Grayscale not engraving

hp glasses
I have attached the vector image i had used. I hope that helps you out.
Also I just want the picture in a good resolution that i can engrave it in. I dont speak with the photographer anymore who took the picture. Also should i stick to trying to do just smaller engravings? any ideas of what i can do in greyscale

@Rainie, @hyeii, @JKC20 and @Edwin
I have emailed customer support several times with no luck. Any idea when I’ll get a reply? Or why I haven’t?

OK…

  1. I have downloaded the vector image and run it through Luban. It is engraving as we speak so I will send you the image and the file as soon as it is done - you may have to wait an hour, I am cooking the family meal right now. I will include the file settings too so that you will see if your machine is the issue.

  2. Not having a better sized imaged is a little awkward but not impossible. I will see if I can make it big enough for engraving onto a square of plywood or similar. This will take me some time. The issues around engraving pictures really are many. I can start to see how we can address those issues after I enlarge the image, if it can be done without destroying the image too much. The jpeg file format is a destructive format and everytime the picture is saved, a little more detail gets lost because the compression algorithm is designed to look for pixels it can throw away so that it can compress the file when saving it.

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They may be short of staff right now… I have not seen any of those names in the forums recently.

So what’s the best file type to save a picture as? My father in law is a photographer so if I need I can get him to change types.
Also while my laser is down any good beginner cnc ideas or gcodes you want to share? Well 3d also. I’m just trying to stay busy.
Thanks for all you help by the way @jepho

Also I was at 34mm to focus on the z axis

A non destructive format that retains as much of the image information as possible because it leaves room to adjust the image in post processing and not remove the detail. If your father in law can shoot in RAW format that will be just fine. He may not be able to do that so next best option for me would be a 16bit .tif file. Failing that a .png file. I prefer an image file with the highest detail and the file and image size should be left just as it is when it is in the camera. If he cannot manage a 16bit .tif file then an 8bit .tif file or a .png file will be ok.

When it comes to sending me the file, you may have to use a free file sending service because of the memory that it will occupy. I don’t use any of them but I know that they are available. If you have a service like dropbox, you could leave a file there and send me a link.

The crucial thing with CNC is not forgetting that the bit is revolving at 19,000 rpm and can do a lot of damage to hands if you do not take care. Clamping is important because you do not want your workpiece to move and the forces generated at the cutting bit can move pieces of wood quite easily.

I have not done any 3D printing because getting it right can be frustrating for users who are quite well experienced and I chose to concentrate on laser and CNC work. I can point you to some good CNC video presentations so you get a clear idea of what it can achieve.

I have been trying to keep the detail in your family image and enlarge it also. It has been pretty difficult because there is so little pixel information in the image.

OK, that is good to know. :+1:

Now you only have to jog the head along the Z axis for any laser work. You place the head against the workpiece using the piece of paper and jog 10mm x 3 and 1mm x 4 so that the point of best focus is always set without you having to make a new set of focus settings for every piece of work.

I actually bought the Snapmaker for cnc work but have found it difficult to master. I then went to 3d printing and have had some success and some failure.
I would love some ideas for cnc. Especially if there is a gcode involved.

Some preliminary testing of the .svg file. I see nothing wrong with the file and my tests show that it is the settings you have made that are responsible for its appearance. I ran two tests at different power settings and densities. You should remember that my laser is 1600mW and your 200mW laser will need different settings.

Here are two test images made on 2mm plywood with Luban software 3.8.0

  1. 100% power single pass density of 7 speed 140mm/min (no dwell time set)

This image is far too dark and the edges are scorched around the pattern. There is a lot of smoke staining too. The depth was set to 0.5mm and this is the depth that was cut/burned. You will not in the enlarged version how the edges of the image are completely fried. So the conclusion is too much power or not moving the laser module or the workpiece fast enough.

  1. Enlargement of 100% power cut.

  1. 30% power single pass density of 7 speed 140mm/min (no dwell time set)

The 30% power cut has much cleaner edges even though it was cut at the same speed. On this basis I would try 40% power, up the density to 10 and try again. In some respects, I prefer not to add to the density setting because this will add more time as it burns more lines closer together.

This is not really interesting just yet but I have another couple of tests running. One is with different software and I suspect that the results will be easier on the eye. One more Luban test will be at 45% power with a density of 7 and the same 140mm/min to see how that works.

That’s awesome. I have done a few more items and there seems to be a little burn on them

OK, as I suspected the other software is better… the Snapmaker runs quieter and the results are so much better.

This image of two burns says a lot about Luban. to keep within the 98mm square 2mm plywood borders, I set the size of the .svg file to 85mm in Luban and Lightburn. The Lightburn image is on the left and it is much larger than the Luban image, despite both being cut from exactly the same .svg file. The Luban image has a lot of smoke staining but the cut is reasonable. It has a much neater edge than the file you showed at post 21 and I enlarged in post 22. My conclusion there is that the wood was very open grained and this caused the image to not look particularly clean.

The Lightburn image has filled as much space as it can with the 85mm square image file and the cut is much cleaner. There is a small amount of smoke staining but I think that could easily be removed by moving the laser a little quicker.

The Luban image was cut at 45% power and a density of 7 with a workspeed of 140mm/min and a single pass. It was cut in just over 1 hour.

The Lightburn image was cut at 75% power and a speed of 306mm/min with two passes. It was cut in a time of 30 minutes.

For my money, it is no contest. The Lightburn image is better in every respect and would not require much tweaking to improve it and cut it in a single pass. I would leave the power where it is and add another 150mm/min to the speed of the cut. This would be to reduce the smoke staining seen.

The Lightburn density setting is a lot more complex but I set it to 100 lines per inch. It could stand being a little higher at 150 lines per inch and that would eliminate the horizontal lines you can see. Lightburn cost around 60 dollars but you can try it free for 30 days. I have been writing a little about it since I discovered it. It appears to be much kinder to Snapmaker and I love the files it produces. It looks a little more complex than Luban and takes a bit of learning. It is very well documented with lots of tuition videos as well. It is designed to run any type of laser machine.

You can read a little about it here:

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Great tutorial that you posted. I have tried a few different types of photos with better success.
With lightburn, can I add regular photos to be burned?
With CNC is there a software you suggest to start with?

Not to take from your insights, but it would be illustrative to use the same settings on both pieces of software.

I haven’t finished reading in detail but I just wanted to give a major league shoutout to @jepho.

Unbelievable work - you win the community award! I know I’ll benefit when my time with the laser module comes around!

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Hello Onno; It is just apples versus oranges my friend. The density of dot in Luban for an .svg image can be set anywhere from a value of 1 up to and including a value of 20. This sets the burn to lightly fill a shape all the way to blackening the whole burn area inside that shape. Lightburn permits a density setting in lines per inch (LPI). It is a sort of halftone screen and can be set from a value of 1 all the way to a value of 2000 LPI. A good general rule of thumb is that the dots per inch (DPI) count of a photograph should be double the LPI used to screen the image. This ensures an appropriate match between the image resolution and the mechanical printing process.

I don’t think it is a worthwhile pursuit to calculate Luban’s 20 points of density and try to find an equivalence in Lightburn’s LPI. The comparison was always going to be more a feature comparison rather than a precision comparison. Why do both softwares turn the same file at the same size setting into two different sizes? I have no immediate answer to that question and once again, it is beyond the scope and largely irrelevant to what I was trying to illustrate to Francis.

For clarity I am posting an image of the settings in Lightburn that relate to the density of the filling of an enclosed space within a design.

I used a setting of fill + line (I could have used fill or flood fill only or just line only) Workspeed and power of laser beam are what you would expect to be able to set. I chose a bidirectional fill because it is quicker and I could have chosen a crosshatch fill. I also overscanned the design by 2.5%. This permits the laser to switch off as it leaves the design boundary and on again as it approaches the design boundary. It provides consistency by accounting for velocity changes when the laser beam head slows down, accelerates or changes direction.

(at this point the facilities and control are already considerably different to Luban and we are still only discussing controlling the burn rate and type)

Line interval and lines per inch are interdependent and you can set one or the other to achieve the same endpoint. Scan angle is simply to determine the direction of any scan lines on your design.
Ramp length for inner and outer edges can be set. Used for setting a slope on the edges for rubber stamp making. Pass number and step is self explanatory. How shapes are filled. I like the individual shapes to be filled as in my owl demonstration in a recent post. Line settings can be different again from fill settings. Where there is a case for using variable power settings, you can set minimum and maximum power outputs.

The forgoing underlines why I did not choose identical settings… the same file was sized differently in each application and no meaningful density equality could be derived.

Thanks for your kind comments, Aaron.

It is just a start, Francis. There is quite a lot more to come. I am still learning the Lightburn software. Lightburn has very comprehensive options for cutting photos. I have not yet done any more than just played with a couple of settings to see what effect they produce.

Unfortunately Luban CNC is just alpha software as they proudly announce every time it is loaded. It is completely inadequate and not worth attempting to learn because it will leave you mightily frustrated. For CNC software with excellent tutorials, I can highly recommend Carbide Create. It is free to use and is supplied with Carbide Shapeoko CNC machines but you can use it without a Carbide CNC machine.

These tutorial video presentations are short and will take you through all of the basics of running the software. I have used Carbide Create to talk to my SM1 and it is a real pleasure to use.

So do you think I’d be able to get pictures done in lightburn? I’ve tried several different formats and they still don’t work.
Also thanks for the cnc advice. Do you know of a good cnc gcode site to start off

Yes, you should be able to burn the right kind of images in Lightburn. Image manipulation needs a bit of photographic knowledge. Lightburn will help but the image format and the settings need to be aligned to each other. If you have any reasonable images that are sized for printing (300 dpi) and a minimum of say 4 x6 inch, if you send me the image, I will do what I can to get it printed from Lightburn. It has ten different modes for image reproduction to say nothing of turning the image into a line drawing and tracing it or making the file and .svg file.

CNC ideas may be found here at Instructables:

Another good place to look is Thingiverse: this for .stl .pdf. dxf and .svg files. the hyperlink should bring you to some wooden items.

Edit to add:
You may need a .stl to GCode converter if you pick up much from thingiverse. This link details quite a few free ones.