Thanks for the reminder about Gemini… I decided to try it out and have been enjoying the process so far. We’ll see how it goes!

Definitely neat, particularly in some sort of disaster scenario where you’re building stuff out of scrap. I bet you could replace those aluminum “offset printing plates” with sheet aluminum from cars that are built with it. (Mostly fairly pricey ones, but I’m thinking of scenarios where that’s no longer an issue.)

In more prosaic situations though, modern PV panels can produce more wattage even in marginal latitudes. So I’d think of wind turbines as something to supplement a system and maybe lighten the load on batteries during overnight hours, rather than a primary power source.

In the marine world, small 12V wind turbines used to be a pretty common sight on the back of sailboats… which is really about the best possible situation for one. (Sailboats tend to be located in places that have brisk winds.) But in the last 10 years most people have stopped bothering to install them, and are making more and more flat surfaces out of PV panels instead. You just get more bang for the buck buying more PV panels and batteries than you do buying a wind turbine setup.

But for scenarios where it makes sense, I love seeing designs that don’t assume you have the entire McMaster-Carr catalog at your disposal.

Looks great! I’ve looked at that box design and wasn’t sure about the “grip rails” that it has on the lid, or the rails on the box; they seem kinda fragile-looking to me, at least made out of wood. How did you improve the lid design? And does it feel solid when made out of acrylic?

I have not engraved rock on my current laser, but several years back at TechShop (still bitter they are gone) I did some slate tiles and they came out well. I don’t know where they were sourced from because I found them lying around.

I didn’t change the laser lens or do anything out of the ordinary for it. I think they had a little stick that was cut to the laser’s focal distance, and I used that to focus it right on the surface of the stone.

It left a slightly rough, matte white surface where I had engraved. This was probably at maybe 30-50W with air assist on?

Not sure what results you would get from other kinds of rock, e.g. granite. My gut says you’d want to avoid rock with lots of reflective crystals in it, e.g. quartz or silica-bearing rock, but I don’t have any solid evidence for that.