good people there that would be glad to help you. Also if you can get a cheap TTL driver for your laser and be able to modulate it at high speeds. If you go with an analog driver you will be able to control the power output not just off and on.
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Thanx for the link - much appreciated.
Tweakie.
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one day when im big i will give this a try :)
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Why wait until you are big ?.
Tweakie
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cuz i have to ask my missus for pocket money for side projects....
an my missus is MEAN......
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cuz i have to ask my missus for pocket money for side projects....
an my missus is MEAN......
That explains the milling in the middle of the night ;)
Dave
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:D
Tweakie
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hehehehe
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Now this is what I call cutting - I do have a fire extinguisher standing by.
Tweakie.
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It's like the sun ;D
Dave
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oh damn.. nowe i cant decide ifi want to do the laser thing or cnc'ng my lathe first..
im thinking laser is cheaper....
im gonna mail you Tweakie for info... soon as I remember! im a visual learner.. all these words .. scribble scribble scribble.. a picture is worth a million words...
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Tweakie,
Wonder what you did with a magnifying glass on a sunny day when you were a kid! ;D
We tend to build on past experiences! ;) :) :)
RICH
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Another photo I thought you may be interested in seeing.
Tweakie.
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That's just cool Tweakie............... Very neat. Can you cut acetal with it I wonder? I think that is right......... it is a clear thin film used often to make stencils for airbrushing.
Brett
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I believe you mean acetate, Brett? Acetal is a type of plastic.
Awesome, Tweaks!
Dave
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Hi Brett,
Transparent or clear materials are just not touched at all as these low power lasers favor the darker materials the best.
Now coloured acetate would probably work OK if it was thin enough, certainly the dark coloured Vinyls (sticky backed plastic) cut very well.
Tweakie.
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Dave reminding me about the magnifying glass as a kid led me to think about an offset parabolic satellite dish on a polar mount with the dish actuator driven by a simple 2 photo diode sun tracking system – assuming the dish was steel it could be chrome plated and polished with a water cooled collimating lens fitted in place of the LNB. This collimating lens would feed into a gas cooled fiber optic cable that was led to the CNC Z axis and in turn a water cooled focusing lens. OK it is straight out of the James Bond film but it is not rocket science and may not be practical here in the UK because of the frequent cloud cover but for some of you guys in North America it could be a practical proposition. It would not produce megawatts of power but I bet it would be more than the 150 mW I am currently using.
What do you think, would it work ?.
Tweakie.
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Thanks Dave and Tweakie,
LOL Tweakie, I'm in mostly sunny and hot South Carolina so it would defiantly work here.................. if it didn't melt the fiber optics. ;D Tweakie Death Ray!!!!!!!!! ;D
Brett
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It sure sounds feasable, Tweaks, and you're just the man to prove it :D
Dave
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this might interest ppl who want to use fiber optics i found these on eBay the first one might be gone by the time you read this.
2.5w laser
http://cgi.ebay.com/Laser-Diode-2-5W-920nm-Fiber-Coupled-Burns-SDL-6380-L2_W0QQitemZ250421201182QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3a4e44491e&_trksid=p4634.c0.m14.l1262&_trkparms=%7C301%3A1%7C293%3A1%7C294%3A30
1w laser
http://cgi.ebay.com/1-Watt-Fiber-Coupled-Laser-Diode-830nm-Infrared-Burning_W0QQitemZ250421201253QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3a4e444965&_trksid=p4634.c0.m14.l1262&_trkparms=%7C301%3A0%7C293%3A1%7C294%3A30
and an adapter
http://cgi.ebay.com/Bare-Fiber-Adapter-ST-Optic-Coupled-Laser-Diode_W0QQitemZ250421201227QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3a4e44494b&_trksid=p4634.c0.m14.l1262&_trkparms=%7C301%3A0%7C293%3A1%7C294%3A30
this is for information only i have no exsperiance with lasers but i am interested in looking into it more. i light of that i have just bought a 300mw laser from ebay to experiment with.
this thread has proved to be an eye opener as it seems i may be able to do laser engraving at a very reasonable price
thanks to everyone in it
martin
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wow!! tweakie your brain must hurt at night dude!!!
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ok tweakie.. im ready to try this i think.... (im at a loose end)
having played at it for a while will you recommend anything different from what you have now? something your eye may have fallen on that you would have done differently perhaps?
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Chris - In the process of experimentation I have concluded that a shutter system (to turn the laser on and off) is preferable to using the modulation input (at TTL levels). This enables the laser diode to be operated by a completely isolated constant current source and eliminates any possibility of voltage spikes from the machine or computer causing any damage to the diode. I have detailed what I have done so far on my website and the link is below. I will include the shutter details when I have time. Good luck and I look forward to seeing your results.
http://www.cooperman.talktalk.net/index_files/Page4549.htm
Tweakie.
btw. thanx for the links Martin.
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ok read it... i think the ability to build and wire a shutter system at this point in the game is out of my league .. i have never cut anything besides wax and im not sure my spindle will handle continuous aluminium cutting either....
Im going to be frank with you here.. i see a completely different application for this and im chasing it for that...
lets say that this laser was way to powerfull for my intended needs.. lets say i was thinking about focusing to a 0.127mm (+-) spot at only maybe 70' celcius and running a finishign pass over my wax to just just surface melt the toolmarks away... fairly fast feed cuz we dont want to punch a hole thru the wax either, literally just melt the 0.127 spot at its very very least amount of time.. some large amount of experimentation with feeds will be needed and with laser temps etc.
think thats possible?
if so.. this will have a huge commercial application... tool marks are the bane of jewellers existence...
your thoughts?
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im on this train of thought5 because a friend has a hot air blower to do similar but it is very hard to control accurately
images of hot air method
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ok first bit of farting around with laser.. nicked this off my bandsaw.. mounted to my spindle.. battery powered with a switch.. as a jeweler Y is a constant so X is the only thing i need to drive to before a cut..
Tweakie.. thanks for your inspirations dude.
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OK Chris, I see the application - brilliant idea. If you use modulation to control the laser (0 to 15kHz say) you will be able to have full command over the amount of radiated power from the laser for any feed rate that you choose. I have not seen modulation units for sale but it would be relatively easy to construct, I think, using a 555 timer or the like to create a variable PRF of a fixed width pulse. I will give this more thought and report back.
Tweakie.
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you ROCK dude!
here is a typical path that i would like to use "melt polishing" on.. this is the actual cutting path at a 0.025mm stepover, for the melt polishing i guess stepover could be lower.. maybe by factor of 2?
this is that pendant jobby by the way, would require a 4th axis to do a flip or manually edit the code to do a flip at the A180 instruction.
not sure if this helps but this like i said is a typical path for most jewellers.
the kicker here will be where the path comes to the claws tat are 2mm or so higher than the rest, meaning the laser will be dwelling in the same place for longer in those areas while Z climbs the hill.. but no science is perfect.. there will always be some scenarios this idea will not be suitable to.
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oops cut parameters
0.127mm flat profile edge cutter. 600mm/min, 0.025 stepover..
melt would be maybe 0.254mm at 0.075mm stepover? to make sure we overlay edges
not sure on this... thats the hassle with making stuff up.. nothing else to reference :)
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As far as I can see the Z dwell is no problem as this can avoided by the Z inhibit function within Mach. The major problem here is that your existing toolpath makes multiple X passes between each Y move and you would probably end up producing laser marks to replace the tool marks. :'(
Tweakie.
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Great ideas fella's!
Chris, not sure how a diode laser would work, but I can tell you my yag laser is totally worthless for polishing wax. The beam tends to bounce off or blow right through in unexpected areas; even at very low settings. ;D
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hey Ken :), hence the thinking on a pulsing point at much lower temps.. about 90C im guessing
@ Tweakie.. ok so then make the stepover the exact diameter of the point?
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may have to melt up some of me specail anaemic wax to test on.. its pretty damn solid in color.. not as translucent as the purple or blue stuff.....
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Well Chris the results were not successful. I cut your pendant, before my wife had even noticed that the candles were missing from the lounge, it is nowhere near to your high quality of work but OK for my testing. I have concluded that with a point laser beam the heat generated is too localised to cause the type of surface reflow of the wax that is required. This does not mean that it is not possible but I think that the beam would have to be modified to more of a fan shape and of course that would require considerable power from a laser and well beyond my 150 mW.
My point beam is smaller than 0.1mm so in the test I used a step over of 0.1mm and the surface finish of the wax was not improved at all – in fact it was a lot worse. The microscope photos show the surface finish after machining and after laser treatment. It was a long shot but who knows it might have worked !. :'(
Tweakie.
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dude! nice cutting hehehe hope yr wife didnt mind too much lol
ok that answers that question.. i think ou are right .. a broader point , maybe pulsing...
many guys that polish wax do it with the tip of a waxpen.. basically a heated wire.. my next experiment would likely involve some sort of heated cutter.
thansk for all your effort on this man!
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oh hey what are you magnifying that with??
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Chris what you are looking for is a larger point, little more power and the laser pulse function art developed a while back for laser/enpact engraving. That will allow you to control the power at the wax so you can "tune" the melt/flow process.
Also I believe machine wax and candle wax have a different melt point???
Just a thought, (;-) TP
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Also I believe machine wax and candle wax have a different melt point???
Exactly what I was thinking. The color would also likely play a huge part of the equation. Black would of course heat up the most, which might or might not be best. I'm sure there is something you could add to the wax to make the melting temp higher, if need be. It kinda looks like a process that uses a very defined set of parameters to work correctly. Once ya get it figured out, though, it seems it would be very rewarding.
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What about a hot air plastic welding gun?
A small nozzle and the precise travel rate, distance from target and stepover provided by the CNC to get consistency.
Greg
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good idea.. only hassle i still perceive here wil be dwell issues when Z has to climb up a claw.. the heat will be the same for a longer period of time....
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greg.. any links to the type of plastic welder you referring to?
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I always start with google.
http://images.google.com.au/images?hl=en&ei=gxIaSsrHJ5fisgPghNGSDw&resnum=1&q=plastic%20welding%20gun&um=1&ie=UTF-8&sa=N&tab=wi
ebay has a good selection too.
Greg
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looking now .. they all seem rather course tho.. thought you might have had a specific model in mind.
suppose could not be too hard to pipe air through copper tube with regular jewellers torch nozzle on end to reduce it to pinpoint..
thanks for the help :)
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or we could attach a boiler to the bottom of the copper tubing.. fil it with fruits and barley.. fermentation agents...
hmmmmm
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Hi Tweakie
FYI
One way that higher powered lasers are modulated (turned on and off) is with a device called acousto-optic modulator. What they do is bend the beam just enough that they dont get thru an aperature after the crystal.
Last one I bought for work cost close to $1k but maybe you can find something on ebay. Galvos are also used but are not (I believe) as fast as AOM's
Cheers
Mark
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Hi Mark,
Thanks for your input on this thread.
I have a 'Q Switch' on my YAG laser which does as you say bend the beam but It is too large for this project also it is designed specifically for 1064 nm and not a 655 nm red laser. I will check ebay more often to see if anything comes up.
After much experimentation I have now decided to use a shutter system for beam on/off which is driven by a small 4 position stepper motor (couldn't find a galvo without having to buy a disco light and stripping it for the parts) linked to the Z axis direction signal. It is quite fast in operation, performs like a galvo and seems OK. I am using PRF modulation of a 20nS pulse for control of the diode power output but am still experimenting with different pulse widths and modulation circuits.
To me, probably the most surprising thing about this project is that low power lasers do have useful applications with CNC machines.
Best regards,
Tweakie.
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WOW WOW WOW how cool, well maybe that's the wrong word ::).
Thanks for sharing, guess I need to make another CNC... don't think MDF and lasers mix :)
Great job on the website, wish the pictures expanded though with such cool project I would like to see the details in each.
Thanks for keeping me motivated Kent
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Thanks for the kind words Kent.
One thing about using lasers is that there is no loading on the tool head therefore even converted pen plotters would be good to use. You need to have no worries about MDF with low power lasers - the worst that could happen is a few scorch marks perhaps. ;D
Tweakie.
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ok.. ordered 1 x 200mw laser and 5 small focusable line lasers to better "aid" in my experiments...
wife gave go ahead..
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You guys all using red hene wavelength lasers? I wonder how a green ones go.. got a couple lying around.
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200mw laser cannot be delivered by the company i ordered it from because these lasers may not be supplied anymore due to some FDA laws just passed... they can supply the line lasers tho.
managed to find a 150mw one somewhere else. will do as well? ordered anyway?
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Yea - Australia prohibits imports of anything greater than 50 mW.
Never tried green lasers either - please post your results.
Tweakie.
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Guys, different types of laser produce different wavelengths, and you need to select the right wavelength for the material in question, eg a wavelength that is absorbed.
Invisible IR from a CO2 laser is ideal for cutting / marking acrylic, marking glass, cutting / marking wood, leather, etc etc...
Here in the UK you can buy *********e chinese aircooled CO2 lasers for around 250 quid for 25 watts, just add a neon sign transformer and some fans and you're good to go, for a couple of thousand hours.
Pukka sealed for life and lasts for 5k 10k CO2 hours laser cost more, as do water cooled.
Coherent and Synrad both make visible spectrum diode lasers in the multi watt range, (as well as CO2) not so good at cutting transparent materials or metals... quite expensive because you end up needing a quality PSU that can deliver 100 amperes at 2.0 volts, exactly for even a moderately powered beam...
CO2 is a lot more versatile, you can cut metal with it, just a question of power.
As a rule of thumb, you get about 2 watts of power per inch of tube, think on this if planning on mounting the tube in the Z axis, if not, if planning on using flying optics, good luck to you on the precision front.... think about it.
A 25 watt CO2 laser will slowly cut clean through 10 mm acrylic, a 100 watt will cut eighth inch steel plate.
CO2 laser basically operate at RF, so you can switch them on and off very, very, very fast, which can be useful.
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Now, everyone talks about eye safety, and this is true, even a 1 watt laser focused by the eye lens on the retina will permanently blind you before your brain even begins the blink reaction, and thats a visible laser, IR is even worse, except IR flashback can be very easy prevented by using an IR opaque medium, like acrylic or pilkington glass, this is how greenhouses work after all
HOWEVER
Permanent blindness is not the issue.
I emailed tweakie about this, a laser essentially creates a high energy plasma cloud of chemical elements from the substance being lasered, and all sorts of rubbers and plastics and other materials start giving off clouds of extremely toxic and / or carcinogenic compounds like benzine, phosgene, arsenic, chlorine etc etc etc...
Laser cut steel creates clouds of micron sized rust
Laser cut stainless steel creates clouds of very nasty heavy metals like chromium etc that once absorbed the body can never rid itself of...
As I said to tweakie it would probably be healthier to hand my small son a lit cigar than to let him be in the same room as a cutting or engraving laser, even if he was wearing a welding mask...
CO2 lasers are a lot like gas axes, they have a jet of gas (often just dry clean air) shooting out the same nozzle as the beam, and the gas jet is what really does the cutting, the laser just melts.
Essentially the difference between a 25 watt CO2 laser and a 100 watt CO2 laser is that any job the 25 watt one can do, the 100 watt can do at 4 times the feed. However, but there is a lower limit for each material and job, and that limit is the ability to punch through fast enough to have minimal deflection and to move fast enough to have minimal heat going anywhere except the desired spot.
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DO NOT BUY 150 mW laser diodes for big bucks, every single old CD burner has one in it with a lens, for free... DVD burners nearer 200 mW.
a suitable hole bored longwise in a CPU heatsink and fan is good for cooling, and long life on diodes is good cooling, good power (within limits), soft start and stop
Forget visible light diode lasers unless you want to run a light show, invisible IR is where it is at for delivered energy, but requires slightly special optics, not just ordinary glass lenses.
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If you're serious about it a 25 watt CO2 tube, neon sign transformer and tube cooling is dead simple, and actually works out a lot cheaper per watt than a 150/250 mW diode bought new, plus PSU, etc, and optics are affordable, and a clean air supply for the jet, just watch out for the 22kvolts and the instant blindness or instant 3rd degree burns, but you be able to cut most organics and plastics up to 10mm thick slowly, and engrave most plastics, glass, and organics and even metal (after pre treating) quite fast indeed.
HTH etc
cheers
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I underline the points about the toxic fumes.
Good posting John.
btw. Have you tried cutting acrylic with a laser - what sort of surface finish do you get at the edges ?.
Tweakie.
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A CO2 laser at the right power / feed produces an optically clear polished finish.
All forms of mechanical cutting require flame polishing to replicate this.
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my lasers arrived while i was away.. my supposed 150mw turned out to be a 100mw and it cant melt butter much less cut plastic. i think i have been had.
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Just a word of consolation - my laser won't melt butter either.
However if somebody ever produced black butter the laser would surely cut it !.
Tweakie.
btw. These low power lasers have to be focussed to a dot the size of a pin point to have any affect on anything - do you have a good lens ?.
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i have a focusing lense in it and when i get it to pinpoint againts a surface its so bright it hurts my eyes.
i may be powering it incorrectly tho. the website say 5V ac so im usinga 5v AC @ 1000mah usb charger. possibly not enough power?
there is a secondary cable which no one, even the suplier is able to tell me anything about.
here are pics..
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red and black are powerd by 5v AC by the way. blue and white i have no idea about?
[edit]
ok i got it burning. tried on black and blue surfaces and it started burning instantly..
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Chris,
You need to be wearing protective goggles. Do not look at the reflected beam without them.
If you use a benchtop PSU then providing 2 to 3 volts to the laser control board the laser will emit a LED beam (without lasing) which is easy to focus. Then turn up the wick to 5 Volts. (a DC power source would be better).
Tweakie.
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Class 1
A class 1 laser is safe under all conditions of normal use. This means the maximum permissible exposure (MPE) cannot be exceeded. This class includes high-power lasers within an enclosure that prevents exposure to the radiation and that cannot be opened without shutting down the laser. For example, a continuous laser at 600 nm can emit up to 0.39 mW, but for shorter wavelengths, the maximum emission is lower because of the potential of those wavelengths to generate photochemical damage. The maximum emission is also related to the pulse duration in the case of pulsed lasers and the degree of spatial coherence.
Class 1M
A Class 1M laser is safe for all conditions of use except when passed through magnifying optics such as microscopes and telescopes. Class 1M lasers produce large-diameter beams, or beams that are divergent. The MPE for a Class 1M laser cannot normally be exceeded unless focusing or imaging optics are used to narrow the beam. If the beam is refocused, the hazard of Class 1M lasers may be increased and the product class may be changed. A laser can be classified as Class 1M if the total output power is below class 3B but the power that can pass through the pupil of the eye is within Class 1.
Class 2
A Class 2 laser is safe because the blink reflex will limit the exposure to no more than 0.25 seconds. It only applies to visible-light lasers (400–700 nm). Class-2 lasers are limited to 1 mW continuous wave, or more if the emission time is less than 0.25 seconds or if the light is not spatially coherent. Intentional suppression of the blink reflex could lead to eye injury. Many laser pointers are class 2.
Class 2M
A Class 2M laser is safe because of the blink reflex if not viewed through optical instruments. As with class 1M, this applies to laser beams with a large diameter or large divergence, for which the amount of light passing through the pupil cannot exceed the limits for class 2.
Class 3R
A Class 3R laser is considered safe if handled carefully, with restricted beam viewing. With a class 3R laser, the MPE can be exceeded, but with a low risk of injury. Visible continuous lasers in Class 3R are limited to 5 mW. For other wavelengths and for pulsed lasers, other limits apply.
Class 3B
A Class 3B laser is hazardous if the eye is exposed directly, but diffuse reflections such as from paper or other matte surfaces are not harmful. Continuous lasers in the wavelength range from 315 nm to far infrared are limited to 0.5 W. For pulsed lasers between 400 and 700 nm, the limit is 30 mJ. Other limits apply to other wavelengths and to ultrashort pulsed lasers. Protective eyewear is typically required where direct viewing of a class 3B laser beam may occur. Class-3B lasers must be equipped with a key switch and a safety interlock.
Class 4
Class 4 lasers include all lasers with beam power greater than class 3B. By definition, a class-4 laser can burn the skin, in addition to potentially devastating and permanent eye damage as a result of direct or diffuse beam viewing. These lasers may ignite combustible materials, and thus may represent a fire risk. Class 4 lasers must be equipped with a key switch and a safety interlock. Many industrial, scientific, military, and medical lasers are in this category.
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Basically the above means that even the reflected and diffused beam from a 100mW laser is sufficient to cause irreparable, permanent, eye damage in less than 0.2 seconds.
Do not forget that at visible wavelengths, where the eye lens can focus the beam, a coherent beam entering the eye is focused to a point 100,000 times more powerful at the retina.
I know a man who has a permanent black spot covering about 25% of his field of vision in one eye, he described hearing a sort of "pop" inside his head as the beam caused boiling and cavitation inside his eye.
It was a 250mW "green" laser that did it.
Amongst other things he lost his truck drivers licence over it, one eyed jacks need not apply for a truck licence in the UK.
=====================
I have another mate who *KNOWS* lasers, he has a home built 80 watt CO2 laser, home built as he built everything, even the tube.
he dons a high end pair of very specific to the wavelength goggles, and then a modified welding mask with a thick slab of pilkington glass, before going anywhere near the power switch.
I laughed at him the first time I saw this, and he told me a story about some lab tech in the states in the mid eighties who had an "accident", the first thing the beam encountered was matey's protective goggles.
it burnt a hole in them.........
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ok i get it. be carefull!
i will be carefull. i think this 100mw laser is no good tho. i found a 750mw blue one on ebay for 39 bucks with driver kit.
welding goggles it is then!
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Hi Chris,
You really need to get goggles that have an optical density rated for the wavelength of the laser you are using. Welding goggles may protect your eyes but they are too dark to be of any real practical use.
Tweakie.
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ok so where to look?
this one is 655nm
these claim to do the entire red spectrum
http://store.oemlasersystems.com/index.php?main_page=product_info&cPath=8_10_14&products_id=33&zenid=c530ad286dc32f19b5b392457c394068
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Hi Chris,
If, like me, you need to wear spectacles for close up work then the goggle variety of protective eye ware are preferable as you can still wear your spectacles and wear the goggles at the same time.
Tweakie.
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Apropos of nothing, the latest price list landed in my inbox this am, Chinese stuff in US$...
25 watt CO2 laser tube $127 or 40W for $158
pukka DC PSU for above $172
ZnSe or GaAs lenses various lengths etc $30 to $45
Cu mirror $16 quartz / silicon / molybdenum too
So you're looking at 400 bucks for something that will actually cut and etch etc, vastly versatile with PWM or potentiometer control on the laser, and if you bolt it to the Z axis that takes care of movement too.
Now I'm going to ask you, how much are you spending on "experiments"?
I know I wasted 12 months and maybe 20% of the cost of my CNC conversion by being cautious instead of being bold, determining what was needed, and going out and doing it.
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Looks good prices John - are you going to buy a kit of parts then ?.
For me, CNC stuff is not so much about 'spending money on experiments' it's all about acquiring practical knowledge and practical experience. The theory can easily be obtained for free.
Tweakie.
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Hi Chris,
The secondary cable on your laser controller board is for the TTL modulation input, if you choose to use it. The white wire is connected to ground and the blue wire is for the TTL signal (<0.5 Volt=closed and >2 Volt=open) this already incorporates a 'pull up' resistor so pulling the blue wire to ground turns the laser off and open circuit turns the laser on. The spec for the modulation input is TTL levels at a frequency no greater than 15 kHz.
Tweakie.
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thanks :)
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Thanks for sharing all the information!
I’m ready to try this.
My objectives:
1. Add a bracket to my Romaxx CNC so that I could use either my Bosch Colt router or the laser without any change out using Mach3.
2. Use the “Laser” to engrave wood only and if possible cut wood of a thickness of .0625 minimum and if possible up to .25.
3. Always wear the proper type of “Laser” safety glasses.
Here is the unit I’m looking at:
http://cgi.ebay.com/High-Power-Laser-Module-1000-mw-Cutting-Burning_W0QQitemZ180347420212QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item29fd8b3e34&_trksid=p4634.c0.m14.l1262&_trkparms=%7C293%3A1%7C294%3A30
A. Will this meet my objective?
B. I understand that I will need a power supply. Are there any other components that will be needed?
C. Do you have other recommendations that you think would be better than this unit?
D. Will this type of “Laser” have any issues with engraving on different types and colors of wood?
E. If you cut wood, will you need to build or purchase a bed to lay the material on?
Thanks Again,
Bill
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Here is the unit I’m looking at:
http://cgi.ebay.com/High-Power-Laser-Module-1000-mw-Cutting-Burning_W0QQitemZ180347420212QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item29fd8b3e34&_trksid=p4634.c0.m14.l1262&_trkparms=%7C293%3A1%7C294%3A30
are you insane?
445 bucks for 1 watt and no PSU
you could just about put together a 25 watt co2 system for that money, and actually have full power control over the laser output via cnc / pwm
if you want to cut you need a lens / gas jet assembly, end of story, without it you're just melting your way through. and yes you need a cutting bed, always...
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Hi Bill,
I will try to answer your questions as best I can. Please note that this is not definitive but just my opinions based on my experiences so far.
A. I have no working knowledge of these Turkish lasers as no one has yet reported back on their use. Provided the supplied lens will actually focus the beam to a spot the size of a pin point (within the available space on your machine) then the 1 Watt of laser power looks good.
B. Additionaly you will, I think, need to cool the diode casing with a larger heatsink and perhaps CPU type fan.
C. I have no recommendations.
D. Using a laser which is only 1/7 the power of this one - I have not had too much trouble with engraving different types of wood however the surface reflectivity of the wood is the controlling factor and a finely sanded surface seems to be better. Surface burn marks adjacent to the cuts are a problem to control however.
E. I suggest just laying the work onto a sacrificial board such as plywood would be OK.
Good luck with your project Bill - Please report back to the forum with your results.
Tweakie
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Thanks Tweakie and Guy,
I appreciate you both for your wiliness to give an honest opinion. Guy, that was a funny comment about being insane. HA The answer is yes! (in a good way, me thinks) The only thing I know about a “Laser” is that I’m impressed with the engraving applications and I could use one for my wood projects. I’m with you regarding getting the most for your money but unless someone offers up a different option that is kind of easy like this one; I will go ahead and give it a try. I will definitely wait to see if you or anyone else has a recommendation to consider. I know that this is an experimental type of deal. If I’m wrong about this being kind of an easy setup, please speak up. Guy, you mentioned having control via the CNC machine and this unit does come with a driver circuit board that works with Mach3 so I was think’n that this would work. What system do you use? It sounds like you use a more powerful system.
Tweakie, I had no idea that a heat sink and fan would probably be needed. I will figure that out before I do anything. I was excited to finally see someone actually having success doing this. The add on “Laser” seems to be perfect for my engraving needs and maybe I will be able to cut with it as advertized but I won’t get my hopes up on that.
The point about burning on the edges is something that I had heard of. A printing company has a nice 30K! system and he explained that he uses wood that has a coating on it and this eliminates the issue. In general, I would not use this type of pretreated wood but I would like to find out if there is a coating that could be used. The burned edges in some engraving applications could give a branding iron type effect maybe.
Any other comments will certainly be appreciated.
Thanks Again!
Bill
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1/ I do not use a laser system at home, yet. I have used many laser systems.
2/ diode lasers "seem" like a cool idea, until you realise the drawbacks...
3/ diode laser like soft start and soft stop or they die very fast, CO2 lasers can go on/off at 10kHz or more no problemo
4/ diode lasers need low voltage and high current, CO2 lasers need high voltage and low current, lot cheaper...
5/ diode lasers above milliwatts aren't spot / single small round beam type diodes any more, they are usually bar / wide flat beam type diodes, suddenly the whole optics thing gets far more complex.
6/ diode lasers generally don't produce pukka IR which is what you really need to cut and engrave, diode lasers are FANTASTIC for use in creating light shows.
================
I've seen with my own eyes 18 watt CO2 lasers vastly outperform 50 watt diode fibre lasers on wood / plastics / leather marking and cutting, not just in quality, not just in speed, but also in ease of use... but then the fibre laser was bought to engrave part numbers and branding on to small precision metal parts, and that job it did EXTREMELY well.
Tweakie has in reality gone about as far as you can with the low power laser diodes, rip apart an old CD or DVD burner if you want to play on the cheap, but it will tell you nothing useful about high power laser diodes or high power CO2 lasers.
CO2 lasers are basically just a glass tube with an anode at one end and a cathode at the other, and a mixture of gases inside which are excited by the high voltage (15-25 kV) much like a neon tube or flourescent tube... they really are as non complex as that.
the big difference between a neon tube and a laser tube is the mirrors and lenses, interestingly made of semiconductors for IR wavelengths, plus the tube is die straight, plus it may have an outer sheath that is water cooled.
the CO2 laser PSU is not just a neon transformer HT source, you can connect a potentiometer up to it, or a CNC machine output, and get on/off and PWM control of power, so your XY machine moves at a constant mm/sec and the laser simply goes on/off and various power levels to get the desired effect...
unlike the diode laser the tube CO2 laser can do this on/off PWM thing at many kilohertz with no ill effects.
to CUT as opposed to ENGRAVE you need (should have with engrave too really) a combined focus lens and air jet, so the vapourised material is blown away, you need to match feed rates / laser power / PWM duty cycle well to cut or engrave cleanly, with a CO2 laser PSU capable of multi-kilohertz response this is a piece of piss, 50mm/min @ 50% PWM gives the same delivered power per mm2 of work as 100mm/min @ 100% PWM, but on a given wood each may well burn to a different colour, hello "grayscale" - don't even dream about doing this with a diode / fibre laser.
Fixed laser tube and flying optics adds hugely to the build cost, those optics have to be spot on at both ends of the table X and Y travel, then more complication for Z focus... if you can mount the tube on the Z things get vastly simpler and cheaper.
health and safety and other legal stuff also adds vastly to the cost, HEPA air filters and sealed negative pressure cabinets and so on and so forth all start costing lots of money very quickly indeed... in my shed I don't need any of that stuff, I have a brain, and I'm not selling it as a turnkey commercial product.
-----------------------------
in science fiction the defence against a laser is a mirror, and basically it is right, anything that is "shiny" to THE FREQUENCY AT WHICH THE LASER DELIVERS THE BULK OF ITS POWER will not cut or mark at all well, an IR CO2 laser works best all round because not many things are "shiny" to IR, far more stuff is "shiny" to visible light..
Tweakies lower power diode laser will simply bounce off a glass mirror, but turn it the other way round and it will slowly burn through the silver coating on the rear of the mirror, then paint it black and you have a nice fancy mirror.
As anyone with a greenhouse or who drives knows, UV goes through glass and IR doesn't, so it is a LOT easier to engrave glass with an IR CO2 laser than with a visible light laser, the visible light laser will usually melt and crack the glass before it engraves, the CO2 will engrave on a mere fraction of the power the diode laser uses, and the flipside of power is feed speed, if a is 100 times as effective as b then a uses 100 times the feed speed.
A 50 watt diode / fibre laser is absolutely great if all you ever want to do is mark / etch metal all day long, it is basically ********* all use for cutting out material into patterns, cutting gaskets, engraving glass, or anything else.
---------------------------------
In closing
cheap CO2 laser tubes have a bad rep for "short life", eg 1,500 hours or so, you get a LOT more hours running it from a pukka DC laser power source than you do from a neon sign transformer, which costs nearly as much anyway, plus, 1,500 hours is 30 hours a week for a year, if you use it 5 hours a week it is six years, and don't forget diode laser life is not that much longer, and literally and absolutely killed the instant you use anything other than an ideal power source, it's like being given a random light bulb, the difference between "bright" and "blown" is fractional, but a tungsten filament light bulb is about a thousand times more forgiving than a laser diode... you could get (all other things being equal) 750/800 mW out of a bog standard DVD writer diode for several hours, maybe tens of hours, and save 455 bucks over that ebay thing, which is TOTALLY lacking in all the essential info (looks like a surplus Coherent unit though)
but tubes are fairly cheap and easy to swap out, just like changing a flourescent tube in many respects.
CO2 lasers are also very well understood, which means it is easy and cheap to take adequate safety precautions, unlike diode / fibre lasers you can actually watch a CO2 laser below about 50 watts work via a sheet of thick glass / acrylic and safety goggles
CO2 lasers are mass produced, and the only game in town when it comes to producing a genuine beam at any decent levels of power, with no extra peripherals required.
CO2 lasers have essentially infinitely adjustable power output, diode lasers do not, more like an arc lamp, and CO2 lasers can be turned on and off in 1 thousandth of a second, diode lasers can not, you're talking multiples of tenths of a second to ramp up and down.
HTH etc
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Hi everybody,
More for information only, as I have already posted the picture on another thread, but these little gaskets were cut with a 150 mW diode laser.
The crankcase was scanned (on my printer/scanner) and the image converted to vector and then to GCode. The gaskets produced are a perfect fit and probably a good example of what can be achieved.
Tweakie.
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That is impressive! Especially considering that you don’t have much money in your system and that a cheap China Laser is $1500US plus.
How long does it take to cut something like the gasket?
Thanks,
Bill
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Hi Bill,
As far as I can remember the feedrate was set at 30 mm/minute so total time would have been around 15 minutes per gasket. OK it is very slow but then I have all the time that God has decided to allow me.
Tweakie.
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Thanks Tweakie,
Slow, yes but you have found another way to use your CNC. I'm starting to understand. I can see that this little add on is not really going to satisfy someone who needs a laser for anything more than making a few slow but precise parts or engravings. I can also see that the durability issue needs to be considered before purchasing a $455 experiment like I'm considering. It would be nice to own an Epilog Zing 60W but I bet the price is over $8000US. Just guessing. I'm not sure I really want to know. HA! I did some other researching/dreaming to see what the small Laser Engravers cost and I found some $1500 China EBay "deals". I'm not too sure about those.
I wonder if the 1W unit would be much faster? I do my 2D CAD work using BobCadCam and I generate my GCode from there. I can import .BMP images which I have played around with. I read that you do some editing to remove Z movement from the GCode and I guess that is something else I need to consider. The engraving I would like to do is on the same size and quality as your Daisy Azimuth but much more detailed and I would like to cut a few small parts that are .0625 in thickness but my router will do that. I also wonder about programing the start and stop that I assume is required. I think I have too many questions to ask at this point but all of this information has been extremely helpful.
I'm still think'n and learn'n.
Bill
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Hi Bill,
Initially I did edit out the Z moves but have now found that there is advantage to leaving the code 'as is'. I now disable the Z axis movement and make use of the Z code, by altering the Z Axis DRO scale factor to set the required dwell time.
Guy is, of course, quite right - If you want to do serious work then you need a serious laser and as we already know, nothing in the world of CNC comes cheap.
Tweakie.
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here are my first results tweakie. been pretty sick and had family issues so bit delayed. th "tick" marks are from bad pathing. brought Z down in a ramping move by mistake. will retest later.
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Brilliant.
Tweakie.
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thanks. building my own bluray laser now. hoping to get sustained 400mw from it. been on the laser forums a bit :)
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Look forward to seeing the results Chris.
Tweakie.
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!!!
http://cgi.ebay.com/980nm-500mw-large-Power-Red-Laser-Module_W0QQitemZ260436822168QQcmdZViewItemQQptZUK_BOI_Industrial_Tools_Generators_ET?hash=item3ca33e8898&_trksid=p4634.c0.m14.l1262&_trkparms=|293%3A1|294%3A30
good buy?
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Hi Chris,
The output from this is in the infrared part of the spectrum so the beam is hardly, if at all, visible. Setting the focus would have to be trial and error. No idea if it would work well or not.
Tweakie.
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k thanks :)
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Excellent definition there Lovebee. ;)
Tweakie.
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You need to be wearing protective goggles. Do not look at the reflected beam without them.
If you use a benchtop PSU then providing 2 to 3 volts to the laser control board the laser will emit a LED beam (without lasing) which is easy to focus. Then turn up the wick to 5 Volts. (a DC power source would be better).
Tweakie.
Tweakie,
I found your web page to be full of so much information and humor, (Sorry to Hear About sam 20+ years was bloomin good going eh? Loosing A Best Friend is heartbreaking)
Ok, I have a:
LM-101-A1 - 650nM - 1mW Red Laser
Im trying to cut through black foam, same stuff on your webpage, for RC use and to make inserts for boxes..
The data Sheet Says Input is This:
Laser line dimension 60 degree
Laser line length at 3M 3.5 m
Laser line width at 3M 6 mm
Electrical
Current draw - 20 40 mA
Supply voltage 3 - 5 V
General
Body Brass
Lens Acryl
I have another 2 Lens, one froma DVD Drive, and another from a old Red laser i took apart...
Im trying it on 3v, with a lens infront of the unit, and i can get a tiny tiny tiny point...But no burn on a black surface..
Is 5v Enough to pump out a burning laser? The specs are close to your laser?
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Just to add to the Above, Your A Rc fan, I can Just Use a UBEC 5v/3a From A Lithium pack to give me a clean 5v ....? Right :-S
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Hi Cosha,
I think that using the lithium pack is a brilliant idea, certainly a clean supply (no spikes at switch on etc.).
The laser has to be focused to the tiniest possible dot (size of a pin prick) to be effective but 1mW is just not enough power. You need at least 150mW to be in with a chance but 1 Watt would be even better.
Tweakie.
(I have said this before but please be extremely careful with diode lasers, the beam reflects of almost anything and you must wear protective goggles of the correct wavelength at all times. The wavelength of these devices makes them many many more times dangerous to our eyesight than, for example CO2 lasers.)
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Ah crud, i just machined a nice holder for this aswell! Lookis like im going to have a good look at ebay then!
Im only putting 1.5v through the diode to test the focus...
Im not so advance as to build my own driver for a diode just yet so ill have to look for one complete!
Im guessing the Driver on this board is not enough to power a 150mW?
Iv have started so ill finished :-)
i just spent 2 hours machining too, doh!
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My sympathy's - I have been there, done it and read the book ;D ;D
Dar303's posting here is also relevant to your project http://www.machsupport.com/forum/index.php?topic=16760.new;topicseen#new
Tweakie.
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Sorry, im a part i mean 100mw laser diode, not 1mw
100mW with 5v should be ok, i can get this focused to smaller than a pin prick i think 1/2mm
I just ordered some 650nM glasses from work (i love working for the MOD)
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No, Not working, 5.1v Via UBEC Lights are on, pin point beam - nooo burn!
Bummer!
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Sorry to hear that.
Is the device lasing ?
Are you sure it is not 12 Volt operation ?
100mV is not ideal but you should be able to burn black colored plastic stuff.
Tweakie.
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Manual said 3-5v, i checked the output of the bec at 5.1v 3amp
Yeah the laser is on, i tried wood and black foam, did not even get hot...?
How much does your laser have going in, 12v?
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Great, i have the 1a Model = TUV rated, so i expect there '100mW' is Actualy 100mA Consumption, meh it was worth a try i guess...Not going to spend to much money on making one!
I might buy a cheap one from China Via Ebay, and have another go
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It must be 18 months since I last used the diode laser but from memory it was 10 volts input to the control panel.
Go on get a CO2 tube (ex.MOD), you could do real damage to wood and foam then. ;D ;D
Tweakie.
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After looking at all your kit, i think id pass >:D
Do you mind if i copy your drag knife specs? im just like you with CNC, just a few years behind! and i have been building mine fore 3 years now :-)
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You are welcome my friend, copy anything you find useful.
I have now learned (took a while) that you never stop building a CNC because it is never ever finished - it is just an ongoing project. :D
Tweakie.
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This is true & i love that!
Keeping on the 'Laser' topic...
I have got a 32x speed diode from a cd burner, will the driver i have be enough to poer it? Trial and error?
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Off hand I would say yes, but I have no experience of using a diode which I don't actually have the manufacturers specification for. It is important to know the maximum current that can be used as it is a very fine line between bright and blown.
Can the maximum current be decided by guesswork ? and if so how ? - these are questions for which I have no answer. If the diode cost nothing then there is nothing to be lost by trying or experimenting but some of these diode on eBay fetch real money and I think that 'trial and error' with these would be just plain daft.
Just my opinion but I am not a gambling man and never have been.
Tweakie.
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Meh, nothing lost free dvd drives everywhere at work, im sure i have seen a few blu ray drives too!
Yeah, i would not spend silly money on one, or a few...
Ill just go see how many v's are coming out my unit
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I killed it with 12v :-\
It was almost heartbreaking yet some what fantastic too!
I been looking all over for a 150mw - 200mw laser, or laser diode and board in the UK, alas no luck!
Where did you get yours from? (Pm me if you dont want visable to the world) Hush Hush etc..
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Hi,
I'll help you out if you want! I love lasers! :)
How much do you want to spend to get this going?
I would recommend a red 660nm diode from a dvd-burner and a Flexmod P3. should be relatively unkillable, have wide input voltage, good response ans safely produce about 300mW with good beam. Total cost about USD50-60 or so.
Diode:
Groupbuy on laserpointerforums, very cheap, 5x for 30USD! Good to have spares when you are starting out.
http://laserpointerforums.com/f55/maybe-another-gb-lpc-815-sleds-4-45-300mw-red-laser-diode-53347.html
ebay: http://cgi.ebay.com/650nm-250mw-Burning-Red-Laser-Diode-USA-3-Day-Ship-/280599607076?pt=LH_DefaultDomain_0&hash=item41550a3724
1x for 15 usd, not cheap but ok.
There are many more.
Driver:
http://hacylon.case.edu/ebay/laser_diode/FlexModP3.php
Good choice. There are simpler ones but this is guaranteed to work!
Case:
Aixiz, usd 5
If you cant re-use a burned out one you already have buy a cheap one here and remove the diode and lens.
http://cgi.ebay.com/650nm-5mW-laser-module-3-2V-12x30mm-kip-kay-project-/380297262381?pt=LH_DefaultDomain_0&hash=item588b7bb52d
lens:
Aixiz glass lens. Good beam, cheap. usd 9
http://cgi.ebay.com/Aixiz-Glass-lens-12x30mm-laser-modules-and-case-USA-/280599619475?pt=LH_DefaultDomain_0&hash=item41550a6793
How to mount the diode to the aixiz housing:
http://i255.photobucket.com/albums/hh149/mevalemadre10/fit_diode1.jpg
A basic how to in constructing a high power laser pointer, some good tips there if you are a beginner to lasers:
http://laserpointerforums.com/f51/build-guide-comprehensive-guide-your-first-build-53972.html
Just ask if you want to know anything more!
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Top quality, thanks for posting all of that info!
I got lots to read then at work today :D
Im going to have a look at some broken blu ray diodes today, im sure we have some here at work!
I don't want to spend huge ammounts, i just want to cut some foam and maybe a bit of etching on some plywood
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Im still having a hard time with this...
i got 8 blue ray diodes here, and 11 red diodes...
I can get all the reds to light up, but wont go past the light into the lensing stage - im guessing the drive i have is not powerful enough...
The blue ray diodes i cant even get to light...
what i will say is my soldering skills have improved tenfold over the last 72 hours!
I have added a 'Skirt' to my laser glasses using tape to cover the sides, lasers do infact bounce off anything!
Im having so much fun though!
I really want the blue diodes to work, much more powerful, im hoping to get up to 500-800mw with the coreect glass and focus housing! Alas, it wont be here untill the new year though (Stupid Uk postal services)
If i was smart enough, i would mill a PCB and make my own driver, but im dyslexic and i get too confused with numbers!
Thank god Mach3 does the Gcode for me eh!
merry Xmass all!
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Strange! Maybe I can help you out but I need some info about your setup; what driver are you using, link to schematic?
Bluerays need a higher voltage to lase, what voltage are you running the drivers on?
Laser diode drivers should be constant current so the voltage is not that important as long as it is over the lasing threshold of the particular diode.
A good driver is essential, if you don't want to buy the P3 I linked to earlier check out the die4drive that is made in uk. Not as powerful as the P3 but also a very good drive, I have several in my laser projectors.
I think it has a max current of 1A and the P3 has 4A max current so both can drive a 445 that need about an Amp to lase.
The P3 can be used with 5V for 445 but the die4drive has higher voltage drop and needs maybe 7V to reliably drive a 445 diode.
You write that you aim for 500-800mW of blue, is that a 445nm "casio" diode?
Ordinary bluerays are hard to get that much power out of, the 4x br diode can produce about 120-150mw and the 6x maybe double. I have not tried the 12x, too expensive and almost obsolete now with 445nm for 40 USD.
Sorry for my laser-babbling, hope it will be of some use!
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445nm "casio" diode -
Yes i can confirm this - the only troube is, at work we have a 'parts' bin, with PCs of all different faults, so in this case it could actualy be the unit that does not work! Its all trial and error here...
I dont have a multimeter that will drop down to the mA range to see what sorta output the drivers i have got...
I have ordered a p3 drive that you recomended, and a unit to house it all in with a colimating lens...
i have no drawings of the drives i have got either, but i have a funny feeling the driver i have not got has either a voltage cut off at around 5.8v or a thermal shut down!
Still i have loads of them to mess around with...
Dont worry about the laser babbling, im really enjoying the laser geek things :-)
If i cant get any blue lensing, it wont be the end of the world, a red diode with a burn will be enough for cutting black depron for my needs!
ill check out the die4drive though!!
Got a link where i can see your laser stuffs?
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Ps, im using a stable UBEC thats 5.1v clean