RDWorks Learning Lab 79 Machine Health Check Part2
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- čas přidán 5. 10. 2016
- If you own a Chinese laser cutter this little series of videos about me learning how to use the free software provided, may solve the problem of trying to learn from a virtually unreadable manual.
I am nothing to do with RD Works, I am not an instructor and I am no expert. This series will document the essential bits of many hours of trial and error - Věda a technologie
Contrary to your last comments this hasn't been boring at all. I've thoroughly enjoyed being on this journey with you. Good luck with the new copper mirrors which I'm sure you'll purchase. :)
Not boring at all! Very, very interesting and well analyzed! Thanks a lot for the effort!
Excellent series and thoroughly enjoying your attention to detail. Thanks!
Awesome work my friend! I am working on building my own laser system and your insight and documentation on what you have been finding on your journey has been top notch! Your findings will define how my system will be built and maintained. I commend you !
thanks for all of this documentation and information! we are lucky to have you.
I am very grateful that I've found your chanel. So much to learn. Thank you.
You should teach to a school Russ. You have the proper manner to explain things in depth but with a fully understandable way for others to get the point. Think about it mate :)) Having great time watching your videos. Polis
Polis Dimitriadis he is retired lol. Why would he want to go work again? 😄
Thanks Russ - this was another superb lesson which I have learned very much from. Tweaking this kind of machine to that kind of performance is not an easy thing ! keep it coming...
Learning a lot. Information not available anywhere. Thanks.
Russ,
a very interesting video. I was going to make my own copper mirrors before I watched it.
Now I'm thinking about the polishing process in order to get really flat surfaces.
Maybe using my mill (the same as you own) would make a good polishhing machine -I'll have to try.
Another thing: Is the complex pattern you cut into the dark paper available somewhere?
Thank you!
Lothar
I love these videos! I've got 3 of laser machines all Chinese one 50w,60w and 110w. These help me keep them all running sweet! Just wondering would you be willing to do a video on how to engrave a portrait of someone onto wood etc
Hi Jeordan
I have dabbled a bit with wood but nothing serious. The problem with most woods is the grain cuts/engraves completely differet to the normal ringwood. One way to reduce this effect id to convert the picture into dots by a dithering process.
This is an unpublished video I did that might help
czcams.com/video/0C5cizqI8hs/video.html
Best regards
Russ
great info as normal. did you notice that your laser had lost all that power before you thought about making the video. you were correct your paper test is very detailed amazing what you can make either some imagination
You are just amazing! Love your videos and thank you for your time.
I would like to point out one little thing. When you replaced mirror 3 you blew into the hole. Something might get onto the lens : )
Hi Joseph
You get the star prize!!!I did notice my stupidity during the edit but decided to leave it in because I thought people would have "glazed over" by the time we got to that bit
It's good to know that at least ONE of the audience survived that far.
Many thanks for the appreciation
Best regards
Russ
ps There was another mistake in there as well!!!!!!
Hi Russ. Your videos have been really helpful. I just took delivery of a 60w chinese beast and am having problems with the plugs. There are 3 items to plug into the body - the one with the two flat pins (coming from the air compressor) just doesnt want to go in. Do I use brute force or shall I put a UK 3 pin plug on it and plug it in separately?
Hi Doug
There are normally TWO sockets for external connections. One is for the air assist pump and the other is for the water pump. in your case I suspect the third is for a separate extract fan. I know that most of the 60watt machines have these universal sockets. On of the plugs they cater for is the two bladed USA type plug. However if you can't get that to fit it will be perfectly ok to cut it off and put the two wires into a UK 3-pin plug which should fit the universal socket. I would change the fuse to 3amp
Best regards and good luck with your new venture
Russ
I was initially drawn to the idea of doing this as a hobby when the Glowforge kickstarter caught my attention. After reading into the topic, I realized that a more established company and traditional laser might be for me, but those tend to start in the 5k USD range and the sky is the limit. I stumbled across one of your videos and, several hours into it, I'm almost convinced to purchase a Chinese laser and upgrade it. Your videos have been very informative and I enjoy watching you learn as you go. Thank you for documenting everything on video and sharing this experience with us. Have you considered writing a guide book with all that you have learned? I have noticed that sometimes, in later videos, you add one more piece to the puzzle as your understanding evolves. If you were to author a guide book, I can imagine that your latest, most thorough and most accurate information could be condensed into quite a handy reference.
Hi Ryan
Thanks for your kind words.
I still have quite a bit to learn but for a supposedly retired guy I have been very busy with other things just recently. However, I hope to get back to my laser soon and I have a second machine arriving shortly that will allow some interesitng comparisons because it is servo driven as opposed to stepper control. As a completely new and different machine, I will not only include it in my existing series as I continue my learning journey but also run a separate title series dedicated to just that machine. So in a way it will be like the book you suggest because I shall start at square one again and put into more compact terms all that I have learned with my original machine. Much more tutorial and less exploration.
Many thanks for your comments
Best regards
Russ
Thank you l like your videos 😍
Any chance a drawing of the 5 hole meter ? Lightburn friendly
Hi Russ, thanks for another informative Video, Please can you point me in the right direction for getting a Power meter similar to yours, I've had a look and cant see any thermocouple type meters, only the dial indicator types.Many ThanksJames
Hi James
There are digital meters out there but at silly prices. What you see in this video is a design that I have created. I have used a $340 Macken meter to calibrate my laser tube and then used that as a standard power source to design and calibrate my own meter. You may like to check out this video
czcams.com/video/lO9rWlobLZU/video.html
Best regards
Russ
I enjoyed every second of these videos so far. Just a question. Can you cut through more than one piece of paper at a time?
Hi Scott
The problem is air between the sheets. If there is an air gap of any sort there will be smoke created at that interface. Apart from smoke damage around the middle sheet cuts there will be a loss of power as the smoke absorbs the IR energy. On a few occasions I have cut two sheets but only because they have been stuck together.
Best regards
Russ
Mirror distortion. There are some waves in the mirror surface that are not completely focused straight. Each mirror compounds the problem. So after the first mirror the issue is compounded. Having the mirrors turned at the 45 degrees actually exacerbates the problem even further. something that is off by .003 inch will be off by .027 by the end. HUGE difference.
Hi
What worked extremely well with a 5.5mm diameter laser beam falls down badly when the beam becomes 8.5mm diameter. I never even considered this would be a problem when I fitted my new tube. Although manufactured from flat sheet, I don't have proper lapping equipment to make decent flat surfaces, so my bodge attempts were always going to produce "soft" edges. It appears that that curvature encroached on the mirror more than I had expected. As soon as I fired an 8.5mm beam at mirror 1 I was getting edge dispersion. I did not pick this up with my power measurement because I was so close to mirror 1 and all the energy was still being captured. However, as you have noted, the divergance at mirrors 2 and 3 was just increasing massively.I am still convinced of the superior efficiency of copper mirrors that I have a set on the way from China. I think you could see that as soon as I put my old flat moly mirrors back in the machine it was like a miracle. The issue with moly mirrors is 97% efficiency. By the time you lose 3% at each mirror and 3% with a normal ZnSe lens that's 12 to 13% loss( 9 watts of my 70). To get that down to about 5% loss gains me 5 or 6 watts.
The story continues. Thanks for your comment
Best regards
Russ
Thanks Russ. I too believe the copper will be a superior material. I'm thinking that I may do some experimenting of my own with this. I have a very small machine shop with a fairly accurate vertical mill and a lathe. I may even tinker with my little surface grinder and see if I can get a true enough surface to make a set of my own. Never stop learning.
Russ, in 79 pt.1 you mentioned being lost without your kit. What are they and where did you find them?
Hi Russ I was wondering if you could help me please While I am waiting for my new tube I decided to remove the lenses at the front lens as I removed it, it fell into 5 pieces, this means I have to order a new on but there it the problem the lens measures 18mm across, I just dont know which type to go for either glass or copper also does it matter about the dome shape on the lens, Im just confused can you help me please . Many thanks Paul.
Hi Paul
You may be a bit confused about which are mirrors and which are lenses when you look at some websites. !8mm tells me you aree looking for a lens. There are different lens types basical two that are used on these machines. The cheapest and most common are plano convex lenses which have a flat side and a domed side, A lot more expensive but with marginally better focus point are menscus lenses which are domed on one side and slightly concave on the other (a bit like the lenses in glasses) There are also several materials that lenses are made from. The most common and cheapest is a yellow glass-like material called zinc selenide (ZnSe) This material in it's raw state is only 70% efficient at transmitting the laser beam. The other 30% is reflected off the surface by virtue of its crystal structure. To make it work as a lens material an anti-reflection coating is applied. This improves the transmission to about 96 %. There are rather exotic coatings that will improve this transmission to about 99%,. These will be described as HQ lenses and will be about 50% more expensive. Having tried both, the extra cost for a 3% gain is not good value. If you have 40watts going into the lens another 1.2 watts is not going to give you a noticeable cutting gain
To sum up I would buy a normal plano convex ZnSe lens, 18mm diameter.........but with what focal length? The chances are that your machine was supplied with a 2" (50.8mm) lens (the setting piece will have been 19mm wide?) I would suggest replacing like with like , but if you can afford it, I would advise buying a 1.5" (38.1mm) lens also. The improvement in cutting ability will amaze you. Here is a site I have used several times.
www.ebay.co.uk/itm/New-HQ-ZnSe-GaAs-Focus-Lens-For-CO2-Laser-Cutting-Machine-Diam-18-25mm-FL-1-4-/330769086309?var=&hash=item4d035fb765:m:muneiUynaH12_ibMr3Jj7GA
Best regards
Russ
is there any heat build up in the mirror housing as a result of not all the beam contained in the mirror?
Hi Mike
You would imagine if part of the beam was off the edge of the mirror then it would heat the mirror housing. The beam is not uniform power within its diameter. The intensity within is a Gaussian (otherwise known as normal) distribution. Depending on the manufacturer of the tube and the power of the tube the beam could be between 8 and 12 mm total diameter. If you assume the beam is 12mm diameter the numbers are simple. The central 4mm diameter contains about 70% of the power, Between 4 and 8mm diameter there is about 25% power and between 8 and 12mm the remaining 5% power. So you can see that there is no significant power loss or heating effect even of the the beam overlaps the mirror edge by as much as 2mm. There will still only be a very small proportion of the outer 5% power that will be affected..
Best wishes
Russ
Great Video !!! Looking forward to the next one. Saving money to get my own china laser (40 watts seems to be ok for me)
Hi Mirko
Think hard before spending your money The little 40 watt desktop machines are nothing like this unit. They are fitted with a 30 watt tube and there are very few adjustable features and no air assist. Research a lot.
Best wishes
Russ
Thanks for the advice, i think it over.
Well a quick research revealed that a 40W Laser costs about 350 Euro, while a 60W Laser ist about 2000 Euro. No way i could ever be able to afford the 60W one.
www.ebay.de/itm/CO2-laser-graviermaschine-50W-laser-engraving-engraver-schneider-hochprazise-Usb-/272133618743?hash=item3f5c6d7c37:g:KMcAAOSw8w1X8zmw
thx, but still 4x more money for 25% more power...
Hi Russ. Another great exploration. Why do you think that your lens was damaged? Could it be the air assist isn't doing what it should be? Or do you think that there was some impurities in the air that reacted with the lens and laser?
Hi Felisha
In the early days of my machine I did run for a short time with a normal shop compressor but the moisture in the air was "burning" onto the face of the lens. It was cleanable but it made me realize that the little oil-free compressor they supplied did not produce water vapour and I have been using that for a year. Whatever has damage the lens, the mark is not removable. The "up-side" is still pristine so I cannot guess what has destroyed the anti-reflection coating on the work-side. It cannot be fumes because I ALWAYS have air coming out of my nozzle, even when cutting acrylic and the flow turned right down, The other possibility is burning of the lens face from reflections. I have done quite a few stainless steel etching projects and although stainless is not as reflective as copper or aluminium, its about 60%. the size and position of the mark could match up with the hole in the end of the nozzle. When I get my new lenses I will have to inspect the lens regularly to see if I can pinpoint a cause.
Have you tried lasering pattern onto any of your edible treats?
Best regards
Russ
Hello Russ, nice to see you in great condition :)
I have problem with a kind of "mark on the lens" created "by laser itself" as well. Unfortunately I had no time to show you them when you visiting us during holidays. As this is longer story I will make video with explanation, but I have few ideas how to try point out "the murder", or at last - how to found more evidences of crime. And I'm afraid he can be serial killer, as there is a more victims.
Hi Wojciech
One of the problems we experienced regularly when cutting brass and aluminium on powerful metal cutting lasers was reflection damage on the face of the lens. I don't cut those materials on my little toy but I do etch stainless steel. I hadn't considered this as dangerous until I saw the lens damage but I do know that stainless is about 60% reflective and I recognize the damage as a lesser version of what I would witness on more powerful machines. I have new lenses on order and also nice flat copper mirrors from China, so we shall see what happens when all the new kit arrives.
Best regards
Russ
Do you know of any way for me to determine the type of material my mirrors are made of? I've read about several different materials, some of which have coatings on them. And everyone has their own contradictory advice on cleaning/polishing/maintaining them.
Hi Steve
There are a few possibilities for mirror type and it ought to be reasonably easy to identify them. First of all, the colour. If yellow then they are gold coated. Now remember that if you bought an ebay machine then they will be using "cost effective" mirrors, certainly nothing expensive like gold coated copper. The most likely gold mirrors are flash coated crown glass (called K9 mirrors). These are nothing short of rubbish as the gold will almost fall off if you try to clean them. at 2 or 3 times the price of K9 you have silicon mirrors. Again the price would put the possibility of these being fitted at "low". The chances are that your mirrors are silver. That reduces the possibilities to about two types. The cheaper will be aluminium plated with an alloy of cobalt,chromium and platinum. Aluminium is soft and the back of the mirror will scratch easily with a sharp point. The most likely will be molybdenum. It will be natural and polished on one side. A very heavy material (hard to scratch) it can be easily identified by working out the mirror's density. Mine worked out spot on for moly.. It's a hard material that is quite scratch resistant, flat and very stable. Sadly it does not have the best reflectivity (about 97%) but it's a good "all rounder" So in answer to your basic question use colour to start with (moly is nowhere near as silver as chrome plate) and then density and scratch resitance to help identification.
Best regards
Russ
Thanks as always!
I did not see that anyone else has asked but have you tried taking your copper mirrors and with a vise putting a slight curve in them, it seem that your beam is loosing focus and a slight bend in the mirrors should help converge the beam back to more of what is coming out of the tube.
Hi James You are quite right about about beam divergance. Sadly , dishing the mirror is not the answer. When I tested my copper mirrors originally it was with my old laser tube which had a 5,5mm diameter beam. My crude polishing on a soft cloth had the effect of "softening" the edges of the mirror and causing slight non flatness around the edges. . This was perfectly acceptable whilst my beam was small and the flat central part of the mirror was all tha was being used. However, in this video you see something I completely overlooked when I fitted my new tube about 8 months ago was the fact that it had a beam diameter of 8.5mm. NOW the curvature at the edge of the mirror did come into play and caused the outer edge of the beam (where the power density is lower) to diverge.. The main central high density part of the beam was still unaffected (hence the cut was still quite reasonable) but overall there was a net power loss. You are right in saying that the beam must not change shape after it leaves the tube and with my original moly mirrors reinstalled that case was proven. I have just received a set of properly manufactured (flat) copper mirrors from China and will be fitting and testing those in a near future session.
Best regards
Russ
Russ, are you getting consistent measurements? I mean are they repeatable if you don't change anything?
Hi Paul
This is not a scientific instrument but I can always expect better than 1 watt variation. It compares well with the Macken meter.
Regards
Russ
Another great video Russ. Just an update on ,y ,achine I upgraded from 40 to 60w and by god wht a difference. Bit pricey but hey it was worth it. I have a question for you, a bit off topic but can't seem to get round this. I do alot of work and I want to save to a USB Flash DRive so then I can just take the flash drive to the machine and work from there. I have saved it to UFile but wen I took it to machine it says the drive is empty. RD works saves it as an rd file. So where am I going wrong? Or have you not crossed that path yet?
Hi George.
Yes I see this often.
First, are your usb sockets connected to the controller correctly. It has been known for them to be crossed over ie you are trying to read a USB stick with the pc input. You can plug your stick directly into the controller to test it if you need to.
I have a couple of USB sticks that just refuse to work with the machine. Sometimes the connection in the socket is poor and I have to unplug the drive several times to read the file list. I have 3 or 4 USB sticks that work flawlessly. I had a bad Ebay drive that someone bought as a 256gb for next to nothing. When I tested it I found it to have only about 4.2gb of useable memeory but it had been doctored to make it look like a 256gb unit. Even though it will save and reload anything that's smaller than 4gb , the machine refuses to read that.
What I am demonstrating is that the usb drive is a bit fickle.
The other question I must ask is did you load the USB driver when you installed RDWorks? Aso at bottom right corner of RDWorks , there is a box which should read Device = (USB auto)
Hope there is clue somewhere in here to solve your problem
Best regards
Russ
Hi Russ
Many Thanks for that, Truth be told I never thought of trying another USB Stick. So I did and it worked. The difference is that it has to be a FAT32. It will not read an NTFS drive. I also find that once you have it on the USB stick, then on the unit itself you have to copy it to memory as it cannot load it direct from the stick itself which seems to be a bit pintless to me. You could just save it to memory direct tp unit .Cheers again
Hi George
You are correct about the way it works. You have to first READ the USB then COPY to memory. Once the file has copied you pres ENTER. Then press ESC and you will see the drawing building in the bottom right mini window. When it has finished building, press the ENTER key and it will build in the main left screen. You are now ready to START or FRAME. If you press the ENTER button again it will start the ON.SCREEN edit routine which allows you to change parameters for each layer in your program bu using the Z/U button After you have fiddled around with these buttons a few times it will become instinctive.
Best regards
Russ
Have you considered remaking the mirror blocks for mirrors 1 and 2 so you can remove the mirrors like you can on mirror block 3? It would seem to be a much better option. IMHO. lol
Yes better and further than your thoughts See
czcams.com/video/_X1aPY3czYY/video.html
czcams.com/video/HuNZu1-BXuY/video.html
czcams.com/video/RCoTdNJ53dw/video.html
czcams.com/video/jVGByifge_Q/video.html
Best wishes
Russ
Hi Russ, How does the doohickey power meter, i assume its just measuring temperature.
Hi Nick
Watch this and I hope all will be explained
czcams.com/video/lO9rWlobLZU/video.html
If not then ask again.
Best wishes
Russ
@@SarbarMultimedia Thanks
Are you planning to go back to the copper lenses? Perhaps you could lap them on a glass plate with a suitable grinding paste to get them perfectly flat. I've never done lapping with copper, so I can't suggest a suitable paste unfortunately.
Hi Scott
I think I was lucky when I first trialed these copper mirrors. The beam on my old tube was only 6mm diameter and at mirror 1 I think it hit a nice flat spot in the centre of the mirror and there was no beam divergence. With my new tube sending out an 8.5mm beam it seems that it is now impinging on the out-of-flat region around the edge of the mirror that i created with my crude manufacturing method. I'm still convinced that copper is a great way to go and have ordered some PROPER mirrors from China. Watch for another video!!!
Best regards Russ
I have a curiosity question. How do you walk around totally open 60-80W laser without any eye protection at all? You even open a tube, and I see you don’t wear anything.
This is not suicidal stupidity. I have taken time to research and understand the nature of the beam we are dealing with. This laser beam is a beam of invisible light. It is light in the infrared region of the spectrum that our eyes cannot detect. First you must realize that this laser beam is monochromatic, coherent and basically non-diverging . That means that there is no scattering of the light as it travels around the machine, if it starts off as a 6mm beam, after travelling 2 or 3 meters around the machine it will arrive at the lens as a 6mm beam and nothing will have escaped. The light energy in the beam is not in itself dangerous in the same way that a rock falling through the air is not dangerous. Only when the rock interacts with something does the harmless kinetic energy it possesses, change its state to something that is damaging and destructive. It's the same with the laser light When it hits something solid one of two things can happen. If that surface is metallic, reflection will occur. Most metals are in the region of 90 to 99.9% efficient as mirrors. If the surface is non-metallic (ie virtually everything else you can imagine) then the IR light excites the molecules on the surface of that material to a higher vibration state. The higher the vibration state of a molecules the hotter their temperature. When you stand in front of a fire or you are outside in strong sunlight and your face starts burning, it's not because the air is hot it's because the infrared LIGHT that is being emitted from the sun/fire is stimulating the molecules on the surface of your skin to a higher vibration state ie the LIGHT energy is being converted to heat energy on your skin.
This is the mechanism by which the laser beam works when it interacts with the material we wish to damage (cut or engrave). There are many different types of laser with much shorter wavelengths which are more selective about what they will excite. These are potentially dangerous to your retina and you must always wear wrap around eye protection suited to the laser type. Not so with out long wavelength 10.6micron light. As I said, if this light hits anything solid and non metallic it will start giving up it's energy as heat. IF the beam were to hit your eye, it would start heating the surface of you eye (the cornea). That is still dangerous but you must ask, under what circumstances can that happen
Firstly, standing looking at the laser tube as it works is not going to damage your eyes. Without going into the technical way that the laser works, look carefully at your tube and you will see that is is made up of a central glass ionization tube that is surrounded by another glass tube containing cooling water and finally an outer large diameter glass tube that contains the gas mixture. The laser light only exists within the central tube. It is invisible and the pink beam you see is ionized nitrogen (lightening) NOT the laser light. Remember that (with just a few special exceptions) ANY non-metallic material will be heated when the IR light hits it. There are THREE layers of glass between your eyes and the laser light in the tube. Each layer of glass is 100% efficient at stopping the energy so stray laser light will be ZERO. There are just a few special materials that will allow the IR light through. Zinc selenide and gallium arsenide are two materials that are used for lenses and the window on the end of the tube that allows a percentage of the beam to escape so that we can use it to do damage. ONLY if you put you head or any part of your body DIRECTLY in the path of the beam will energy transfer to heat occur. You must not put metal objects in your open laser work area in case the beam gets reflected at you. This is the only risk you must be very careful about.
If you are still fearful, always wear a pair of cheap polycarbonate wrap around glasses
www.ebay.co.uk/itm/Dewalt-Protector-ToughCoat-Impact-Scratch-Resistant-Safety-Glasses-Clear-Lens/262722925484?epid=1040466487&hash=item3d2b81b3ac:g:vB0AAOSw42dZHE3i
If you wear any sort of glasses already (as I do) then you should feel safe without the above.
It is important to understand that not all laser beams are the same as a CO2 laser. Therefore, UNDERSTAND the beast you are working with and take the correct safety precautions.
Best wishes
Russ
SarbarMultimedia omg what an explanation! You are an encyclopedia on feet 😄 thanks a lot. Finally it is also very complete and clear and makes sense. As an engineer I knew good half of this, but the other half totally helped to complete the puzzle. I always wear PC glasses AND keep window closed at all times. I am very tempted to actually open ip the tube and see it at work, but was worrying about potential exposure. Yes, tube is of course protected, but the beam that is coming out right there is not. I do not have a spare pair of eyeballs, so decided to not risk it. Accidents may happen and beam can go into wring direction. Even if this is extremely unlucky, I still don’t have spare eyeballs 😄 But I am gonna open it up now for sure, after watching you playing with it like that. I have a handheld blue laser torch which is 2W and that thing is toxic to eyes, even when reflected, part of the reason is the blue wavelength itself. So after having that torch for quite a while, I taught myself to be very careful with lasers. Even excessively careful, but better overprepare than underprepare, right? :)
Thanks for your explanation, Russ. Invite you to check DIHORSE engraver on amazon. We have showroom in Birmingham, AL.
So, you went full circle and are back where the machine first started then.
Only until I get my copper mirrors from China. I'm sure copper is the magic bullet.
Best regardsRuss
SarbarMultimedia
I am sure you are right and lets hope the mirrors from China are better than that tube was. Btw, who sells copper mirrors from China cheaply as I saw around 25 dollars each.
Hi That's about he price
www.ebay.co.uk/itm/New-HQ-Dia-25mm-Cu-Copper-Reflection-Mirror-CO2-Laser-Cutting-Engraving-Cutter-/161107827318?hash=item2582c65a76:g:XB8AAOxywZ1SNrOi
SarbarMultimedia
In line with what I was seeing at 27 dollars each times three. Too bad we need mirrors at all but with the length of the tubes we do. Still, ~100 dollars for three of them is ouch. I await to see your findings with them. :)
I agree, A bit ouch but I have to know whether the real thing is as good as the promise I saw with my original tests.
hi russ. thank you for all the work you do . i have a little problem with my machine and i was wondering if you could help me. i get a high pitch noise and loss of power but only at low power ..ex when i cut paper..... like this one: czcams.com/video/VFRbJZFMdDQ/video.html .
regards
Hi Axs
Have you watched my video about High Frequency Impact engraving? czcams.com/video/mXIDwQxhX3k/video.html If you are only experiencing the noise at say 4 to 6mA , it's likely to be this zone of uncertainty as the tube is injected with High voltage pulses at 25,000vdc before the beam becomes fully formed whereupon the voltage drops to a stable value of about 17,000vdc I find this is an amazing zone to work in for scorch free paper cutting (on my 70 watt tube I can max it out at 13%power. At 15% the beam is stable . Every time the beam starts a cut, it passes through this zone but it happens so quickly you would not notice it. Shout out again if the video does not answer your question.
Best regards and thanks for the kind words.
Russ
thank you for the reply. very very helpful...still my noise comes from the laser tube psu also......it`s like a sqeeak.....many people on www are talking about a short.... on the red wire or on the other parts of electronics...thank you ...best regards
it was the laser psu afterall...but now the laser just stop working...no beam, no light, no spark ...just little noise from psu when the laser is activated and it supose to cut /engrave.
Hi Axs
Can you tell me if your tube is labelled KH Laser? I'm just collecting information about tube failures and PSU failures.
Many thanks
Russ
yes ..kh laser 25.12.2015
bonjour RUS ceci est le lien de la machine qui me tente......si pas serieuse que me proposer vous dans le meme budget www.ebay.it/itm/162227249013