A fantastic watch on a nice snowy Sunday afternoon. Thanks, Russ, for all that you do in regards to the laser teaching! I wish I had a rich sugar mama too lol
I just came across your videos a couple of weeks ago. They are awesome very helpful. I have started watching the videos from the first one and I think I’m up to 60.
I have never been so happy to watch an hour long, as some would say, boring video. I appreciate the crazy amount of time you have put into this testing. Then giving us just the cream off the top, Thank you. I have a stock China blue, which should I spend my money on first; new mirrors or new lenses?
Hi Joel It's worth taking a mirror out and feeling it. If its silver looking and feels "very" heavy, then you will already have (in my opinion) the best molybdenum mirrors. Your stock China Blue will have been supplies with a 2" focal length lens, almost certainly a treacle brown colour rather than an obvious bright yellow. This will be a lens of Chines origin and will again be the cheapest flat on one side plano-convex style. You will find bigger issues with your machine than the lens when you get to understand it a bit more, but if you wish to improve performance without spending buckets of money, an 18mm diameter meniscus lens will unlock the little power that you probably have in your 30 watt tube (claimed to be 50 watts?) www.cloudraylaser.com/products/china-pvd-znse-focusing-lens-for-co2-laser?variant=43422450056. Become friendly and familiar with your new VW Beetle, You will never be able to pimp it up to a Ferrari but there are significant changes that you can make cost effectively to make it into a reliable "fun" thing. Best wishes Russ
Russ you said at the end that we need to use your test program on each material to get good results with pictures. Where can I download this test program as well as the plans for your lens head and ladder? Is there a website repository of those files? I’m very grateful for the hard work you’ve done and I’ve literally spent days watching your videos. Thanks for freely sharing the knowledge.
Thanks Yoni. If someone else is happy to take a commercial risk with the items I design then good luck to him. I might get a few feebies to test, but my major reward comes from knowing that the practical process improvements that I am designing, will be cost effectively available for the wider hobby laser community both now and later when St Peter wants his laser machine fixed!!! Best wishes Russ
I'm curious. If you were able to keep the lenses parrell to each using a threaded ring, instead of an oring, if that would create more repeatable results? Then that brings the question, how many combinations were overlooked because they weren't properly a lined? You do great work sir! Thank you so much for your generosity!
I was thinking the same thing. The results are great, but there's an obvious repeatability problem in the lens mounting that's causing false negatives. This is likely selecting for lenses which are forgiving in their mounting as much as it is for the ideal lens combination.
So if 0.5 of a mm can make all the difference, this prompts me to wonder about your metal table. If it is just sheet metal it would certainly have variations of flatness. It it was machined steel it would be much more even and stable. I was wondering if float glass was actually more uniformly flat. What negatives can you envisage using glass as the surface instead of steel? Also did you know if you use the 'normalise' option on your sound in the video editor, it will give an average sound level across the whole video. This mean your workshop recordings will have the same average volume as the computer recordings. ;) P.S. I LOVE your work and detail.
Hi Ben Glass has the great advantage of flatness and total absorbtion of IR so there will be no reflection from the surface when the beam breaks through your material. It will require quite a lot of excess energy to mark it so in general for a small table 4 or 6mm glass would be good and eaasy to clean with acetone or something less agressive. BUT it's not magnetic and you cannot drill and tap fixing/location holes for fixtures that require absolute positioning.. In reality cold rolled mild steel sheet is very flat over small areas less than 3 feet square for example. My 300x500 and 600x400 machines are both set to better than 0.5mm relative to the nozzle. However, for absolute precision whilst engraving on glass, card and 3mm Baltic birch plywood I designed a vacuum table with 3 point adjustment and edge clamp screws for the plywood see th-cam.com/video/l6VTGRtFY-M/w-d-xo.html This allows me to set the engraving surface true to within 0.1mm. The disadvatage of steel is that it is still about 60% reflective although the slight orange peel effect on the surface has a scattring property which reduce the energy density of any reflections. I appreciate your normalization comment and I have all the pro equipment and pro editing software that allows me to do this. However when I started this series of "look over my shoulder and watch me learn" videos, I made the concious decision to focus on the content and not to do anything flashy with the video. I wanted it to be "as is" but watchable. I could use wireless mics and I have several Rode mics as well but the camera stero mics are what I wanted because the varying sound levels helps to paint a picture of my position when I am not on camera. The varying sound levels and reverb of different spaces paints it's own aural picture There are rarely and zooms or pans, just in-focus tripod shots of the important action.There are no wizzy titles or credits and no adverts because I do not monetize. I enjoy the speed and simplicity of this style of editing because all the artistry has been stripped away. Best wishes Russ
@@SarbarMultimedia Absolutely appreciate your videos. I was just thinking you might appreciate the tip. Normalisation takes moments to do and means the watcher doesn't need to adjust volume mid video. In sound select all then normalisation. Ha ha yes my pet hate, over the top intro splash screens, followed by half baked info. Yours are perfect.
I suspect that is a homemade spatial filter, followed by columating lenses would clean up the beam. It would be silly, but a faraday resonator would go that last little obsessive bit by keeping the reflection from reentering the optical system. Either of these would cost power, the latter perhaps half.
My approach is to keep it simple and within the capabilities of my two remaining grey cells. As I have declared to all, I'm not a physicist.or an optical engineer so my simple question is how will your techno-speak system improve what you see at 28mins? Ball in your court to show us all how to get smaller dots and all within a standard lens tube and no water cooling.. This is not meant as a joke, I really am keen to learn if there is a better way at a reasonable price Best wishes Russ
Well, if the light rays could be made to run parallel, then focus would be less of an issue, though the challenge is: the infared heat light bends at a different amount than visible light, so some kind of calculator might be helpful that can be set for a particular frequency, and of course the speed of light through that material. If you use just a pinhole to block the halo around the beam, it might introduce diffractive effects, depending on the diameter. To me, light going through a pinhole looks like someone blowing bubbles with that little ring. Anyway, that's what a spatial filter does: the light goes through a lens, is diffracted by a pinhole, reforming it, then often lenses are used to columnate the light exiting. Columating in itself might make better spots on any surface that in not dead flat and smooth. I have never seen a laser cutter with a spatial filter, but that would be the end-all of making a nice gaussian beam from a laser. Even dust on the mirrors leading up to it could be eliminated, but that's not an issue with a laser cutter. [If the beam was astigmatic, or oval like a diode laser creates, they often use wedge prisms to make it round, but I doubt that a C02 laser would have that issue.] BTW, I don't own a laser cutter, but I've learned a lot from your channel. Thank you. If they fly model airplanes in your area, they would love to know someone with such a machine.
Many thanks for your explanations. There are quite a few questions that would be better discussed off-line. Sadly You Tube ceased their private messaging system. If you would like an off line discussion, can you add your email to a comment. I will automatically get a Gmail copy and will immediately delete you comment. Best wishes Russ
Russ, your series continues to impress and educate! Thanks for keeping up with it. With respect to dot size, have you seen the reference material on the ii-vi infrared website? They post some equations for estimating spot size given various beam parameters and none of the curves approach 0.025mm. The most interesting thing to me was that the optimal beam diameter entering the final lens appears to be much larger than what it is on the china laser machines, on the order of 25mm, not 8. I played around with the equations in a spreadsheet and had to add a few unit converting constants here and there so that my spreadsheet gave the same answers as their examples, but it is interesting to look at. Cheers!
Hi Mike As I have found, theoretical spot size and practical dot size are two different things. The power distribution within that spot size is still the beam's Gaussian distribution That means I can do damage to materials at dimensions less than the spot size. Theory is only a starting point. As a practical engineer I have always relied on acute observation and practical results. I have spent much time on various optical company websites, including the one you mention, but the most down to earth practical analysis of lenses is to be found at the Parallax Tech website www.parallax-tech.com/faq.htm. Even there they tell me that what I have achieved is not theoretically possible. But then again, there are several things we take for granted with this technology that do not have easily available explanations. I have sent questions to many laser academics and global optics companies in an attempt to get factual explanations for the things I have observed. From those that take the time to answer , I have only had answers of the type, "it's probably caused by this or that effect". I am sure the answers lie buried in academia somewhere but why should we worry because what we have works. My problem is wanting to understand. Many thanks for your comment and pointer. Best wishes Russ
@@SarbarMultimedia Russ, thanks for your reply! The parallax-tech FAQ was interesting reading. Here is an idea, followed up by why: What if you put a beam expander between your laser tube and the first mirror? (Or anywhere it will fit before the last mirror?) As you said, even when focused into the spot, the spot has the same power density distribution as the incident beam, which is nominally Gaussian and goes from nothing to maximum beam power since the entire beam is hitting the lens. If this wolfram alpha link works, it looks like this: www.wolframalpha.com/input/?i=integrate+PDF%5BNormalDistribution%5B0,+1%5D,+x%5D+from+x%3D-3+to+3 At one point in one of your videos, you were talking about reducing the magnitude of the power range across the distribution in the spot. Well, if we were able to slice the tails of that Gaussian distribution off and work with just the center portion, the power distribution would look a lot flatter: www.wolframalpha.com/input/?i=integrate+PDF%5BNormalDistribution%5B0,+1%5D,+x%5D+from+x%3D-0.4+to+0.4 "But I'd be throwing away 70% of my beam power or more doing that," I hear folks saying. And yes, that's true, but it's the 70% of power that you don't want messing up the outsides of your spots or the walls of your cut. And, since I believe the engraving I've seen in your videos is done with minimum power, it seems there is a lot of headroom to increase the power and get the same energy on target even if the outer 70% of the beam is discarded. What I don't know is if the speed of the system will degrade once you're out of that 'pre-ionization / high-impact engraving' power zone. And how do we discard the outer portion of the beam and work with the center portion, which has a much flatter power distribution curve? We expand the beam with a telescope before the first mirror such that only the portion of the beam we want hits the mirror and the rest hits a beam blocker or aperture. Maybe this is all wrong... but it certainly seems interesting, to me at least. Thanks for your time! Best, Mike
@@LikesGadgets Hi Mike Again thanks for the links. I found that this en.wikipedia.org/wiki/Normal_distribution gave a much better visual interpretation if you look at page 4. of my 12.7mm beam diameter 95% of the power is within the central 8mm and if I reduce the diameter further then the central 4mm still contains about 70% of the power. I have tried beam occlusion with no real success, but, before finding this out with some quick and dirty tests, I had anticipated good results, after listening to others advice and looking at the theory. I had prepared a black anozided finned heat sink to fit to the head in front of mirror 3 and it contained a sharp edged orifice that I was planning to gradually increase. The idea was that high speed engraving at 200 to 400mm/s would create sufficient air movement to self cool it. A wasted effort as it turned out. The theory seems to aimed at achieving the smallest SPOT size not DOT size. In the end pushed theory aside and worked towards a magical combination of lenses, lens shapes, focal lengths and differing quality materials. Go back and rewatch this video from 23min 30 to 28min and you will see why I'm no longer interested in theory or expensive additions to the light path. Pragmatic and logical experimentation along with careful observation has won the day. I had spent many months working towards achieving the best possible dots for engraving on wood, card or leather. The Thunder laser claim to be able to achieve a 1000dpi with their expensive compound lens system was the real driver. I was either going to emulate it or prove that no such claim was valid. It has taught me so much and I laugh at their claim now. I also note that Epilog, Universal and Trotec use the half tone(newsprint) technique that Thunder laser used for their photo engraving. I suspect it's again because they cannot produce super small dots. Technically with their rapid responding RF laser they should be capable but they are only using standard single lenses. It's a great feeling that I have dragged my little £1000 Chinese mongrel into another world of performance just through understanding and a few intelligent low cost modifications. Again, many thanks form your stimulating contribution. Best wishes Russ
SarbarMultimedia Hi Russ, thanks for the clarifications. I did re-watch that portion of the video, and as they say, nothing succeeds like success! I think it’s fantastic that you drive all of these questions to ground with actual experiments, and I thank you again for sharing. Some day I will get my laser upgraded and perhaps then I will be able to take advantage of your experience and perhaps learn a few things on my own as well. Cheers!
Hi there. I'm new to the laser world and I need help from you. I bough a laser from a lady, is a 50w Morn and there is no CD so I downloaded RDworks but it wont communicate with laser, I tried calling them, emailed them and nothing, can you please help me? thanks in advance
Hello Russ, Big Fan!!!!.........I have a idea for a session. I have recently hade some mirrors that went bad and a friend told me to make mirrors from hard drive platters.. I made some 20mm mirror that I have to admit works pretty good ..Maybe we are on something here....Secondly , Will the compound lens work with the china blue (which I own ). Thanks for your videos
Hi Brian th-cam.com/video/HHagynL4zqs/w-d-xo.html will answer your platter question. They are ok if you are desperate but better spend $15 on 3 molybdenum mirrors and gain 20% more power. The compound lens system is housed in a special nozzle that has an M22 thread and will fit in place of your existing China Blue nozzle Best wishes Russ
Hi Russ i would require your magic power meter for my bodor laser:) Please send me info on that matters. Im a big fan of your series been with You from the start and cant wait for another tutorial:)
Hi Leslaw Sadly You tube ceased their private message system. I will need you email address so that I can send you a data pack. Add your email addess as a comment. I get auto copied to my gmail so I will immediately delete your email from public view. Best wishes Russ
Hi If you add your disguised email address (johndotsmithatyahoodotcom) to another comment I will send you data.. I will also delete your comment/email from public view. Best wishes Russ
Hello Russ, im a big fan of your chanel. Im jus wondering if you could provide a link for the best combo of lenses so i would not buy something else by misstake. I can put 2 lenses in my existing barrel and would love to try it out. Thanks so much.
Hi Srdan I am not aware of any standard nozzle or lens tube that will put the combo lenses in the correct position. Even my China Blue gold nozzle that will accommodate 18mm diameter lenses, will set the lenses so far back that the focal point will be inside the nozzle. The special lens combination has to be correctly positioned relative to the work face. At present the special nozzle is being manufactured but it could be available in about 3 weeks time. I will let you all know when and give you all the links. Best regards Russ
@@SarbarMultimedia i see well i still have to catch up on a few of your videos regardig the nozzel and the lenses. I just tried nd they both phisicaly fit inside the bottom piece, now if the nosel is to long so that tje focus point is in the inside of it its still to be determined :) ok if thw mounting option will be avaliable in cca 3 weeks id also like to order the correct lens combinations could you be so kind and give links to those? Many thanks.
Hi Srdan I have advised Cloudray to sell a compound lens KIT, which will be a special short nozzle plus the two correct lenses plus a short piece of 4mm diameter air assist pipe. You will also be able to buy the short nozzle and tube as a universal engraving nozzle.without the lenses. One of the lenses I have used is not currently available on the Cloudray website. If you buy the lenses separately I suspect you will pay more than when included in a kit.. The lenses I have used are both 18mm diameter. One is a PVD 38.1mm plano convex and the other is a CVD 63.5mm meniscus . There is a message button at the top right corner of their web page so you will have to inquire about the PVD lens. Best wishes Russ
@@SarbarMultimedia Russ you are really agreat guy. To take so much time and to do these great videos and to reply to people in the manner that you do is really incredible, i believe many people would just not bother. Thanks again and looking forward to your next video to learn something new!
Hello Russ, i made the lens testing jig as you have it to see what is the focal discance of the lens. i made the shelfs go down 1.5, 2, 2.5, 3 and 4 inch and when i put on a 1.5 inch lens its alredy all blury when i put it on the 1.5 inch shelf, i have to lift it half way up to the lens to have it in focus, and the 2.5 inch lens is in best focus on the 1.5 incs shelf, still looks like someting on the 2 inch shelf and on the 2.5 is all a blur. Did i make it wrong or whats the matter that i dont see the right focus on the right shelf. As when i put it in the machine and set it up to the coresponding focus point i get nice sharp dots on both lenses... thanks for your feedback.
Hello I was wondering if you or anyone could help me figure out a potential homing issue on my Chinese laser. It is a 1400mm by 900mm work area. My laser homes to a different position on the y axis between layers. The change varies from 2-8mm. I have adjusted my stepper motor pulse settings for the y axis and it cuts exactly to programmed dimensions (100mm by 100mm). The X axis works perfectly and homes to the same position every time. It appears to me it loses track of it self moving back to the home position on the y axis. Are my Y axis belts potentially not tight enough or is it a software error (RDWorks)?
Hi This may take a bit of back and forth to sort or it may be very simple. First if you look at the top left corner of your RDWorks you will find it will say V8.01.?? The ?? is the issue number. It is currently at 31. My guess is that you have quite a dated version. There were all sorts of bugs in these earlier versions, so first off go to cloudray.oss-us-west-1.aliyuncs.com/Controller/Ruida/RDWorksV8%20Setup%208.01.31.exe and load the latest version. If you are still having issues then add your email address to a comment. I get auto copied to my gmail so I will immediately remove your comment.email from public view. and write back to you. Best wishes Russ
Yes my software was very dated at issue number 10. Thank you so much for the link to the update!!!! It immediately resolved many of the glitches that I just came to accept as part of the software. I will check to see if it resolves the homing issue. Your videos have been extremely helpful as finding directions or support for these Chinese lasers can be very difficult.
Hi Sean You have misunderstood me. I have nothing but 110 % respect and admiration for Lightburn. No there are pieces of software that you can buy from those expensive machine companies that claim to be the only path to photo engraving success and that anyone can use. Are they designed for use with constant power glass tube technology? No. Are they based on the principle of one screen pixel - 1 burnt dot? No. They have basically hijacked the halftone newsprint algorithm and added extra lightening and sharpness to counteract the over burning of pixels. The result is more cartoon-like than photo-like. This is the photo engraving for idiots I refer to. Thanks for the comment because I would not want people thinking I am marking Lightburn down in some way. Best wishes Russ
@@SarbarMultimedia Thank you for the clarification. Big fan of your work. I watch every video you make and was just very confused there for a short while. I remember you gave Lightburn photo engraving high praise at the end of video 136, but it is also understandable that you primarily use RDWorks in the "RDWorks Learning Lab" video series. Of course, I should have understood it from the other videos in-between 136-156 that it wasn't Lightburn you were referring to. Anyway, thanks for taking the time to clear it up. The work you have put into these videos is truly impressive. th-cam.com/video/4IgYMp9Wrqc/w-d-xo.html
Hi Michael If you wishe to add your email to another comment in disguised form ( mike29atgooglemaildotcom) I will send you a copy and delete your comment Best wishes Russ
Hi Wayne There is no possible link between power and speed because these are two completely independent mechanisms within the machine. If you set power to 50% and check the voltage between GND and IN at your HV power supply you should find it will be about 2.5vdc. Now change the speed and it should remain at 2.5vdc. If it drops then you have an issue with something dragging that voltage down. Some machines have separate mains conditioning power supplies for the stepper motor voltage and others use a combined multi output power supply. This would be the next item to check for voltage stability. Best wishes Russ
Thanks for the advice but I think experience trumps theory. I have been using that pair of lenses for over two years now . I remove them regularly and inspect them and clean the lower meniscus lens. I see no sign of damage to the AR coating on either lens at the contact point and there is no loss of performance over that time. They cannot move relative to each other because they are clamped in place with a rubber compression ring. Of all the lens combinations i tested , some with air gaps and some touching, the touching results were always better for the goal I was trying to achieve. Best wishes Russ
@@SarbarMultimedia Hi Russ, I'm not sure what I did wrong then. I bought one when they first came out and it did indeed ruin the 38.1mm lens. It wore a small circle where the 2 lenses make contact and it happened fairly quickly. One of my friends uses a thin o ring between the lenses and has had good results, but I would prefer to use the kit as designed. Any tips would be appreciated, I would love to be able to experiment with the compound lens setup
@@legacymonument206 Just a thought. The top lens is a cheap PVD Chinese lens. Nothing to do with the cost, but all to do with its optical properties. All PVD lenses have an 80 watt limit . This lens is designed for photo engraving at 20 to 40 watts typically . One guy did crack the top lens when he tried to cut 3mm plywood with his 130 watt Reci tube. I have this compound lens on all 3 of my machine ( not all are 2 years old) but am experiencing no issues. I even used it on my new RF machine but that is only 30 watts. Even a small air gap changes the optical properties and creates a scorch halo around the dot. There is no harm to adding a thin spacer, only a change of performance. Best wishes Russ
@@SarbarMultimedia Thank you Russ. I have a 60 watt machine that is set up with a roller table for monuments. When I engrave thin material i have to use a longer lens tube. Its 12" long and I wonder if that causes enough extra inertia to cause the problem. I never go over 300 mm sec and for high quality photos I usually go much slower (75 mm sec) and power is between 7% and 11% when running that slow
@@legacymonument206 That max power should be fine and you may or may not realize that 7% to 11% is probably your pre-ionization zone. That is perfect for all sorts of engraving on glass ,card. wood or mineral materials such as your granite. I remember you telling me that there is a special grade of black granite for this sort of work. The likes of Reci and EFR call this zone "high frequency impact engraving" as though only their tubes are capable of doing it. No, this is a natural property of ALL gas discharge tubes. Just before the beam reaches it's stable operating condition it runs at a random very high frequencies with high pulses of energy . The ammeter will show 2 to 4 mA but those VERY short duration pulses are to quick for the ammeter. This is the zone I use for almost all of my photo engraving work with this compound lens. I am puzzled as to why you are suffering. Your process is producing very abrasive powder, is there any way it is finding it's way between the lenses. The anti reflective coating on both lenses is extremely hard. Cloudraysell silicon sealing rings for lenses or maybe try putting a thin O ring above and below the lenses to try and seal them from the dust environment. How about adding an air pipe ABOVE the lenses to make sure no dusts enters via the lens tube? from several hundred systems that Coudray have sold yours is the first report of an interface issue. The 130 watt guy was a different issue.. This all points to your special application. I suspect the results you get are amazing when it is working. Best wishes Russ
Hi Russ. After seen some of your videos, I did some tests and experimentation. Getting great results.
Thank you for your valuable knowledge.
THANK YOU I enjoy these video you make I learn so much and then I forget so I have to watch again
A fantastic watch on a nice snowy Sunday afternoon. Thanks, Russ, for all that you do in regards to the laser teaching! I wish I had a rich sugar mama too lol
I just came across your videos a couple of weeks ago. They are awesome very helpful. I have started watching the videos from the first one and I think I’m up to 60.
WOW!! Russ. 54 minutes of solid knowledge. I feel smarter already...
I have never been so happy to watch an hour long, as some would say, boring video. I appreciate the crazy amount of time you have put into this testing. Then giving us just the cream off the top, Thank you.
I have a stock China blue, which should I spend my money on first; new mirrors or new lenses?
Hi Joel
It's worth taking a mirror out and feeling it. If its silver looking and feels "very" heavy, then you will already have (in my opinion) the best molybdenum mirrors. Your stock China Blue will have been supplies with a 2" focal length lens, almost certainly a treacle brown colour rather than an obvious bright yellow. This will be a lens of Chines origin and will again be the cheapest flat on one side plano-convex style. You will find bigger issues with your machine than the lens when you get to understand it a bit more, but if you wish to improve performance without spending buckets of money, an 18mm diameter meniscus lens will unlock the little power that you probably have in your 30 watt tube (claimed to be 50 watts?)
www.cloudraylaser.com/products/china-pvd-znse-focusing-lens-for-co2-laser?variant=43422450056. Become friendly and familiar with your new VW Beetle, You will never be able to pimp it up to a Ferrari but there are significant changes that you can make cost effectively to make it into a reliable "fun" thing.
Best wishes
Russ
Russ you said at the end that we need to use your test program on each material to get good results with pictures. Where can I download this test program as well as the plans for your lens head and ladder? Is there a website repository of those files? I’m very grateful for the hard work you’ve done and I’ve literally spent days watching your videos. Thanks for freely sharing the knowledge.
As usual, great info, waiting impatiently to your non-commercial / commercial production with cloudray ;)
Thanks Yoni. If someone else is happy to take a commercial risk with the items I design then good luck to him. I might get a few feebies to test, but my major reward comes from knowing that the practical process improvements that I am designing, will be cost effectively available for the wider hobby laser community both now and later when St Peter wants his laser machine fixed!!!
Best wishes
Russ
I'm curious. If you were able to keep the lenses parrell to each using a threaded ring, instead of an oring, if that would create more repeatable results? Then that brings the question, how many combinations were overlooked because they weren't properly a lined? You do great work sir! Thank you so much for your generosity!
I was thinking the same thing. The results are great, but there's an obvious repeatability problem in the lens mounting that's causing false negatives. This is likely selecting for lenses which are forgiving in their mounting as much as it is for the ideal lens combination.
So if 0.5 of a mm can make all the difference, this prompts me to wonder about your metal table. If it is just sheet metal it would certainly have variations of flatness. It it was machined steel it would be much more even and stable. I was wondering if float glass was actually more uniformly flat. What negatives can you envisage using glass as the surface instead of steel?
Also did you know if you use the 'normalise' option on your sound in the video editor, it will give an average sound level across the whole video. This mean your workshop recordings will have the same average volume as the computer recordings. ;)
P.S. I LOVE your work and detail.
Hi Ben
Glass has the great advantage of flatness and total absorbtion of IR so there will be no reflection from the surface when the beam breaks through your material. It will require quite a lot of excess energy to mark it so in general for a small table 4 or 6mm glass would be good and eaasy to clean with acetone or something less agressive. BUT it's not magnetic and you cannot drill and tap fixing/location holes for fixtures that require absolute positioning.. In reality cold rolled mild steel sheet is very flat over small areas less than 3 feet square for example. My 300x500 and 600x400 machines are both set to better than 0.5mm relative to the nozzle. However, for absolute precision whilst engraving on glass, card and 3mm Baltic birch plywood I designed a vacuum table with 3 point adjustment and edge clamp screws for the plywood see th-cam.com/video/l6VTGRtFY-M/w-d-xo.html This allows me to set the engraving surface true to within 0.1mm. The disadvatage of steel is that it is still about 60% reflective although the slight orange peel effect on the surface has a scattring property which reduce the energy density of any reflections.
I appreciate your normalization comment and I have all the pro equipment and pro editing software that allows me to do this. However when I started this series of "look over my shoulder and watch me learn" videos, I made the concious decision to focus on the content and not to do anything flashy with the video. I wanted it to be "as is" but watchable. I could use wireless mics and I have several Rode mics as well but the camera stero mics are what I wanted because the varying sound levels helps to paint a picture of my position when I am not on camera. The varying sound levels and reverb of different spaces paints it's own aural picture There are rarely and zooms or pans, just in-focus tripod shots of the important action.There are no wizzy titles or credits and no adverts because I do not monetize. I enjoy the speed and simplicity of this style of editing because all the artistry has been stripped away.
Best wishes
Russ
@@SarbarMultimedia Absolutely appreciate your videos. I was just thinking you might appreciate the tip. Normalisation takes moments to do and means the watcher doesn't need to adjust volume mid video. In sound select all then normalisation.
Ha ha yes my pet hate, over the top intro splash screens, followed by half baked info. Yours are perfect.
I suspect that is a homemade spatial filter, followed by columating lenses would clean up the beam. It would be silly, but a faraday resonator would go that last little obsessive bit by keeping the reflection from reentering the optical system. Either of these would cost power, the latter perhaps half.
My approach is to keep it simple and within the capabilities of my two remaining grey cells. As I have declared to all, I'm not a physicist.or an optical engineer so my simple question is how will your techno-speak system improve what you see at 28mins? Ball in your court to show us all how to get smaller dots and all within a standard lens tube and no water cooling..
This is not meant as a joke, I really am keen to learn if there is a better way at a reasonable price
Best wishes
Russ
Well, if the light rays could be made to run parallel, then focus would be less of an issue, though the challenge is: the infared heat light bends at a different amount than visible light, so some kind of calculator might be helpful that can be set for a particular frequency, and of course the speed of light through that material.
If you use just a pinhole to block the halo around the beam, it might introduce diffractive effects, depending on the diameter. To me, light going through a pinhole looks like someone blowing bubbles with that little ring.
Anyway, that's what a spatial filter does: the light goes through a lens, is diffracted by a pinhole, reforming it, then often lenses are used to columnate the light exiting.
Columating in itself might make better spots on any surface that in not dead flat and smooth.
I have never seen a laser cutter with a spatial filter, but that would be the end-all of making a nice gaussian beam from a laser. Even dust on the mirrors leading up to it could be eliminated, but that's not an issue with a laser cutter.
[If the beam was astigmatic, or oval like a diode laser creates, they often use wedge prisms to make it round, but I doubt that a C02 laser would have that issue.]
BTW, I don't own a laser cutter, but I've learned a lot from your channel. Thank you.
If they fly model airplanes in your area, they would love to know someone with such a machine.
Many thanks for your explanations. There are quite a few questions that would be better discussed off-line. Sadly You Tube ceased their private messaging system. If you would like an off line discussion, can you add your email to a comment. I will automatically get a Gmail copy and will immediately delete you comment.
Best wishes
Russ
hi Russ, great as always! So..best combination is 1.5 plano convex ( up ) and cvd 2.5 meniscus ( down ) both with plano side down ? thanks.
Hi Russ sorry for bothering you is it possible to get a copy of the file to make your lens ladder. Thanks again James 🥃🥃👍
Russ, your series continues to impress and educate! Thanks for keeping up with it. With respect to dot size, have you seen the reference material on the ii-vi infrared website? They post some equations for estimating spot size given various beam parameters and none of the curves approach 0.025mm. The most interesting thing to me was that the optimal beam diameter entering the final lens appears to be much larger than what it is on the china laser machines, on the order of 25mm, not 8. I played around with the equations in a spreadsheet and had to add a few unit converting constants here and there so that my spreadsheet gave the same answers as their examples, but it is interesting to look at. Cheers!
Hi Mike
As I have found, theoretical spot size and practical dot size are two different things. The power distribution within that spot size is still the beam's Gaussian distribution That means I can do damage to materials at dimensions less than the spot size. Theory is only a starting point. As a practical engineer I have always relied on acute observation and practical results. I have spent much time on various optical company websites, including the one you mention, but the most down to earth practical analysis of lenses is to be found at the Parallax Tech website www.parallax-tech.com/faq.htm. Even there they tell me that what I have achieved is not theoretically possible. But then again, there are several things we take for granted with this technology that do not have easily available explanations. I have sent questions to many laser academics and global optics companies in an attempt to get factual explanations for the things I have observed. From those that take the time to answer , I have only had answers of the type, "it's probably caused by this or that effect". I am sure the answers lie buried in academia somewhere but why should we worry because what we have works. My problem is wanting to understand.
Many thanks for your comment and pointer.
Best wishes
Russ
@@SarbarMultimedia Russ, thanks for your reply! The parallax-tech FAQ was interesting reading. Here is an idea, followed up by why: What if you put a beam expander between your laser tube and the first mirror? (Or anywhere it will fit before the last mirror?)
As you said, even when focused into the spot, the spot has the same power density distribution as the incident beam, which is nominally Gaussian and goes from nothing to maximum beam power since the entire beam is hitting the lens. If this wolfram alpha link works, it looks like this:
www.wolframalpha.com/input/?i=integrate+PDF%5BNormalDistribution%5B0,+1%5D,+x%5D+from+x%3D-3+to+3
At one point in one of your videos, you were talking about reducing the magnitude of the power range across the distribution in the spot. Well, if we were able to slice the tails of that Gaussian distribution off and work with just the center portion, the power distribution would look a lot flatter:
www.wolframalpha.com/input/?i=integrate+PDF%5BNormalDistribution%5B0,+1%5D,+x%5D+from+x%3D-0.4+to+0.4
"But I'd be throwing away 70% of my beam power or more doing that," I hear folks saying. And yes, that's true, but it's the 70% of power that you don't want messing up the outsides of your spots or the walls of your cut. And, since I believe the engraving I've seen in your videos is done with minimum power, it seems there is a lot of headroom to increase the power and get the same energy on target even if the outer 70% of the beam is discarded. What I don't know is if the speed of the system will degrade once you're out of that 'pre-ionization / high-impact engraving' power zone.
And how do we discard the outer portion of the beam and work with the center portion, which has a much flatter power distribution curve? We expand the beam with a telescope before the first mirror such that only the portion of the beam we want hits the mirror and the rest hits a beam blocker or aperture.
Maybe this is all wrong... but it certainly seems interesting, to me at least.
Thanks for your time!
Best,
Mike
@@LikesGadgets
Hi Mike
Again thanks for the links.
I found that this
en.wikipedia.org/wiki/Normal_distribution
gave a much better visual interpretation if you look at page 4. of my 12.7mm beam diameter 95% of the power is within the central 8mm and if I reduce the diameter further then the central 4mm still contains about 70% of the power.
I have tried beam occlusion with no real success, but, before finding this out with some quick and dirty tests, I had anticipated good results, after listening to others advice and looking at the theory. I had prepared a black anozided finned heat sink to fit to the head in front of mirror 3 and it contained a sharp edged orifice that I was planning to gradually increase. The idea was that high speed engraving at 200 to 400mm/s would create sufficient air movement to self cool it. A wasted effort as it turned out. The theory seems to aimed at achieving the smallest SPOT size not DOT size. In the end pushed theory aside and worked towards a magical combination of lenses, lens shapes, focal lengths and differing quality materials. Go back and rewatch this video from 23min 30 to 28min and you will see why I'm no longer interested in theory or expensive additions to the light path. Pragmatic and logical experimentation along with careful observation has won the day. I had spent many months working towards achieving the best possible dots for engraving on wood, card or leather. The Thunder laser claim to be able to achieve a 1000dpi with their expensive compound lens system was the real driver. I was either going to emulate it or prove that no such claim was valid. It has taught me so much and I laugh at their claim now. I also note that Epilog, Universal and Trotec use the half tone(newsprint) technique that Thunder laser used for their photo engraving. I suspect it's again because they cannot produce super small dots. Technically with their rapid responding RF laser they should be capable but they are only using standard single lenses. It's a great feeling that I have dragged my little £1000 Chinese mongrel into another world of performance just through understanding and a few intelligent low cost modifications.
Again, many thanks form your stimulating contribution.
Best wishes
Russ
SarbarMultimedia
Hi Russ, thanks for the clarifications. I did re-watch that portion of the video, and as they say, nothing succeeds like success! I think it’s fantastic that you drive all of these questions to ground with actual experiments, and I thank you again for sharing. Some day I will get my laser upgraded and perhaps then I will be able to take advantage of your experience and perhaps learn a few things on my own as well. Cheers!
Hi there. I'm new to the laser world and I need help from you. I bough a laser from a lady, is a 50w Morn and there is no CD so I downloaded RDworks but it wont communicate with laser, I tried calling them, emailed them and nothing, can you please help me? thanks in advance
Hello Russ,
Big Fan!!!!.........I have a idea for a session. I have recently hade some mirrors that went bad and a friend told me to make mirrors from hard drive platters.. I made some 20mm mirror that I have to admit works pretty good ..Maybe we are on something here....Secondly , Will the compound lens work with the china blue (which I own ). Thanks for your videos
Hi Brian
th-cam.com/video/HHagynL4zqs/w-d-xo.html will answer your platter question. They are ok if you are desperate but better spend $15 on 3 molybdenum mirrors and gain 20% more power.
The compound lens system is housed in a special nozzle that has an M22 thread and will fit in place of your existing China Blue nozzle
Best wishes
Russ
Am I reading to much into things.. is that Morse Code for rdka on the top line??
Am I close on my guess :)
Great job can't wait to try this with my new head!! Thanks
Great video and great information.
Hi Russ i would require your magic power meter for my bodor laser:) Please send me info on that matters. Im a big fan of your series been with You from the start and cant wait for another tutorial:)
Hi Leslaw
Sadly You tube ceased their private message system. I will need you email address so that I can send you a data pack. Add your email addess as a comment. I get auto copied to my gmail so I will immediately delete your email from public view.
Best wishes
Russ
Great work Russ
Hello Russ, how can I get a copy of your 254 dpi program/file?
Hi
If you add your disguised email address (johndotsmithatyahoodotcom) to another comment I will send you data.. I will also delete your comment/email from public view.
Best wishes
Russ
Hi
Sadly my system will not let me use comcast.net. However, you will be able to download the file from www.rdworkslab.com
Best wishes
Russ
I am trying to find the RD works software. Keep getting spam. Any suggestions?
Hi Jason
This is a pretty up to date and solid issue
www.rd-acs.com/Private/Files/de49e1ea0e9d44aab3ed9724053c7035.rar
Best wishes
Russ
Hello Russ, im a big fan of your chanel. Im jus wondering if you could provide a link for the best combo of lenses so i would not buy something else by misstake. I can put 2 lenses in my existing barrel and would love to try it out. Thanks so much.
Hi Srdan
I am not aware of any standard nozzle or lens tube that will put the combo lenses in the correct position. Even my China Blue gold nozzle that will accommodate 18mm diameter lenses, will set the lenses so far back that the focal point will be inside the nozzle. The special lens combination has to be correctly positioned relative to the work face. At present the special nozzle is being manufactured but it could be available in about 3 weeks time. I will let you all know when and give you all the links.
Best regards
Russ
@@SarbarMultimedia i see well i still have to catch up on a few of your videos regardig the nozzel and the lenses. I just tried nd they both phisicaly fit inside the bottom piece, now if the nosel is to long so that tje focus point is in the inside of it its still to be determined :) ok if thw mounting option will be avaliable in cca 3 weeks id also like to order the correct lens combinations could you be so kind and give links to those? Many thanks.
Hi Srdan
I have advised Cloudray to sell a compound lens KIT, which will be a special short nozzle plus the two correct lenses plus a short piece of 4mm diameter air assist pipe. You will also be able to buy the short nozzle and tube as a universal engraving nozzle.without the lenses. One of the lenses I have used is not currently available on the Cloudray website. If you buy the lenses separately I suspect you will pay more than when included in a kit.. The lenses I have used are both 18mm diameter. One is a PVD 38.1mm plano convex and the other is a CVD 63.5mm meniscus . There is a message button at the top right corner of their web page so you will have to inquire about the PVD lens.
Best wishes
Russ
@@SarbarMultimedia Russ you are really agreat guy. To take so much time and to do these great videos and to reply to people in the manner that you do is really incredible, i believe many people would just not bother. Thanks again and looking forward to your next video to learn something new!
Hello Russ,
i made the lens testing jig as you have it to see what is the focal discance of the lens. i made the shelfs go down 1.5, 2, 2.5, 3 and 4 inch and when i put on a 1.5 inch lens its alredy all blury when i put it on the 1.5 inch shelf, i have to lift it half way up to the lens to have it in focus, and the 2.5 inch lens is in best focus on the 1.5 incs shelf, still looks like someting on the 2 inch shelf and on the 2.5 is all a blur. Did i make it wrong or whats the matter that i dont see the right focus on the right shelf. As when i put it in the machine and set it up to the coresponding focus point i get nice sharp dots on both lenses...
thanks for your feedback.
Hello I was wondering if you or anyone could help me figure out a potential homing issue on my Chinese laser. It is a 1400mm by 900mm work area. My laser homes to a different position on the y axis between layers. The change varies from 2-8mm. I have adjusted my stepper motor pulse settings for the y axis and it cuts exactly to programmed dimensions (100mm by 100mm). The X axis works perfectly and homes to the same position every time. It appears to me it loses track of it self moving back to the home position on the y axis. Are my Y axis belts potentially not tight enough or is it a software error (RDWorks)?
Hi This may take a bit of back and forth to sort or it may be very simple. First if you look at the top left corner of your RDWorks you will find it will say V8.01.?? The ?? is the issue number. It is currently at 31. My guess is that you have quite a dated version. There were all sorts of bugs in these earlier versions, so first off go to
cloudray.oss-us-west-1.aliyuncs.com/Controller/Ruida/RDWorksV8%20Setup%208.01.31.exe
and load the latest version.
If you are still having issues then add your email address to a comment. I get auto copied to my gmail so I will immediately remove your comment.email from public view. and write back to you.
Best wishes
Russ
Yes my software was very dated at issue number 10. Thank you so much for the link to the update!!!! It immediately resolved many of the glitches that I just came to accept as part of the software. I will check to see if it resolves the homing issue. Your videos have been extremely helpful as finding directions or support for these Chinese lasers can be very difficult.
47:15 - Is this a reference to Lightburn?
Hi Sean
You have misunderstood me. I have nothing but 110 % respect and admiration for Lightburn. No there are pieces of software that you can buy from those expensive machine companies that claim to be the only path to photo engraving success and that anyone can use. Are they designed for use with constant power glass tube technology? No. Are they based on the principle of one screen pixel - 1 burnt dot? No. They have basically hijacked the halftone newsprint algorithm and added extra lightening and sharpness to counteract the over burning of pixels. The result is more cartoon-like than photo-like. This is the photo engraving for idiots I refer to.
Thanks for the comment because I would not want people thinking I am marking Lightburn down in some way.
Best wishes
Russ
@@SarbarMultimedia Thank you for the clarification. Big fan of your work. I watch every video you make and was just very confused there for a short while. I remember you gave Lightburn photo engraving high praise at the end of video 136, but it is also understandable that you primarily use RDWorks in the "RDWorks Learning Lab" video series. Of course, I should have understood it from the other videos in-between 136-156 that it wasn't Lightburn you were referring to. Anyway, thanks for taking the time to clear it up. The work you have put into these videos is truly impressive.
th-cam.com/video/4IgYMp9Wrqc/w-d-xo.html
Where can I get the test program you mentioned?
Hi Michael
If you wishe to add your email to another comment in disguised form ( mike29atgooglemaildotcom) I will send you a copy and delete your comment
Best wishes
Russ
SarbarMultimedia could I get a copy of the test program also. Thank you for all the education on these lasers.
hi all when i drop my mc speed to less than 12 mm ps sec the power drops this restricts my material size that i cut is there a solution
Hi Wayne
There is no possible link between power and speed because these are two completely independent mechanisms within the machine. If you set power to 50% and check the voltage between GND and IN at your HV power supply you should find it will be about 2.5vdc. Now change the speed and it should remain at 2.5vdc. If it drops then you have an issue with something dragging that voltage down. Some machines have separate mains conditioning power supplies for the stepper motor voltage and others use a combined multi output power supply. This would be the next item to check for voltage stability.
Best wishes
Russ
Great as always 🥃🥃👍
If you install the lenses together they will rub against each other and ruin the 38.1mm lens
Thanks for the advice but I think experience trumps theory. I have been using that pair of lenses for over two years now . I remove them regularly and inspect them and clean the lower meniscus lens. I see no sign of damage to the AR coating on either lens at the contact point and there is no loss of performance over that time. They cannot move relative to each other because they are clamped in place with a rubber compression ring. Of all the lens combinations i tested , some with air gaps and some touching, the touching results were always better for the goal I was trying to achieve.
Best wishes
Russ
@@SarbarMultimedia
Hi Russ, I'm not sure what I did wrong then. I bought one when they first came out and it did indeed ruin the 38.1mm lens. It wore a small circle where the 2 lenses make contact and it happened fairly quickly. One of my friends uses a thin o ring between the lenses and has had good results, but I would prefer to use the kit as designed.
Any tips would be appreciated, I would love to be able to experiment with the compound lens setup
@@legacymonument206
Just a thought. The top lens is a cheap PVD Chinese lens. Nothing to do with the cost, but all to do with its optical properties. All PVD lenses have an 80 watt limit . This lens is designed for photo engraving at 20 to 40 watts typically . One guy did crack the top lens when he tried to cut 3mm plywood with his 130 watt Reci tube. I have this compound lens on all 3 of my machine ( not all are 2 years old) but am experiencing no issues. I even used it on my new RF machine but that is only 30 watts. Even a small air gap changes the optical properties and creates a scorch halo around the dot. There is no harm to adding a thin spacer, only a change of performance.
Best wishes
Russ
@@SarbarMultimedia
Thank you Russ. I have a 60 watt machine that is set up with a roller table for monuments. When I engrave thin material i have to use a longer lens tube. Its 12" long and I wonder if that causes enough extra inertia to cause the problem.
I never go over 300 mm sec and for high quality photos I usually go much slower (75 mm sec) and power is between 7% and 11% when running that slow
@@legacymonument206
That max power should be fine and you may or may not realize that 7% to 11% is probably your pre-ionization zone. That is perfect for all sorts of engraving on glass ,card. wood or mineral materials such as your granite. I remember you telling me that there is a special grade of black granite for this sort of work. The likes of Reci and EFR call this zone "high frequency impact engraving" as though only their tubes are capable of doing it. No, this is a natural property of ALL gas discharge tubes.
Just before the beam reaches it's stable operating condition it runs at a random very high frequencies with high pulses of energy . The ammeter will show 2 to 4 mA but those VERY short duration pulses are to quick for the ammeter. This is the zone I use for almost all of my photo engraving work with this compound lens. I am puzzled as to why you are suffering.
Your process is producing very abrasive powder, is there any way it is finding it's way between the lenses. The anti reflective coating on both lenses is extremely hard. Cloudraysell silicon sealing rings for lenses or maybe try putting a thin O ring above and below the lenses to try and seal them from the dust environment.
How about adding an air pipe ABOVE the lenses to make sure no dusts enters via the lens tube?
from several hundred systems that Coudray have sold yours is the first report of an interface issue. The 130 watt guy was a different issue.. This all points to your special application. I suspect the results you get are amazing when it is working.
Best wishes
Russ
You are the best! :)
Rabbits chasing dots in a rabbit hole😂😂😂😂