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At work, we give Cliff’s Klein bottles as the quarterly award for engineering excellence. When I ordered the first batch, I called the number on the Acme Klein

At work, we give Cliff’s Klein bottles as the quarterly award for engineering excellence. When I ordered the first batch, I called the number on the Acme Klein bottles website to ask whether they could be engraved (the site states the CLIFF won’t engrave the bottles but I wanted clarification if ANYONE would engrave them). It rang and went to voicemail. I started leaving a message with my question when suddenly there was a lot of noise as the phone was picked up (apparently it was a real answering machine) by someone shouting “don’t hang up! Don’t hang up!”. It was Cliff. I was briefly star-struck, told him what an influence The Cuckoo’s Egg had on me when I was younger, and then received a 15-minute oral history of engraving methods and why none of them would work on his Klein bottles. An absolute highlight of my year, and I think they’ve been well received as engineering awards...even if we have to use a label-maker to add the recipient’s name :)

driverdan 7y ago
Did he say why laser engraving wouldn't work? I can see the curves causing some distortion but you should be able to compensate for that. Edit: He answers the question in his FAQ > The borosilicate glass laughs at laser beams ..which makes sense. Seems like sand blasting would be the best way.
- CliffStoll 7y ago
  In short - engraving borosilicate is difficult, because it does not expand very much when heated. So when hit by an infrared laser beam, the glass doesn't locally expand and spall off a tiny speck of glass .... instead, the glass locally melts. When the beam moves on to the next pixel, the first site either solidifies or sometimes dribbles away. Laser engraving of borosilicate just doesn't work well. And, because of the compound curves of the Klein bottle, you need a big depth of field as well as a rotary bottle holder. All laser engravers that I've played with have a very short (10mm or so) depth of field. Diamond engraving doesn't work well because of the curves. Sandblasting with a rubber mask works, but making the mask is a pain. So, after lots of attempts, I've given up on engraving these guys. Also: mistakes are expensive -- this is hand-blown glass.
  - dlgeek 7y ago
    (Everyone should make sure to note the name on the above comment) Thanks for answering, and congratulations on your book's anniversary. My job gives out copies of your book as a somewhat prestigious award to those who find and report security problems, and I'm very happy to have both received and read a copy.
  - numlocked 7y ago
    This is basically exactly what you told me on the phone :) We also had a fun digression about sand-blasting tombstones. And of course, we covered the hand-engraving/dremel option. So...label maker.
  - pmoriarty 7y ago
    Can't acid be used to etch glass? Also, why not use glass that's easier to etch?
    - wnkrshm 7y ago
      With quartz glass, it's going to be hydrofluoric acid and I invite you to read up about its toxicity and lethality (user stories like: splashed a few ml on a leg, did all the emergency procedures exactly right, got quick emergency care, leg amputated, died anyways).
      - snuxoll 7y ago
        S04E20 of ER had a patient die due to contact exposure to hydrofluroic acid, I had to look it up after reading this comment to make sure I got it right - don’t know why but it’s one of the most memorable to me. Seriously, don’t mess around with this shit - even IF you notice exposure (hard, because you may not even notice until it’s too late) there’s a good chance it’s already a done deal.
        wnkrshm 7y ago
        I'm glad that I don't have to work with the stuff after reading up on emergency medical procedures. I once found a very long list of what to do by an expert MD and it's really not pretty. I'm not an expert in either chemistry or medicine but what I gathered was: The medical team needs to try and offset what the fluor is doing to the balance of ions in your body, to keep your cells alive. HF will diffuse within pretty much all of your tissues (including diffusing into bone like it was a sponge iirc) and a medical team will check your blood ion levels every five minutes or so while sticking you with CaCl (iirc) injections along the path the HF may diffuse through your body (if you're lucky enough to have hit an extremety like a hand). While the HF is diffusing, you will not feel anything. They cannot just pump you full of the proper ions to counteract the effects of the fluor and maybe bind it because that would kill you as well, they have to hit the right elevated concentration locally to offset what the fluor is doing. Edit: I've read up on it again and some of the things I wrote aren't right and I misremembered, like HF exposure being painless. At first it may be so but once the calcium levels drop, exposure is connected to extreme, "deep" pain. Treatment guides stress to not admister aneasthetics because the pain is the best indicator for successful treatment. Also, Calcium Gluconate is recommended, not Calcium Chloride. This [0] is a detailed source I found (PDF). [0] (PDF) https://ehs.unc.edu/files/2015/09/hfaexposure.pdf https://ehs.unc.edu/files/2015/09/hfaexposure.pdf
- Accujack 7y ago
  Sand blasting would work, although less well than on other glass types. Acid etching would work, although the chemicals needed are dangerous and it's apparently quite a finicky process to get a good result - over etching results in a less visible etched pattern than optimal exposure to the acid. To laser etch borosilicate you'd have to use an expensive laser, either an abnormally high powered IR laser or something higher frequency like a UV laser. It wouldn't be enough to just melt or heat stress bits off the surface, you'd have to micro structure (microscopic 3d carve) it to form something that would reflect light well, otherwise you wouldn't be able to see the etched pattern except in certain light. On top of that the depth of field issues for a laser apply as well as the incident angle for the beam - you'd want something close to a surface normal angle to get a consistent, controllable result, so you'd have to use a 5 axis machining setup to make sure that happens. A 5 axis precision UV laser would probably cost more to run than the bottles are worth, despite their quality. What I'd probably do if I had to label bottles like these with names is make a small soda glass plaque or tag with a mold and possibly some color tint for contrast, then etch it using an appropriate method (or maybe even mold the name in) and affix it to the bottle either by heating and slumping it into place or molding it to a matching curve and then using optical adhesive to affix it. Or, just make a nice display box for it and put the name on a brass plaque on the front :)
jcoder 7y ago
A lot of people are trying to solve for etching and engraving here, but if I wanted to personalize a glass piece that already (kind of, in some world) looks like it belongs in a lab, I think I’d try an enamel paint process instead. May have a nicer result than a label maker, depending on taste.

driverdan 7y ago

Did he say why laser engraving wouldn't work? I can see the curves causing some distortion but you should be able to compensate for that. Edit: He answers the question in his FAQ > The borosilicate glass laughs at laser beams ..which makes sense. Seems like sand blasting would be the best way.

CliffStoll 7y ago
In short - engraving borosilicate is difficult, because it does not expand very much when heated. So when hit by an infrared laser beam, the glass doesn't locally expand and spall off a tiny speck of glass .... instead, the glass locally melts. When the beam moves on to the next pixel, the first site either solidifies or sometimes dribbles away. Laser engraving of borosilicate just doesn't work well. And, because of the compound curves of the Klein bottle, you need a big depth of field as well as a rotary bottle holder. All laser engravers that I've played with have a very short (10mm or so) depth of field. Diamond engraving doesn't work well because of the curves. Sandblasting with a rubber mask works, but making the mask is a pain. So, after lots of attempts, I've given up on engraving these guys. Also: mistakes are expensive -- this is hand-blown glass.
- dlgeek 7y ago
  (Everyone should make sure to note the name on the above comment) Thanks for answering, and congratulations on your book's anniversary. My job gives out copies of your book as a somewhat prestigious award to those who find and report security problems, and I'm very happy to have both received and read a copy.
- numlocked 7y ago
  This is basically exactly what you told me on the phone :) We also had a fun digression about sand-blasting tombstones. And of course, we covered the hand-engraving/dremel option. So...label maker.
- pmoriarty 7y ago
  Can't acid be used to etch glass? Also, why not use glass that's easier to etch?
  - wnkrshm 7y ago
    With quartz glass, it's going to be hydrofluoric acid and I invite you to read up about its toxicity and lethality (user stories like: splashed a few ml on a leg, did all the emergency procedures exactly right, got quick emergency care, leg amputated, died anyways).
    - snuxoll 7y ago
      S04E20 of ER had a patient die due to contact exposure to hydrofluroic acid, I had to look it up after reading this comment to make sure I got it right - don’t know why but it’s one of the most memorable to me. Seriously, don’t mess around with this shit - even IF you notice exposure (hard, because you may not even notice until it’s too late) there’s a good chance it’s already a done deal.
      - wnkrshm 7y ago
        I'm glad that I don't have to work with the stuff after reading up on emergency medical procedures. I once found a very long list of what to do by an expert MD and it's really not pretty. I'm not an expert in either chemistry or medicine but what I gathered was: The medical team needs to try and offset what the fluor is doing to the balance of ions in your body, to keep your cells alive. HF will diffuse within pretty much all of your tissues (including diffusing into bone like it was a sponge iirc) and a medical team will check your blood ion levels every five minutes or so while sticking you with CaCl (iirc) injections along the path the HF may diffuse through your body (if you're lucky enough to have hit an extremety like a hand). While the HF is diffusing, you will not feel anything. They cannot just pump you full of the proper ions to counteract the effects of the fluor and maybe bind it because that would kill you as well, they have to hit the right elevated concentration locally to offset what the fluor is doing. Edit: I've read up on it again and some of the things I wrote aren't right and I misremembered, like HF exposure being painless. At first it may be so but once the calcium levels drop, exposure is connected to extreme, "deep" pain. Treatment guides stress to not admister aneasthetics because the pain is the best indicator for successful treatment. Also, Calcium Gluconate is recommended, not Calcium Chloride. This [0] is a detailed source I found (PDF). [0] (PDF) https://ehs.unc.edu/files/2015/09/hfaexposure.pdf https://ehs.unc.edu/files/2015/09/hfaexposure.pdf
Accujack 7y ago
Sand blasting would work, although less well than on other glass types. Acid etching would work, although the chemicals needed are dangerous and it's apparently quite a finicky process to get a good result - over etching results in a less visible etched pattern than optimal exposure to the acid. To laser etch borosilicate you'd have to use an expensive laser, either an abnormally high powered IR laser or something higher frequency like a UV laser. It wouldn't be enough to just melt or heat stress bits off the surface, you'd have to micro structure (microscopic 3d carve) it to form something that would reflect light well, otherwise you wouldn't be able to see the etched pattern except in certain light. On top of that the depth of field issues for a laser apply as well as the incident angle for the beam - you'd want something close to a surface normal angle to get a consistent, controllable result, so you'd have to use a 5 axis machining setup to make sure that happens. A 5 axis precision UV laser would probably cost more to run than the bottles are worth, despite their quality. What I'd probably do if I had to label bottles like these with names is make a small soda glass plaque or tag with a mold and possibly some color tint for contrast, then etch it using an appropriate method (or maybe even mold the name in) and affix it to the bottle either by heating and slumping it into place or molding it to a matching curve and then using optical adhesive to affix it. Or, just make a nice display box for it and put the name on a brass plaque on the front :)

jcoder 7y ago

A lot of people are trying to solve for etching and engraving here, but if I wanted to personalize a glass piece that already (kind of, in some world) looks like it belongs in a lab, I think I’d try an enamel paint process instead. May have a nicer result than a label maker, depending on taste.