Day: May 10, 2022

Large Scale Carbon Capture Without The Technology

May 10, 2022 by 213 Comments

We humans are in something of a pickle, as we’ve put too much carbon dioxide in the atmosphere and caused climate change that might even wipe us out. There may still be people to whom that’s a controversial statement, but knowing something needs to be done about it should be a position for which you don’t necessarily have to be a climate change activist glueing yourself to the gates of a refinery.

It’s obvious that we can reduce our CO2 emissions to tackle the problem, but that’s not the only way that atmospheric CO2 can be reduced. How about removing it from the air? It’s an approach that’s being taken seriously enough for a number of industrial carbon capture solutions to be proposed, and even for a pilot plant to be constructed in Iceland. The most promising idea is that CO2 from power stations can be injected into porous basalt rock where it can react to form calcium carbonate. All of which is very impressive, but is there not a way that this can be achieved without resorting to too much technology? Time for Hackaday to pull out the back-of-envelope calculator, and take a look. Continue reading “Large Scale Carbon Capture Without The Technology” →

3D Print Finishing By Spraying Glazing Putty

May 10, 2022 by 19 Comments

Finishing off 3D prints is a labour-intensive process, and getting a good looking, smooth surface suitable for painting takes a lot of time and plenty of practice. Deeper printing layer lines or minor surface defects can be smoother over with a variety of materials, from putties to resins, but the deeper the defect, the thicker the filler and that takes it toll on the surface details – smoothing those out and making fine details less distinct. [Darkwing dad] has another solution that looks pretty easy to achieve, by mixing acetone with glazing putty it can be airbrushed over the print surface in one go. After a little experimentation with the ratio of putty to acetone, a wide open nozzle and a low pressure, it was found that a nice even spray could be achieved. Importantly it dries in just a few minutes, enabling multiple coats to be applied in a short space of time.

Once sufficient thickness has been applied, the coating can easily sanded to get a smooth result with the worst of the gaps filled, and the layer lines nicely hidden. The final part of the filling process is more typical, with a few coats of filler primer applied straight from a rattle can, followed by a light sand and you’re good for painting.

We’ve covered smoothing 3D prints practically as long as we’ve been covering 3D printing itself, and there are multiple ways to do this, depending on the filament material, your budget and you tolerance for noxious fumes. Here’s a guide for smoothing using UV curable resins, using a special smoothable filament with IPA, and finally if this is just too fancy, smelly or expensive, just whip out the old butane torch and smooth those prints with good old fashioned fire.

Continue reading “3D Print Finishing By Spraying Glazing Putty” →

Becky Stern, David Cranor, And A CT Scanner Vs The Oura Ring

May 10, 2022 by 7 Comments

If you wonder how it’s possible to fit a fitness tracker into a ring, well, you’re not alone. [Becky Stern] sent one off to get CT scanned, went at it with a rotary tool, and then she made a video about it with [David Cranor]. (Video embedded below.)

While it’s super cool that you can do a teardown without tearing anything down these days — thanks to the CT scan — most of the analysis is done on a cut-up version of the thing through a normal stereo microscope. Still, the ability to then flip over to a 3D CT scan of the thing is nice.

We absolutely concur with [Becky] and [David] that it’s astounding how much was fit into very little space. Somewhere along the way, [David] muses that the electrical, mechanical, and software design teams must have all worked tightly together on this project to pull it off, and it shows. All along, there’s a nice running dialog on how you know what you’re looking at when tearing at a new device, and it’s nice to look over their shoulders.

Then there’s the bit where [Becky] shows you what a lithium-ion battery pack looks like when you cut it in half. She says it was already mostly discharged, and she didn’t burst into flames. But take it easy out there! (Also, make sure you take your hot xylene out on the patio.)

X-ray machines are of course just the coolest thing when doing a teardown. We’ve seen them used from fixing multimeters to simply looking at servo motors.

Continue reading “Becky Stern, David Cranor, And A CT Scanner Vs The Oura Ring” →