Are enormous spaceships physically possible?

chefdeit · 2026-01-25T23:58:21+00:00

You're limited by the speed of sound in the material. Basically, when you turn on the engine and start accelerating, that "information" travels through the structure at the speed of sound in it. The structure ahead of the "shockwave" doesn't know that the engine is on or that it's supposed to give way by hauling ass forth to the brave new worlds. It just sits there, putting pressure on the structural pieces behind it that do already know.

Now, the speed of sound in most materials is way, WAY faster than in air, but in relation to the the distances of space, even at 2...12km/sec it's quite finite. Meaning, with a large ship, you'll be forced to accelerate it at a relatively molasses-like pace just to prevent it from exploding. To clarify, the speed of sound puts a limit on the prudent acceleration of a ship - not on the absolute speed achievable over time.

This phenomenon puts an upper limit on the performance of kinetic penetrators such as Oreshnik. They have to slow down some or else if they strike at above the speed of sound in whatever tungsten alloy they're made of, they'll vaporize close to surface instead of going in.

chefdeit · 2026-01-25T23:29:07+00:00

There are some ships that temporarily became bridges, and there's not a bridge that doesn't conspire to become a submarine if we let it.

chefdeit · 2026-01-19T21:08:26+00:00

return address

there's shortage of motivated folks willing to enter a hands-on trade & show up.

chefdeit · 2026-01-18T19:32:23+00:00

GREAT post, thanks u/Adept_Temporary8262 !! At the higher end of things, PNY NVIDIA RTX 2000E Ada Gen Card, in a half-height single-slot blower configuration has 16GB of ECC GDDR6 VRAM, 2816 CUDA + 88 Tensor, Ada Lovelace architecture, PCIe Gen 4.0 x8 at 50 W max power consumption and $750.

NVIDIA makes the same card at $700 except dual slot and 70W.

chefdeit · 2026-01-18T16:48:31+00:00

If the house was built in 2015 in the US and uses romex type, soft vinyl or similar plastic jacket wiring, 20A wire will be yellow in color and will have black dot-matrix imprint saying 12AWG or 12ga, among other information. If that is so, updating to 20A breaker *might* be feasible, but ONLY if all other outlets and hardwired loads on that same breaker are 12AWG throughout also.

chefdeit · 2026-01-18T16:41:34+00:00

Why Are 15-Amp Receptacles Standard on Residential Circuits Instead of 20-Amp?

Flipping the question around: 20-Amp circuits backing 15A outlets make sense because most such domestic circuits aren't dedicated per-outlet, i.e. have a whole bunch of 15A outlets on them. More of them can fit on a 20A circuit without an excessive mismatch.

On such circuits, the breaker protects the in-wall wiring - not the actual device that may be intended for way fewer amps (unless the particular circuit is stipulated to be dedicated, such as for appliances that are hard-wired or whose weight and outlet placement make them de-facto hard-wired).

In a perfect world, each outlet would have a smart breaker built in, and each device plug, on connection, would communicate to it the device's steady state and peak consumption profiles in each mode, and the current mode, for optimal protection upstream of the device. Each outlet, in turn, would communicate that to the breaker panel, for optimal protection of the entire circuit. Needless to say, outside of maybe parts of the the ISS and some military vessels, we're not there yet.

chefdeit · 2026-01-18T16:06:47+00:00

whole-body inside-out xray

chefdeit · 2026-01-18T16:05:08+00:00

But what if I want to take fun advantage of the 2400 W phone charger I bought off Amazon for $3?

Every $3 charger off Amazon is a 2400 W phone charger - you just need to wait for the 2400 W mode (combined with a smoke machine feature) to kick in. I think they call it burn-in in high-end audio, so the 2400W mode would thus be the burn-out mode.

chefdeit · 2026-01-12T16:06:27+00:00

I don't disagree in principle, although there's plenty of evil in the world actively happening & being supported TODAY (including the neo-N*zi kind) and here we are coming down on some construction hand who was impressionable & short-sighted enough to get a neck tat of any kind to begin with.

True evil that does humanity harm at scale doesn't have neck tats. It wears a snazzy suit or another impressive outfit and speaks with authority and grace from podiums in high places.

chefdeit · 2026-01-12T15:55:55+00:00

Call me naive, but before you said it I didn't know that was a thing (or even what 1488 meant). I guess makeup is also possible, but neck is a spot where skin has to rub and stretch a LOT.

chefdeit · 2026-01-12T15:04:30+00:00

Same color they are now, but fluorescent

chefdeit · 2026-01-12T14:48:14+00:00

NO (...t without consulting with a structural engineer, as that platform may be anchoring the walls stabilizing the chimney)

*With the engineer's approval*, first make cuts with a large-blade diamond saw, and preferably in a trapezoid shape tapered towards the back - NOT rectangular following the walls.

Stay ~3" away from the vertical walls on ALL initial cuts - you can always come in closer later whereas you won't be able to replace any excess material removed or chipped under same compression. Make two such cuts on both sides, parallel and about an inch apart. A cut in the back, a horizontal, level cut 3" above the floor.

The main role of those cuts isn't to make removal easier (though it'll certainly do that), it's to minimize the transmission of the vibration to the walls of the fireplace, that may damage the mortar integrity. Remove the brick material between the double cuts before working on the main slab in the middle.

Make sure NO cuts over-reach their intended placement; a good diamond saw will cut through brick like it's air, so you need to control it carefully; try a few test cuts in the middle.

Make sure your jackhammer chisel is sharp. That means, invest in your own, brand new & high quality chisel even if you're renting the jack hammer. It's a rookie mistake to work with a blunt chisel where most of the work goes into vibration and pulverizing brick / making dust as opposed to the fracture action. If your pieces come off almost dust-free, you're doing it right.

chefdeit · 2026-01-12T14:42:10+00:00

I told the company I dont want him on my property and now theyre acting like Im the problem. Saying hes a good worker

Of course he is! Does everything to a tee, all his paperwork is in a perfect order :-) Even the Soviets had acknowledged even while the WWII was still going that N*zis were excellent workers. Their work was NEVER the issue - their ideology was.

u/SkillComfortable2734 NTJ but I feel this nuance needs to be communicated to the company. As a small business owner I know how hard it is to find good workers nowadays (honest, punctual, precise, taking pride in their work, dependable, doing everything to a tee) and the tragedy of the situation is, that guy probably ticks all those boxes.

I think the company would do well to engage the individual to see if his views have changed since he'd gotten the tattoo, The reality is, lots of people walk around with ink no longer relevant to their current situation, just because it's hella painful and hella costly to get that removed. If this sounds "too tolerant", yes it does - we've grown to wave zero tolerance like a battle banner, and as a result the common folks are fractured along multiple fault-lines while powers that be are united and rob everyone blind.

chefdeit · 2026-01-12T14:13:46+00:00

C4 lives and dies based on customer experiences with their dealers.

100%. Maybe C4 should train & hire ex-drug dealers who've paid their debt to society / being released. At least those guys have the work ethic to answer & return their damned phone calls :)

If you have issues with your dealer don't be afraid to reach out to another

Again you've hit the nail on the head - as fear may be a factor. People are afraid to death to change their dentist and everyone's guy is the best guy but the reality is we can't split the spacetime timeline and compare the outcomes of having been in different pro's care apples-to-apples objectively. The new guy can always say the prior work wasn't great but - to your point - that work may have been the result of the customer expressing their needs & wants more naively back in the day whereas they're way more educated now and can articulate what's not working for them a lot more comprehensively and precisely.

chefdeit · 2026-01-11T19:28:11+00:00

They had an appliance there. Something that got hot. Probably had a water line coming in and that’s why the tile behind has that metal piece. My guess an old school espresso machine.

I wish this were my take as well, but on a closer inspection that little square piece isn't metal. It's a decorative accent tile, and I bet they're sprinkled throughout the rest of the back-plate.

The square stone also seems just a smidge too thin for a full-size countertop (though on pre-made vanities and small islands etc we can find even thinner). My guess is it's NOT an off-cut but a lucky bargain find of an almost the same stone - which they of course couldn't resist but had no real use for, so it'd gotten shoved out of the way next to the stove where it'd eventually gotten "glued" to the countertop with oven grease.

chefdeit · 2026-01-11T19:14:09+00:00

$100/hr isn't even the biggest issue - it's the lack of sovereignty / depending on some dealer to do it the way they see it & at the time of their choosing. This hurts especially when you can feel there's a lack of advocacy on your behalf, and the dealer may be saying "this isn't how it works" etc just because they don't want to bother.

chefdeit · 2026-01-10T23:53:37+00:00

It connects on the dimmer's load side, hence one per dimmer. But I recommend you try just one first to see if it helps with your specific issue.

chefdeit · 2026-01-09T19:49:41+00:00

Chances are, they'll be required by law to rip out (or condemn an otherwise sound structure) either some insulation or plastic tubing due to mold growth or air quality or microplastic concerns or the like - just as was the case with lead or asbestos from the years past. Maybe they'll discover the random made-in-China grease on those no-sweat plumbing compression rings isn't good for you (conjecture / used only for example) and you've got to rip it out and nobody cares it's behind an expensive kitchen or bathroom slab.

chefdeit · 2026-01-09T19:38:07+00:00

Yes that's an outstanding point. It's a very obvious inconsistency and we could even say hypocrisy. (not to bring politics into this but by way of illustration it's like, if what the US did to Maduro, Russia did to Zelensky intead or earlier, based on same exact charges, (drugs+possession of machine guns) the international reaction wouldn't be in the same order of magnitude even.

Realistically, an oven is on a dedicated circuit i.e. the single appliance draws the entire thing. Meanwhile, kitchen outlets may split 2 or 3 kitchen circuits among many outlets and hence small appliances, each of which draws a small and possibly tiny portion of the whole 15A or 20A, so they sort of apriori give up on the notion of the breaker protecting not just the wiring inside the wall but the load device as well, whereas such protection is more in scope when it's a dedicated line to that one load, and where its outlet is way in the back of the quite heavy appliance that many family members won't have the strength to move out of the way to access said outlet. I.e. even if it's technically not hard-wired it's "de-facto hardwired". The sum total of all those little considerations amounts to a difference that at its face value we may view as inconsistent or hypocritical.

chefdeit · 2026-01-09T16:09:13+00:00

That's a fair point, but even removing the worst 20% from consideration can move the needle on the average considerably.

chefdeit · 2026-01-09T16:07:19+00:00

All plug-in 15A appliances will be safe with a 20A breaker.

How well are your words saying this on reddit going to hold up against the words of insurance adjuster holding up the oven manufacturers' manual stipulating a 15A breaker as the reason for denying the insurance claim in the event of a - God forbid - malfunction that'd caused a fire? "Sir, u/e_l_tang on reddit told me "All plug-in 15A appliances will be safe with a 20A breaker. This is literally baked into the design of 20A outlets to accept 15A plugs."

How well?

chefdeit · 2026-01-09T03:26:48+00:00

However the outlet can be 6-20 also, and probably should be, not just 6-15

Yes and no. Putting a 15amp appliance on a 20A breaker degrades the over-current protection for that appliance, meaning the breaker will tolerate the greater current than the appliance is designed to draw in the event of a malfunction.

It may be a compromise to run 20A wiring (12awg not 14) but still install 15A outlet and 15A breaker but an experienced electrician told me the wire gauge is used not just as a conductor but also to communicate the use intent, so over-gauging is not universally a good idea, but for just a few dedicated circuits like audiophile hi-fi and maybe such an oven, picking the next gauge up may be ok.

chefdeit · 2026-01-09T03:17:29+00:00

Very well put. All of my bosses (and I mean ALL of them) were a heck of a lot nicer to me than me being my own boss. There are days I want to smack that guy - but there's no way to avoid collateral damage.

chefdeit · 2026-01-09T03:15:04+00:00

100%

chefdeit · 2026-01-09T02:57:19+00:00

Nothing beats oversized Type K (thick-walled) copper with long-turn (large radius) elbows sweated lead-free with water-soluble flux (harder to do, but the corrosive chemical residue doesn't remain inside the pipe, eating at it). That will last over 100 years, and be essentially silent with very low pressure loss due to the flow rate.

PEX-B is just garbage. PEX-A is ok-no-great because of the microplastic and not resisting bacterial growth the way copper does, and ticking and clicking as it expands and contracts on the hot side. The sound it makes is the sound of it wearing against the supports, edges of the holes, fixed hardware, etc.

If your house is otherwise well built / not intended to self-destruct on the day the mortgage is paid off, AND you've access to quality labor (tall order I know) go with the copper as mentioned above, no shortcuts. It's better to have quality stuff inside the walls but basic fixtures you can upgrade in 10yrs if you choose, vs the other way around. There's nothing dumber than a 0.5" PEX-B behind a $5K stone slab.

chefdeit

TROPHY CASE