Thanks, Dan.
But the cylindrical attachment keeps the engraved surface at exactly the same distance (focal point) by turning cylindrical items. I don't think it will work for just curved surfaces.
That's why I'm asking. Could you, for example, sit a pistol slide, level, with the rounded top exposed, and engrave the curved surface successfully? I know it can be done, but the engraver I spoke with yesterday said his fiber laser needed surfaces level to about 1 mm. to engrave them.
Bill, I think what you need for that application is more about depth of field, rather than the source technology of the laser beam. The depth of field will depend on the properties of the lens and that will be different from product to product. If I remember correctly when I researched the depth of field for the laser I have, it was supposed to be about 1-2 mm, give or take, so somewhat in line with what you say. But then again the diode laser is much worse at engraving steel than fiber laser (you need a powerful one to make a deep mark), so that may diminish the effect of having nominally larger depth of field. The 1911 slide that I have has about 3 mm of height, so if you wanted to engrave from side to side it would probably not fit in there fully either (but again, I think it will depend on the specific product).
The fiber lasers I have seem have a form factor like this:
So they do not have x-y axes, but they do have a nice Z-axis adjustment - would it not be possible to set the piece down, engrave, decrease z-height, engrave, repeat? The result might be fuzzy, but that could also be compensated for by only engraving the appropriate portion of the image.
The diode lasers I have seen generally do not have z-axis adjustment (though some do), they are mostly setup for moving in x-y. So they would be less suitable for this repeated engraving with z-change.
The cylindrical attachment would probably work if the piece was attached at the appropriate distance from the center, no? It's not the axis of the barrel, but something larger I guess.
EDIT: ah, according to this, the depth of field is 4-6 mm, so it might even work for the 455 nm diode laser (xtool laser). So it might be worth a try with a product like this. But I repeat, the diode laser is bad at engraving metal.
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