How To Make Conductive Tin Oxide Coatings On Glass

October 11, 2024 by Lewin Day 19 Comments

Glass! It’s, uh, not very conductive. And sometimes we like that! But other times, we want glass to be conductive. In that case, you might want to give the glass a very fine coating of tin oxide. [Vik Olliver] has been working on just that, in hopes he can make a conductive spot on a glass printing bed in order to use it with a conductive probe.

[Vik’s] first attempt involved using tin chloride, produced by dissolving some tin in a beaker of hydrochloric acid. A droplet of this fluid was then dropped on a glass slide that was heated with a blowtorch. The result was a big ugly white splotch. Not at all tidy, but it did create a conductive layer on the glass. Just a thick, messy one. Further attempts refined the methodology, and [Vik] was eventually able to coat a 1″ square with a reasonably clear coating that measured an edge-to-edge resistance around 8 megaohms.

If you’re aware of better, easier, ways to put a conductive coating on glass, share them below! We’ve seen similar DIY attempts at this before, too. If you’ve been cooking up your own interesting home chemistry experiments (safely!?) do let us know!

The Strangest Way To Stick PLA To Glass? With A Laser And A Bit Of Foil

September 2, 2024 by Donald Papp 7 Comments

Ever needed a strong yet adhesive-free way to really stick PLA to glass? Neither have we, but nevertheless there’s a way to use aluminum foil and an IR fiber laser to get a solid bond with a little laser welding between the dissimilar materials.

A piece of sacrificial aluminum foil bonds the PLA to glass with a form of laser welding, with precise control and very little heat to dissipate.

It turns out that aluminum can be joined to glass by using a pulsed laser process, and PLA can be joined to aluminum with a continuous wave laser process. Researchers put them together, and managed to reliably do both at once with a single industrial laser.

By putting a sacrificial sheet of thin aluminum foil between 3D printed PLA and glass, then sending the laser through the glass into the aluminum, researchers were able to bond it all together in an adhesive-free manner with precise control, and very little heat to dissipate. No surface treatment of any kind required. The bond is at least as strong as any adhesive-based solution, so there’s no compromising on strength.

When it comes to fabrication, having to apply and manage adhesives is one of the least-preferable options for sticking two things together, so there’s value in the idea of something like this.

Still, it’s certainly a niche application and we’ll likely stick to good old superglue, but we honestly didn’t know laser welding could bond aluminum to glass or to PLA, let along both at once like this.

UC Berkeley Prints Glass Nanoparticles

August 15, 2024 by Al Williams 8 Comments

In a recent video, [Joel] of 3D Printing Nerd interviews a researcher at University of California, Berkeley about their work with glass 3D printing technology. A resin is impregnated with tiny glass nanoparticles and produces green parts. An oven burns away the resin and then another heating step produces the actual silica glass part. You can see a video about the process below.

As you might expect with glass, the temperatures are toasty. The first burn is at 1100 C and the fusing burn is at 1300 C. The nanoparticles are about 40 nanometers across. The resulting parts are tiny with very small feature sizes. The technology to do this has been around for a few years, and the University continues researching this form of computed axial lithograph (CAL) 3D printing. These parts are so small that it uses an adaptation called microCAL that produces much smaller parts at high precision. However, the equipment available today won’t produce very large objects. The video talks about the uses for some of these small glass items.

We wonder how much the firings in the ovens change the tiny tolerances. They obviously work, so either they account for that or it doesn’t shrink much.

If you want your own 3D printed glass, a laser system might be more practical. If you just want transparent plastic, your FDM printer can do that. Really.

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Supremely-tough Glass Performs Under Pressure

August 24, 2023 by Donald Papp 25 Comments

There’s some nifty research from the University of Bayreuth, together with partners in China and the U.S., on creating supremely tough aluminosilicate glass that boasts an unusual structure. The image above represents regular glass structure on the left, and the paracrystalline structure on the right.

Aluminosilicate, which contains silicon, aluminum, boron and oxygen, is a type of oxide glass. Oxide glasses are a group to which borosilicate and other common glasses belong. Structurally speaking, these glasses all have a relatively disordered internal structure. They’re known for their clarity, but not especially their durability. Continue reading “Supremely-tough Glass Performs Under Pressure” →

Retrotechtacular: Circuit Potting, And PCBs The Hard Way

June 15, 2023 by Dan Maloney 8 Comments

There was a time when the very idea of building a complex circuit with the intention of destroying it would have been anathema to any electrical engineer. The work put into designing a circuit, procuring the components, and assembling it, generally with point-to-point wiring and an extravagant amount of manual labor, only to blow it up? Heresy!

But, such are the demands of national defense, and as weapons morphed into “weapon systems” after World War II, the need arose for electronics that were not only cheap enough to blow up but also tough enough to survive the often rough ride before the final bang. The short film below, simply titled “Potted and Printed Circuits“, details the state of the art in miniaturization and modularization of electronics, circa 1952. It was produced by the Telecommunications Research Establishment (TRE), the main electronics R&D entity in the UK during the war which was responsible for inventions such as radar, radio navigation, and jamming technology.

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Nuke Your Own Uranium Glass Castings In The Microwave

April 26, 2023 by Dan Maloney 20 Comments

Fair warning: if you’re going to try to mold uranium glass in a microwave kiln, you might want to not later use the oven for preparing food. Just a thought.

Granted, uranium glass isn’t as dangerous as it might sound. Especially considering its creepy green glow, which almost seems to be somehow self-powered. The uranium glass used by [gigabecquerel] for this project is only about 1% U₃O₈, and isn’t really that radioactive. But radioactive or not, melting glass inside a microwave can be problematic, and appropriate precautions should be taken. This would include making the raw material for the project, called frit, which was accomplished by smacking a few bits of uranium glass with a hammer. We’d recommend a respirator and some good ventilation for this step.

The powdered uranium glass then goes into a graphite-coated plaster mold, which was made from a silicone mold, which in turn came from a 3D print. The charged mold then goes into a microwave kiln, which is essentially an insulating chamber that contains a silicon carbide crucible inside a standard microwave oven. Although it seems like [gigabecquerel] used a commercially available kiln, we recently saw a DIY metal-melting microwave forge that would probably do the trick.

The actual casting process is pretty simple — it’s really just ten minutes in the microwave on high until the frit gets hot enough to liquefy and flow into the mold. The results were pretty good; the glass medallion picked up the detail in the mold, but also the crack that developed in the plaster. [gigabecquerel] thinks that a mold milled from solid graphite would work better, but he doesn’t have the facilities for that. If anyone tries this out, we’d love to hear about it.

Making Neon Trees The Easy Way With No Oven Pumps Required

April 20, 2023 by Lewin Day 26 Comments

Neon lamps are fun and beautiful things. Hackers do love anything that glows, after all. But producing them can be difficult, requiring specialized equipment like ovens and bombarders to fill them up with plasma. However, [kcakarevska] has found a way to make neon lamps while bypassing these difficulties.

[kcakarevska] used the technique to great effect on some neon tree sculptures.

The trick is using magnesium ribbon, which is readily available form a variety of suppliers. The ribbon is cut into small inch-long fragments and pushed into a borosilicate tube of a neon sculpture near the electrode. Vacuum is then pulled on the tube down to approximately 5 microns of pressure. The tube is then closed off and the electrode is heated using an automotive-type induction heater. In due time, this vaporizes the magnesium which then creates a reactive getter coating on the inside of the tube. This picks up any oxygen, water vapor, or other contaminants that may have been left inside the tube without the need for an oven vacuum pumping stage. The tube is then ready to be filled with neon. After about 24 to 48 hours of running, the getter coating will have picked up the contaminants and the tube will glow well.

It’s a useful technique, particularly for complex neon sculptures that won’t readily fit in an oven for pumpdown. If the glasswork is still too daunting, though, you can always use other techniques to get a similar look. Video after the break.

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