elDalvini

I think this might just be a particularly uncooperative tire, but it should work if you wrestle it on there. Maybe post a picture of the whole wheel, there might be something here I'm missing.

Alt text:

The zoo takes special care to keep kings separated from opposite-color pieces as part of their conservation program to prevent mating in captivity.

Unpopular opinion: The license makes sense and should have been enforced from the start.

The Benchy is a benchmarking tool, not just visually but there are also various features you can measure and check against the dimensions on the website. But that doesn't work if the model you're printing has been modified.

If it looks like a beachy, it should have been printed from the original model, so it's always comparable. Preventing derivatives means you can be sure of that, even if it came on the included SD card with your printer. Otherwise, manufacturers could include a modified model that makes their printers look better than they are.

Relevant xkcd

Every single freewheel does this, and it's not an issue.

The freewheel bearings don't line up exactly with the wheel bearings. This is always the case to some degree, because the interface between freewheel and hub is a non-precision thread.

It might look weird when freewheeling, but once you put use the pedals, freewheel and hub are rotating together, negating this wobble.

If you can wait a couple weeks, AliExpress is going to be the cheapest.

eBay may be a bit more expensive, but it's often my go-to because you can find everything and usually there are options with short shipping times.

For not too obscure parts, I would look at Reichelt, their prices are surprisingly low (especially if you bundle your orders to save on shipping costs).

Can you get a big flathead screwdriver in there to carefully knock it out? It should allow you to get a better angle than the dedicated tool.

Go slowly and alternate the places you're putting the end of the screw driver. You want to push the cup out evenly, or it will jam and possibly deform the head tube.

HiPER Calc Pro. A great scientific calculator I use constantly. (There is also a unpaid, ad-supported version, and the ads weren't too intrusive the last time I tried it)

That's probably not a bad idea, although I doubt it will make much of a difference. But since you're redesigning the whole thing, might as well do it.

It looks like you would want an even airflow through the whole PSU. The main heat-generating components are using the sides of the housing as a heat sink. I'm guessing the fan is mostly so the air inside the housing doesn't get too warm, not to cool individual components.

Where is the original air exhaust? If it's near the bottom of the picture, that would confirm my theory. In that case, I would keep the fan placement as close to original as possible (i.e. the blue square).

You can use a boost converter to boost the 5V of an USB port to the 19V your notebook needs.

Assuming 5A output from a powerbank (which is probably about the max you will get without USB PD), you could theoretically get 0.55A at 19V. With the unavoidable inefficiencies, you will get less.

So, maybe enough to very slowly charge your notebook while it's off. But when it's turned on, the battery charge will still drop.

Sure, the skull is biodegradable. But didn't you know that large-scale human farming is responsible for the vast majority of CO2 emissions?!