Hrmm. I have Ti. But no laser. Guess I am going to have to wait till Dec. to find out.
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This is the jeweler’s goto source for Titanium and Niobium in small quantities.
Not the cheapest but the material is consistent and they provide great surface finishes (Ti is super hard to get nicely finished with standard tools and chemicals).
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How did it work? I mean how did the markings “come back”. Did you scrape off some of the base metal, but the Ti oxide went deeper, or were you leaving a residue from the scraper.
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What he means is he THOUGHT he was scrapping the mark off the Ti when in fact, the mark was scrapping pieces off the the metal scrapper.
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I was thinking this too! If you could experiment enough to know what temperature produced what color, I wonder if you could split your image into separate bitmaps for each color rip and run them.
It would be much like old conventional printing if it worked!
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Curious if there would be a way to leverage the 256 levels of greyscale into a psuedo-color-image generator. Then you wouldn’t need seperate bitmaps, you would just need to know which greycale values corresponded to which color and adjust your image accordingly.
I don’t know if the oxidization colors can really be controlled like that, but it would be pretty neat it they could.
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It would be great to have really full color, but even with only a few colors you could probably dither your way to something cool. (And a GF has a small enough dot that halftoning wouldn’t look too ugly.)
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I wonder what could be achieved with a controlled atmosphere. I would expect the level of oxygen to affect the color depth of oxides, but probably not as much as temperature.
Controlled shading would be very cool!
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absolutely! Even if it was just a vague “around these values you get blueish, and around these values you get reddish”
hmm, blueish and reddish… Anaglyph 3D images?
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The colors are very predictable when anodizing, but if you are heating (i.e. with the laser) then it gets a lot more complicated. The thickness of the material, the specific alloy, and other smaller contributing factors all mean you would want to do a lot of testing.
I have colored Ti with a plain old propane torch, and it works but is really hard to control.
That said, I think it is possible with a few caveats:
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The temperature difference between colors is sometimes small and definitely not linear.
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The colors you get are what you see in a white light spectrum, and there are some (like a true green) that are really hard to achieve.
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I was wondering if the thickness would be a factor, but that piece was somewhere in the neighborhood of 1" thick, so I’m kinda guessing that it may not matter much.
I wish I could do more testing, but I won’t be able to for at least a week. 
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Sounds as if a test patch might be the way to go, at least for any new thickness/shape/etc. Now here is where I wonder about how open the GF toolchain may eventually be. Because it would be really great to be able to write a script that sits somewhere inside your workflow and takes a picture with the camera, analyses the resulting color/brightness, then rewrites the mapping from line colors or whatever in your design to power/speed levels. Getting GF Central to do that would be hard, but with the right hooks, any sufficiently persistent idiot could do it themselves.
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Yeah I have only ever messed with thin sheet material and wire. I can imagine that if you have big thick slabs to work with then the difference between 1" and 2" might not be noticeable (except to your wallet).
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Hmm… while straight titanium would be pricey, I wonder how thick the layer needs to be to properly oxidize and not harm anything under it? Would a very very thin layer work? Given the color possibilities I’m wondering if it would be feasible to make a titatium-on-something-else sheet that would be a cost-efficient way to get the effect. Perhaps a titanium foil bonded to aluminum, or steel, or acrylic, or even sputter-coated on glass?
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So my lovely picture may turn out to be a Warhol?
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Good point.
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Wish you had a Glowforge to test that out… wait a minute 
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It makes sense that it would work (since it’s a very thin surface effect). But you’d need a very uniform attachment to the backing to get consistent temp at the titanium surface. Or maybe that would be your source of color change.
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Somewhere here on the forums there was a thread about people getting samples of an architectural material that is a thin coating of Ti on stainless steel.
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A quick search reveals two architectural-supply firms that warn this stuff will be expensive. And on alibaba, a bunch of suppliers of various kinds of TI-coated steel, but mostly with minimum orders of a ton or more. Clearly an opportunity for someone to make a market…
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