Non-Planar Laser Engraving

:man_shrugging: I have no idea if this is of use to anyone, but I was just playing around and seeing if I could. Maybe it’d be good for engraving/coloring specific parts of a 3d relief. Might have a go at it myself.

If there’s interest, I’ll see about making a guide on how to do it.

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Definitely curious about this!
Testing gcode ripper for this kind of thing has been on my todo list for a long time already, but never came to actually trying it yet. (http://www.scorchworks.com/Blog/auto-probing-with-g-code-ripper/)

So curious how you did it.

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Gist of was I designed the model seen in the video, exported and printed it to have the physical object. Then while still in fusion, brought it into manufacturing like you would to use the cnc. Which is actually what I did, I simply assigned a 10 degree bevel bit using parallel to sweep the top, setting the feedrate to 1500 (the speed I want the laser), no multiple depths/stepdowns, so one sweep, and 0.2 stepover (for test).

After post processing, I modified the gcode file by removing the G4 dwell, and where the M3 is and put in M3 P20 S51 (copying Luban’s M3 command for turning on the laser at 20%) after it moved into the first starting position. For things with multiple areas, naturally you’ll have to find the retract lines and add M5 and subsequent M3 to keep from burning a straight line, but that’s for a future test.

I’ll go further into depth after I do more tests and maybe a quick guide.

I can really see this being handy on lightly curved surfaces, such as a flask or flat-ish bottles with curved faces (like perfume). You could quickly sketch up a 3d model (or at least a matching curve) in fusion and layer your design on it to match the curve so the laser moves along the curve and never loses focus. Which would be particularly handy for curved stainless steel surfaces, where you want to always be in focus to concentrate the energy.

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Ah, ok. that’s clear and pretty straightforward

My intention was to generate the job for a flat surface and then use a tool like gcode ripper to “wrap” it onto the curved surface.

(assuming I finish my touch probe so I can use it to map out curved surfaces, for those cases that aren’t as easily modeled in F360)

Thanks

Very quick and dirty test as a successful proof of concept. Better designers and CAD users can do much better I’m sure. I shamelessly chopped the head off of Eastman’s Vader bust, squished it to 6mm, milled it, and filled in the eyes. :man_shrugging:

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Thinking about it, I likely should have put this in the 2.0 section.

ok, done. unless you want it in showcase

unrelated you have all the requirements met for trust level 2 except for giving a like

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Nothing really to showcase unless I manage to use it in some awesome project. Sadly, I never really feel anything I make is worth showing off. I’m no designer.

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Really Cool accomplishment @Skreelink !

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For anyone wondering, I re-ran my first test with a colour that actually accepts laser, and this was the result.

I can see non-planar being a bit more useful with the 1.6W laser, since you can remove the shroud and gain more clearance. With my 10W, I only have 9mm, so I don’t have much clearance for curves without hitting the shroud. I have to wonder how a flat fast bust would look 3d printed and ‘laser smoothed’.

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Add me to the very interested list as well. I’m just starting out, and my 10 Watt unit has finally shipped, so great job and thanks in advance if you can create a “How To” guide.

A note for anyone interested; it doesn’t require the 10W laser, and infact I would suggest the 1.6W. For the simple fact that on the 1.6W you can remove the shield for more clearance, and the smaller diameter will help as well. I guess there’s enough interest I’ll see about doing more tests and writing a guide. I’ll use the 1.6W for the guide so people know it works as well.

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Dear Skreelink

Great work. Long ago I proposed to Snapmaker that the strength of a 3-in-one machine was the potential to use the 3 tools in the same object; otherwise, if you have space, you can buy 3 different tools and avoid changing heads and calibration processes.
(oops, just now I realized that this raises some technical issues…)

As an architect, I use Snapmaker to do models of existing buildings that clients can understand, and then propose changes to upgrade them. This may imply cutting or adding parts to an existing model, which I process in CAD/BIM/AAD tools, but in the end I have to reprint it all again.

What you are doing goes beyond my specific needs, and demonstrates that it is not that hard to follow the path I proposed early on: I will try to push this request up.
Meanwhile, while this idea does not go up on the list, count me in for helping with the manual.

Hello guys,

I’ve developed a post-processor for snapmaker 2.0 and I’m on the process of improving it and adding support for snapmaker Original as the spindle speeds supported are different, and other stuff…

On this post-processor (Link below) I’m able to read the retract height from Fusion 360 and with that, I’m manipulating the Gcode to have fast travels of 7000mm/min that are not possible with Fusion 360 free…

And reading this post I was wondering… I think it would be possible to adapt the post-processor to read a Fusion 360 toolpath for machining, then use the retract height to know if the laser should be on or off.
And if the user would input the laser focus distance and the depth of the Fusion 360 machining, I could maybe have a way to output Gcode directly from Fusion 360 to use with the laser head.

Would that be interesting?



Image

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Yes, very.

I don’t think that’s necessary as the machine should already be at the work coordinate origin before running any gcodes, ie at X,Y,Z=0,0,0 corresponds to the laser being at the proper focus distance for a given material to begin machine operations.


Also, that pp is good stuff, thanks for making that. Awaiting your cease-and-desist from Autodesk for bypassing their restrictions lmao

If we set the work origin with the laser on the part yes, but if we CNC a part or 3D print it and then change the tool head, the centers and height will be different… Anyway, I’ll add something like this to my TODO list and will test it properly.

Let’s hope it won’t get that far…

I’d think you would treat it as you would any multi-tool cnc process and your work origin point must be unchanging - a flat spot on the workpiece or piece of tape on the bed or some other known reference that doesn’t change throughout the milling operation. Then you would change to the laser toolhead and focus the laser on same dot used to set the tool height reference for milling. Now you’re all set and laser operations commence based on the same origin point.

There’s many ways of making this work though. As long as you can identify a feature on the milled surface you could of course also use that a the origin point to set future operations, cnc or laser, as long as you can precisely align and set the height.

Regardless, the main difference here in process is this is a reference being directly measured off the workpiece itself or something physical to set the machine origin. You wouldn’t need to type any numbers into fusion for thickness of material or toolhead offsets or whatever.

Yes, in this case all would work ok. Except the fact that when we engrave the tool goes inside the material and the laser stays on the surface. Maybe this should be taken in consideration. Not sure.
Anyway, what would be the Fusion 360 machining type used for this?

Not necessarily true as you’ll need to create some custom tools to represent the laser so F360 knows the laser geometry. I’d probably model the laser as a .1mm endmill. I guess if you model the length of the tool to match the focal distance of the laser then that simplifies several things. I wasn’t originally planning on that, but now I think that’s probably the best - each person creates or modifies the length of the “endmill” that models their laser.

As long as your stepover matches your laser kerf (approx .1mm for the 1.6W) I don’t think it’s terribly important as each spot will be visited once. A 2D or 3D adaptive would likely do fine. 3D parallel would likely result in the best surface finish though.

https://help.autodesk.com/view/fusion360/ENU/?guid=GUID17CC1F90-A2A5-4CC3-80EB-B7972E327E0F

You must have seen the 10Watt laser has a focusing element for distance measuring. I know the height above workpiece is troubling, but assuming the z-change wasn’t severe or over 20mm it might be okay. I want to surface map my object, then ideally setup a bed offset mesh grid like 3d printing, and just fire normal gcode files that use the auto-leveling mesh. This would allow simple 2d files to operate on non-flat surfaces which is what the average user would use and removes the limitation on fusion or whatever software.

I’m sure the firmware would need modifying to accept smaller grid size with almost infinite point density (or 1000x1000 rather than the 15x15 currently), but my use case was the back of a spoon including handle, so it’s possible 15x15 would be enough if I could reduce that to being spread over a smaller physical area (35x150mm for example) than 330x350mm or whatever.
Just about to go and play with g-code ripper, but my real issue is the measuring. I’d love to know the g-code for do distance measure on the 10w, then could start using as a probe at least.

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