Your pet peeve, technical or otherwise.

[SiliconWizard]

Looks like YT thumbnails are getting bigger and bigger as time passes.
Soon there will be only one video per page.

[shapirus]

When I ask for 37PSI they look at me like I have two heads.  "Not family runabout.  Sport car.  Yeah?"

Lol yeah. That surprised look. I ask them to slightly overinflate and explain that I'll adjust the pressure myself later (which I actually do, because I want to have it consistent across all tires to within 1 PSI). That satisfies the mechanics and they ask no more questions.

[Analog Kid]

My car the state 35PSI all round.  However I have a tendency to push that up to 37PSI in summer as it's more fun.  The car is a lot more skittish and responsive like a go kart.  At 30psi its a "wayward ditch finder" and at 35PSI is just mellow.  Not once but several times I have come out of mechanics or tyre places and wondered why the car handled like sh1t.  The checked the tyre pressures and found them at 30PSI.  When I ask for 37PSI they look at me like I have two heads.  "Not family runabout.  Sport car.  Yeah?"

I'd been inflating my tires to 32 PSI. But my tire guy told me I should be going to 40, so that's what I'll be doing from now on.

[woody]

37 psi or 2.5 bar does not seem too outrageous? The Mini needs at least 2.6 front and 2.4 rear to make me smile when handling a roundabout. The Tesla needs 3.1 bar all round for maximum km/Wh. I've never experienced uneven tire wear due to these pressures.

[helius]

Nice information.
However, are you sure about this:

Yes altitude play a role too, if you fill up the tire on top of the mountain, when you go down in the valley the tire have lost pressure. Yes, even if no air escaped.

Surely it's the other way around? The mass of air inside the tire is the same, but the atmospheric pressure has increased (at lower altitude), which compresses the tire volume --> higher tire pressure

[Analog Kid]

Nice information.
However, are you sure about this:

Yes altitude play a role too, if you fill up the tire on top of the mountain, when you go down in the valley the tire have lost pressure. Yes, even if no air escaped.

Surely it's the other way around? The mass of air inside the tire is the same, but the atmospheric pressure has increased (at lower altitude), which compresses the tire volume --> higher tire pressure

No, I think the post you quoted is correct. I told my tire guy what you just wrote, that if I went down to a lower elevation my tire pressure would increase, but he said it's just the opposite.

It's a matter of differential pressure between inside and outside: if you go to a lower altitude then the external pressure is higher, which acts against the tire's internal pressure and lowers the tire pressure.

The Veritasium guy on YooToob showed this by bringing a bag of chips aboard a plane; when the plane got up to cruising altitude the bag popped from the increased internal pressure (lower external pressure).

[TimFox]

Nice information.
However, are you sure about this:

Yes altitude play a role too, if you fill up the tire on top of the mountain, when you go down in the valley the tire have lost pressure. Yes, even if no air escaped.

Surely it's the other way around? The mass of air inside the tire is the same, but the atmospheric pressure has increased (at lower altitude), which compresses the tire volume --> higher tire pressure

No, I think the post you quoted is correct. I told my tire guy what you just wrote, that if I went down to a lower elevation my tire pressure would increase, but he said it's just the opposite.

It's a matter of differential pressure between inside and outside: if you go to a lower altitude then the external pressure is higher, which acts against the tire's internal pressure and lowers the tire pressure.

The Veritasium guy on YooToob showed this by bringing a bag of chips aboard a plane; when the plane got up to cruising altitude the bag popped from the increased internal pressure (lower external pressure).

Yes:  that's why the relevant variable for balloons and inflated tires is "gauge pressure", difference from ambient pressure, measured in "psig".

[paulca]

One general trade off is "grip" for "responsiveness". 

Low pressure sloppy tyres can flex a lot which nurfs your handling and makes them feel wayward.  It's two sides of the same coin.  When you or the cars momentum put control force into the tyre, the tyre flexes while retaining it's grip.

The only time I would take pressures down for this would be the winter tyres and for proper snow.  However, this just doesn't happen anymore here and if/when it does, I'm not getting down my 30% driveway even with winter tyres in snow.  Not without bob-sleighing out the drive way through the neighbours car, fence and kitchen wall.

[Xena E]

Overinflated car tyres are a very good way of causing a cracked windshield.

[themadhippy]

The Veritasium guy on YooToob showed this by bringing a bag of chips aboard a plane; when the plane got up to cruising altitude the bag popped from the increased internal pressure (lower external pressure).

And if you dont like flying take a bag of crisps on the train to lhasa

[paulca]

In homebrew with low pressure CO2 and large volumes there are some pretty cool tricks you can do with two interconnected vessels when you equalise their pressure and put them into feedback.  Even the "total column" height pressure differential (PSI at the bottom vs. PSI at the top of the vessel) can get things flowing.  You can think about it the long way like a gas plumbing engineer or you can stand back and realise it's just a "closed loop siphon, big deal?"

A PSA I feel I need to make.  When handling even 2 or 3 bar pressures.  NEVER, EVER pressure test with GAS.  That is all.

[Xena E]

In homebrew with low pressure CO2 and large volumes there are some pretty cool tricks you can do with two interconnected vessels when you equalise their pressure and put them into feedback.  Even the "total column" height pressure differential (PSI at the bottom vs. PSI at the top of the vessel) can get things flowing.  You can think about it the long way like a gas plumbing engineer or you can stand back and realise it's just a "closed loop siphon, big deal?"

A PSA I feel I need to make.  When handling even 2 or 3 bar pressures.  NEVER, EVER pressure test with GAS.  That is all.

Nah, superheated liquid Gallium is best for this job.

That's an irresponsible chemistry joke BTW. But hydraulic testing is the safest option for pressure vessels kids.

 

[vk6zgo]

The Veritasium guy on YooToob showed this by bringing a bag of chips aboard a plane; when the plane got up to cruising altitude the bag popped from the increased internal pressure (lower external pressure).

And if you dont like flying take a bag of crisps on the train to lhasa

If I was on the train to lhasa, the bag probably wouldn't last long enough for that effect to manifest itself.

[Analog Kid]

The Veritasium guy on YooToob showed this by bringing a bag of chips aboard a plane; when the plane got up to cruising altitude the bag popped from the increased internal pressure (lower external pressure).

And if you dont like flying take a bag of crisps on the train to lhasa

If I was on the train to lhasa, the bag probably wouldn't last long enough for that effect to manifest itself.

You could always bring an extra bag of something you hate (like I used to hate Fritos; gawd I couldn't stand those things!) for testing, the rest for eating.

[paulca]

Using MS Office 365 in work now is frustrating.  Not just Office 365 and Windows 11.  It's everything these days.  Why is it that EVERYTHING is a click spot now?  Why can't I just click a bit of text to highlight it and track where I'm reading without it switching into an Edit view.  In word now the title bar of the window has got so many click spots on it I can't find where to drag the window.  Where do I click to "focus" the window without clicking something?  Everything is live!

[SteveThackery]

Using MS Office 365 in work now is frustrating.  Not just Office 365 and Windows 11.  It's everything these days.  Why is it that EVERYTHING is a click spot now?  Why can't I just click a bit of text to highlight it and track where I'm reading without it switching into an Edit view.  In word now the title bar of the window has got so many click spots on it I can't find where to drag the window.  Where do I click to "focus" the window without clicking something?  Everything is live!

I've noticed the same thing, and it seems to be a problem across all platforms that use windows (lower case 'w') in the UI: where do you click to drag the window? It used to be the title bar, but loads of apps don't have a title bar any more.

[paulca]

It's "mobile cancer".

"What do you mean right click?  I only have one finger"
"What do you mean hover? I either touch the screen or I don't?"
"What do you mean focus the text box... What does focus mean?  I have to press it with my finger so the keyboard comes up? Duh old man!"
"CTRL+C... wha?"
"F'what?  F.. three?  What's that?"

[Zucca]

It's a matter of differential pressure between inside and outside: if you go to a lower altitude then the external pressure is higher, which acts against the tire's internal pressure and lowers the tire pressure.

Yes the manometer/tire pressure gauge you use for the tire shows a differential pressure =Ptire-Pamb.

The Ptire variation by changing the altitude can be ignored since the tire has the auto weight as major force on it.
BTW try to measure the tire pressures before and after lifting up the car in the workshop and unload the tire... 

The sensor inside the tire measure the Ptire absolute since it has no idea what the Pamb is.
One of the reasons the number you get in the TPMS display does not match the tire pressure gauge. Normally the number that goes in the display is Ptire - 1atm (SW subtracts 1 atm) hoping for the best.

Some OEMs use the amb pressure sensor from the engine to provide a better compensation, but it means more complication for a marginal benefit... most of the time not worth the pain.

[metrologist]

I have 4 cars with this TPMS and all of them just show the low tire pressure light.

Oh and hey Mr. tire guy can you fix that? No? You don't have time to wait for me to fix it while you have the tire off either?

[negativ3]

Non-compressible fluid, water is least messy.

In homebrew with low pressure CO2 and large volumes there are some pretty cool tricks you can do with two interconnected vessels when you equalise their pressure and put them into feedback.  Even the "total column" height pressure differential (PSI at the bottom vs. PSI at the top of the vessel) can get things flowing.  You can think about it the long way like a gas plumbing engineer or you can stand back and realise it's just a "closed loop siphon, big deal?"

A PSA I feel I need to make.  When handling even 2 or 3 bar pressures.  NEVER, EVER pressure test with GAS.  That is all.

[grumpydoc]

It's "mobile cancer".

"What do you mean right click?  I only have one finger"
"What do you mean hover? I either touch the screen or I don't?"
"What do you mean focus the text box... What does focus mean?  I have to press it with my finger so the keyboard comes up? Duh old man!"
"CTRL+C... wha?"
"F'what?  F.. three?  What's that?"

Or "tablet cancer" where you are expected to be using either your finger, or maybe a stylus but not a mouse. The result is that developers seem to have forgotten what "tab to next field" means.

That said ISTR that modern capacitive screens can distinguish "hover" from "touch" and most styli can go pressure sensing to differentiate "light touch" form "firm press".

[paulca]

Non-compressible fluid, water is least messy.

In homebrew with low pressure CO2 and large volumes there are some pretty cool tricks you can do with two interconnected vessels when you equalise their pressure and put them into feedback.  Even the "total column" height pressure differential (PSI at the bottom vs. PSI at the top of the vessel) can get things flowing.  You can think about it the long way like a gas plumbing engineer or you can stand back and realise it's just a "closed loop siphon, big deal?"

A PSA I feel I need to make.  When handling even 2 or 3 bar pressures.  NEVER, EVER pressure test with GAS.  That is all.

Yea, water.  I watched a video on why you pressure test with water of what happens when it fails.  It's very undramatic, the steel welds pop, rip open and half a pint of water squirts out.

I pressure test mine when they are hydro-locked with sanitizing solution.  Part of the process is to hydro-lock the kegs to force all gas out of them, 100% sanitizer solution, then pump that out with CO2, leaving you with an O2-free keg for racking to.  I only pressure test to my system pressure of 45PSI even though the kegs are rated to 100PSI, but I don't have any real way to push 100PSI into them to check the PRV even.  Nor do I want to.  My worst case would be a near empty keg failing at 45PSI, which is unlikely to breach the fridge they are in, but it would blow the door open and make a mess.

[paulca]

Doctor practices in the UK.

Consider this yellow warning on "mine's"  "Patients Services" portal:

Please refrain from using special characters '&' and '<' when sending a message to your practice when requesting prescriptions as this prevents the practice from processing your request in a timely fashion.

The mind can only boggle as to what bug resulted in that.  Is someone badly converting the textbox to HTML and not escaping it maybe?  The whole portal looks like it was setup by a 17yo in his Mum's basement.

Does the "Repeat perscriptions" work?  Hell no.  "Practice unavailable" since Thursday.

Decided to phone them.  5 minutes of listening to their "shock absorber" and I'd forgotten what I called them for, but I did actually catch the:

"For the automated repeat medication service, please phone and press 1 between 1pm and 3pm, Monday to Thursday."

Why is hells names is an answering machine service only available for 2 hours, 4 days a week?  WTAF?

For appointments you have to phone at 8:30.  If you phone at 8:31 you will get, "You are number 49 in the queue".  They usually only have 30 or 40 call backs a day anyway.  So you might as well hang up.  Now it's also looks like a short slot for perscriptions and for test results, they are all little 1 or 2 hour windows.

The thing is... ALL of these little windows are in "Work hours".  All of them have a tendency to stretch such as, "The doctor will call you between 9:00 and 12:00, they will not leave a message and they will not call back."

The thing is... I have a job, just like they do.  If they need their office hours to be a certain way to handle volume, why do they think I DONT?  How do they expect people with a full time job to get medical services when they are only open for short windows where I all 90% likely to have meetings.  Early morning and afternoon!

I suppose, looking out at the bigger picture of the UK, it's only going to get worse as we transition into a 2nd or 3rd world country.  Soon there will be no NHS.

[woody]

Doctor practices in the UK.

Consider this yellow warning on "mine's"  "Patients Services" portal:

Please refrain from using special characters '&' and '<' when sending a message to your practice when requesting prescriptions as this prevents the practice from processing your request in a timely fashion.

The mind can only boggle as to what bug resulted in that.  Is someone badly converting the textbox to HTML and not escaping it maybe?  The whole portal looks like it was setup by a 17yo in his Mum's basement.

Reminds me of my banking app; there you are not allowed a € sign in the message you can add to a transfer. These messages handle always about money, but don't you dare to use a €, £ or $ sign.

[paulca]

... that in today's age, when you go the supermarket/mall and the trolley's are all chained up requiring a "pound coin" to free one.

No I don't carry coins anymore and yes that makes it difficult.  Now I need to remember a bag and a pound coin.