There’s a wild new feature making repair jobs easier (not to mention less messy) and iFixit covers it in their roundup of the iPhone 16’s repairability: electrically-released adhesive.

Here’s how it works. The adhesive looks like a curved strip with what appears to be a thin film of aluminum embedded into it. It’s applied much like any other adhesive strip: peel away the film, and press it between whatever two things it needs to stick. But to release it, that’s where the magic happens. One applies a voltage (a 9 V battery will do the job) between the aluminum frame of the phone and a special tab on the battery. In about a minute the battery will come away with no force, and residue-free.

There is one catch: make sure the polarity is correct! The adhesive releases because applying voltage oxidizes aluminum a small amount, causing Al3+ to migrate into the adhesive and debond it. One wants the adhesive debonded from the phone’s frame (negative) and left on the battery. Flipping the polarity will debond the adhesive the wrong way around, leaving the adhesive on the phone instead.

Some months ago we shared that Apple was likely going to go in this direction but it’s great to see some hands-on and see it in action. This adhesive does seem to match electrical debonding offered by a company called Tesa, and there’s a research paper describing it.

A video embedded below goes through the iPhone 16’s repairability innovations, but if you’d like to skip straight to the nifty new battery adhesive, that starts at the 2:36 mark.

My sister is a beekeeper, or maybe a meta-beekeper. She ends up making more money by breeding and selling new queen bees to other beekeepers than she does by selling honey, but that doesn’t mean that she doesn’t also process the sweet stuff from time to time. She got a free steam-heated oscillating hot knife, used for cutting the waxy caps off of the tops of the cells before spinning the combs down to extract honey, and she thought it might be easier to use than her trusty hand-held electric hot knife.

The oscillating knife, which was built something like a century ago, hadn’t been used in decades. All of the grease had turned to glue, and the large v-belt wheel that made it go was hard to turn by hand, and the motor was missing anyway. So she gave it to my father and me as a project. How could we resist?

We found the original manual on the Internet, which said that it would run from any 1/2 hp motor, or could be optionally driven by a takeoff wheel from a tractor – unfortunately not an option in my sister’s honey house. But we did find a 3/4 hp bench grinder at Harbor Freight that conveniently fit inside the case, and bought the smallest v-belt pulley wheel that would fit the grinder’s arbor. We thought we were geniuses, but when we hooked it all up, it just stalled.

We spent more than a few hours taking the mechanism apart. It was basically an eccentric shaft with a bearing on the end, and the bearing ran back and forth in the groove of a sliding mechanism that the knife blade attached to. As mentioned above, everything was gunked, so we took it all apart. The bearing was seized, so we freed that up by getting the sand out of the balls. The bearing couldn’t move freely in the slide either, but we filed that down until it just moved freely without noticeable play. We added grease from this century, and reassembled it. It turned fine by hand.

But with the belt and motor attached, the mechanism still had just enough friction to stall out the motor. Of course we wrapped some rope around the shaft and pull-started it, and it made a hell of a racket, nearly vibrated itself off the table, and we could see that the marvelous zinc-coated frame that held it all together was racking under the tension. It would require a wholly new housing to be viable, and we hadn’t even figured out a source of steam to heat the knife.

In short, it was more trouble than it was worth. So we packed up the bench grinder in the original container, and returned it no-worse-for-wear to the Freight. But frankly, we had a fantastic time playing around with a noble machine from a long-gone past. We got it “working” even if that state was unworkable, and we were only out the cost of the small v-belt pulley. Who says all of your projects have to be a success to be fun?

In today’s value-engineered world, getting a decade of service out of a cordless tool is pretty impressive. By that point you’ve probably gotten your original investment back, and if the tool gives up the ghost, well, that’s what the e-waste bin is for. Not everyone likes to give up so easily, though, which results in clever repairs like the one that brought this cordless driver back to life.

The Black & Decker “Gyrodriver,” an interesting tool that is controlled with a twist of the wrist rather than the push of a button, worked well for [Petteri Aimonen] right up until the main planetary gear train started slipping thanks to stripped teeth on the plastic ring gear. Careful measurements of one of the planetary gears to determine parameters like the pitch and pressure angle of the teeth, along with the tooth count on both the planet gear and the stripped ring.

Here, most of us would have just 3D printed a replacement ring gear, but [Petteri] went a different way. He mentally rolled the ring gear out, envisioning it as a rack gear. To fabricate it, he simply ran a 60° V-bit across a sheet of steel plate, creating 56 parallel grooves with the correct pitch. Wrapping the grooved sheet around a round form created the ring gear while simultaneously closing the angle between teeth enough to match the measured 55° tooth angle in the original. [Petteri] says he soldered the two ends together to form the ring; it looks more like a weld in the photos, but whatever it was, the driver worked well after the old plastic teeth were milled out and the new ring gear was glued in place.

We think this is a really clever way to make gears, which seems like it would work well for both internal and external teeth. There are other ways to do it, of course, but this is one tip we’ll file away for a rainy day.