3D dynamic focus laser

[Kristian Matz]

I have started researching Fiber Galvo machines (again) and I came across a this machine https://rayfinetech.en.alibaba.com/product/60599431564-800667586/3D_dynamic_focus_laser_marking_machine_for_curved_ surface.html

Does anyone have any experience with this? Are there any downsides to this over a standard galvo fiber machine?


We engrave a lot of curved surfaces and this seems like it would help with items that are not completely flat.


Also if anyone has any suggestions on where to buy a machine from that would be great.

Thank you

[Kev Williams]

I read thru that entire ad, and had my browser search "dynamic'- the only places it found it was in the ad headings. There's no mention of any sort of 'active' or on-the-fly focus mechanism, and the only other focus mechanisms I see in the pics are the hand crank, and the seconary red-light pointer.

If you're going to be doing curved objects, the only viable way I've found is to split apart what you'll be engraving and figure out how much you'll need to raise or lower the work to meet the focus point. Text is easy, just pick which letters to be engraved at each level. Graphics can be tough if there's few or no separate segments. And it's all a compromise, and the whole operation should be 'test driven' on some tin foil because whenever you raise or lower the table, the laser's engraving position changes- raising the table shortens the actual span, lowering increases the span.. This means the next section's text may be spaced closer or farther than it should be, or the horizontal positions may not line up. For slightly arced items is usually not all that noticeable. In some cases adjustments will need to be made. This is when the pointer is your friend by boxing portions of the last engraving after moving the table to make sure it's still where it was :)

Anyway, these are strictly 2D machines.. why mfr's and/or sellers keep throwing "3D" in the names of machinery that the only 3D part is the machine itself, just baffles me...

[Kristian Matz]

I found these videos on youtube:

https://www.youtube.com/watch?v=PfNDP5WC2Os

https://www.youtube.com/watch?v=3PHW4YN6AN8

https://www.youtube.com/watch?v=3PHW4YN6AN8

https://www.youtube.com/watch?v=DmBtyY34dgk

I am not sure what is going on here...

[matthew knott]

You can get galvo machines that have dynamic focus , but the one you linked to is not one! The downsides are they cost much more and are harder to program !

[Kev Williams]

so that's interesting-- since nothing outside is moving, there must be a moving 'first' lens somewhere within or behind the scanhead to alter the beam focus before the main lens does the final focus--

Anyone know how it works?

[John Lifer]

Since going to take a look at the link, one of the other offerings was a Cyclops, has a camera that is connected to computer that supposedly replaced Kev's RED Pointer.
Anyone have any comments about that? I'm leary of getting one if no one has experience with it as I'm not a good guinea pig.

[matthew knott]

Exactly right Kev , you can have 2 kinds , some use post objective scanning ! But basically you have a motorised set of optics before the scan lens ! The best systems stop the need for a scan lens at all , google keyence laser for a run down!
The cyclops is a webcam that looks down on the part and displays the image on the software screen! I prefer a red pointer but it can have its uses !!

[Kristian Matz]

Ray Fine is quoting this as a $10,000 option...

maybe on my next one :)

[David Somers]

Kristian,

I had looked at this when you first posted, and then again today when I actually had some free time. On the first look it was not the machine that came up first that seemed to have the dynamic focus, but another fiber machine that came up further down. Today though I did not see that second machine.

If it were me looking at this seriously I would contact their sales person, Blanca Yan, at yanblanca@yahoo.com. She has been a good sales person (I own two Ray Fine Machines) and been very honest with me. I don't have a fiber though and have never used one so I have no clue what the state of dynamic focus might be in these machines. What I see superficially when looking at that first machine is a fiber laser that perhaps has autofocus on it, with a rotary device. That doesn't seem consistent to me with the title of 3D dynamic Focusing. The term 3D isnt what catches my eye. Dynamic Focusing does.

Anyway....check with Blanca. She can give you the scoop on that feature and the machine(s) it works on.

Also, one other thought....while I see a lot of folks in western businesses being reallllllllly loose with the concept when using the term 3D (Glowforge comes to mind) for what is really a 2D device, with Chinese companies I am less inclined to think of their wording as deliberate deception. It might be of course. But I have seen enough translations done by them to suggest that many times they are simply using the wrong words when they translate things in their advertising and manuals. And to give you some perspective on me....because I have dealt with Ray Fine and Blanca specifically I may be inclined to give a lot of leeway to Chinese companies based on my very good experiences with Blanca. To take this thought further, if you do work with a Chinese company be sure to go back and forth a few times on each major concept, verifying what you each are saying to each other. The translation issue can really mess up both of our thought processes and expectations. Think in terms of psychologists who always encourage people to paraphrase important elements in a conversation to insure you are both on the same train of thought. For example, I could see them thinking that by using a rotary device to engrave a cylindrical item that you are engraving something that is 3D. Hence 3D in the claim.

And of course, if you dont mind please let us know what you find!

[John Lifer]

It actually showed up on an 7-8K machine, but I'm not going to guinea pig right now, just pulled trigger on plain 20w fiber from Blanca.
I'll figure out EZcad at some point!

[David Somers]

Hey John!

I also found it shortly after my post. There are a series of them wayyyyy way down the advert. I have no idea how good it is. Anyone interested should talk to Blanca about what its realistic capabilities are.

7 to 8k is not bad though. Much as I would love to play with a fiber, without a good plan and the time to use it a fiber is not in the cards for me. Maybe someday.

[Mayo Pardo]

Several of the videos that popped up in the Youtube side bar showed this dynamic focusing concept from at least 4 or 5 different company names. What disturbed me the most though was in a lot of the videos people were engraving with no enclosure surrounding the objects and no safety glasses. Wouldn't a curved reflective sphere send that beam off in all sorts of directions? Or does the nature of that kind of laser make that unlikely?

[Kev Williams]

Wouldn't a curved reflective sphere send that beam off in all sorts of directions?
From experience--

Y E S !!!

A few years ago I caught my mustache on fire with my LS900 while it was Cermark engraving lengthwise, but on the downslope (facing me) of a 1.5" diameter stainless tube. My face felt like someone just hit it with a 2000w heat gun, only minus the air- that is definitely a different experience! then I smelled hair burning... Lesson learned--

And one day while trying to learn the fiber's rotary, I was test engraving a small stainless tube-- on one test I forgot to turn the rotary on, so the machine just engraved in flat mode and didn't turn the rotary. I was standing there watching it and as the beam hit the downslope I got that same familiar blast of heat- fortunately I WAS wearing my glasses.

So, yeah- if anyone gets one of these, beware the reflections!