A self-made documentary on how quartz glass can be manipulated in a glassblowing workshop. Here I am making a product called Cetane Flasks. Hope you find it interesting!
Such a wonderful skill. I believe the white bloom is condensed silicon monoxide, the working temperature being so high that the silica vaporises, partially dissociates and condenses onto the comparatively cooler parts. A gentle reheat, as you say, restores it to the dioxide, which then dissolves back into the bulk. Many thanks for such a great video.
Thought i'd add this. "Pyrex glass transmits most of the incident light above about 300 nm and may be used in the construction of apparatus for reactions which require light above this wavelength. Quartz vessels, transparent down to 200 nm, must be used for reactions which require light below 300 nm. Certain types of quartz allow transmission below 200 nm." *Vogel's Textbook of Practical Organic Chemistry (5th Edition)* It's free on library genesis FYI.
I used to work a lot of quartz in the 70's for the semiconductor industry. the bloom is best avoided by preheating the a couple of inchs up. We also used hydroflouric acid to etch it away. Never got UV burns, eyes are still fine 40 plus years. Interesting using hydrogen oxygen for heat, but never really liked working quartz vs borosilicate, yet you do what you are paid to.
What’s was it like back In the 70’s working scientific? Where people open with knowledge or did everyone keep to them self and not share information and techniques?
Greetings from Brazil, Natalie. Thank you very much for the opportunity to see your Wonderfull Work with the Scientific Glassblowing!!! GREAT!!! PARABÉNS!!! 👏👏👏👏👏👏👏👏👏👏 🌷🌷🌷🌷🌷🌷🌷🌷🌷🌷
Great vid, with some great looking results! That white flare-off from fused quartz looks so intense. I bet a lot of UV light is generated, hence the "sunburn". Good on you for taking PPE seriously. I've been working with pretty scary chemicals for 25+ years, and always admire folks that are smart and take time to wear protective equipment. Keep the great vids coming!
Great job! I'm a chemistry newbie and really enjoy the glassware vids. Interesting stuff, plus your vids are well made...they're not tedious to watch, or posted with bad audio, etc.
Where did you learn your trade? I'm seriously contemplating going to Salem CC to take the program there, but I don't know if it would be better to try to apprentice with someone.
Suuuuuuper high heat reactions. The strain point of quartz is 1120C, so you could safely use this in reactions up to at least 925C as many times as you want without worry of failure. Borosilicate strain point is only 515C for comparison. My educated guess on the long neck is for the purpose of keeping that insane heat away from the rest of the apparatus. Glass is insulating, so it would take a long time for the heat to travel up the neck and apparatus. This is a very purpose built item, so I can't speak to a specific reaction. I mean the flask is on a very tiny scale and that looks like a 10mm joint, which is also super tiny. I'd venture a strong guess toward research or analytics rather than production.
It is for Ketene synthesis. She stated the use in the name (although I am not used to the spelling, but that might just be a region thing) the legend Doug's Lab made 2 videos about a similar process these would typically be used for. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-_1mMW2qEF84.html
Hello Natalie, Can borosilicate be welded to quartz? I need to weld a halogen lamp to a glass tube and borosilicate tube would much easier! Its for vacuum work and I need to test myself the idea first
While I'm not Natalie I'll drop my twopence here anyway ;-) Generally speaking, the biggest obstacle to joining two different types of glass is the difference in their respective thermal coefficients. Too big, and try as you may, the joint will always crack. Quartz glass has an extremely low thermal coefficient, so low that it won't crack even if you put it, red hot, straight into water. Uncle Google says: _"Borosilicate glasses are known for having very low coefficients of thermal expansion (∼5 × 10^−6/ °C at 20 °C)"_ - low FOR A GLASS, that is - which is still pretty high "generally speaking". _"One of the most attractive features of quartz glass is its very low thermal coefficient of expansion (CTE). The average CTE value for quartz glass at about 5.0 × 10^ -7/ °C is many times lower than that of other common materials"_ So it looks like the CET of borosilicate glass is TEN TIMES higher than that of quartz glass, thus "I doubt it very much". Then there's a huge difference in melting (softening) temperature: 820°C vs 1670°C, so when you touch softened borosilicate element to softened quartz glass, the former will probably just melt completely and drip down as a rather runny liquid.
excellent work, quartz is a stone! hahaha first time i see they make them. At what temperature in the oven do the spots that form around the weld disappear? sorry if i wrote you wrong
Thank you. Yeah it's a b****rd to work with! We don't actually have an oven that can handle annealing quartz, so I warm it through by hand as we go. It's annoying when those white patches appear, but I just heat the glass til it's glowing but not yet soft, and that gets rid of them alright xx
@@Celebnariel bird? bitch? :D Yeah, I can imagine working with quarts to be hard, I didn't even know it can be hand blown, like you do it in the video. Hard work. Take care of protecting your skin and eyes, even on small jobs.
A colleague of mine working in a glass cell making is experiencing "fogging" after he welded a rectangle quartz cell. It looks like white stuff deposited on the glass surface. He claims it's vaporized SiO2 deposits. Have you experienced that? If so, what do you do to remove the deposits?
Some other viewer, MrEurypterid, commented on this "fogging": _"I believe the white bloom is condensed silicon monoxide, the working temperature being so high that the silica vaporises, partially dissociates and condenses onto the comparatively cooler parts. A gentle reheat, as you say, restores it to the dioxide, which then dissolves back into the bulk."_