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Filing the corners off my MacBooks

kentwalters.com

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Re: Filing the corners off my MacBooks

#241

Post by msephton »

normie3000 wrote: post #237
CGamesPlay wrote: post #200

Earlier quoted context omitted.

Oh is that why it happens? Was wondering why the spot directly under my wrist was pitted into a sawblade. I also filed it, though just enough to remove the pitting, nothing like the OP did. It's easy for me to feel the mains frequency while gently rubbing the top surface of the MacBook while it's plugged in. Really feels unsafe, but neither me nor the computer have suffered any serious injuries yet.

> It's easy for me to feel the mains frequency while gently rubbing the top surface of the MacBook I haven't been a regular Mac user, but I've had maybe 3 work MacBooks since 2010 and I recall having this issue with all of them. Why haven't they fixed it?

It's also an issue on the new Neo. It was the first thing I noticed when I tried one in the Apple Store. I unplugged the power cable and it went away, replugged and it came back. I'm in the UK so I expected grounded electricity supply.

Re: Filing the corners off my MacBooks

#242

Post by 15155 »

Tsiklon wrote: post #225
imglorp wrote: post #216

Earlier quoted context omitted.

How? The (US) charger's only got 2 pins so ground stays unconnected.

The extension cable they used to include in box with the computers, it has the third pin for the charger brick connector which is wired to ground

There's zero chance that the DC ground in the laptop is tied to earth ground in the charger: they use LLC resonant converters and flyback converters (depending on vintage) - an earth ground tie would defeat the purpose of these isolated topologies.

Re: Filing the corners off my MacBooks

#243

Post by ddlsmurf »

russelg wrote: post #238
ddlsmurf wrote: post #228

Earlier quoted context omitted.

but it's never going to be grounded, there isn't even a ground pin on the charger

If you swap in the extension cable head, that does indeed have a ground pin, at least in Australia anyway. The grounding comes from that metal ring that the connector uses as a guide. https://www.apple.com/au/shop/product/mw2n3x/a/power-adapter...

only two prongs of which make it through. Usually the regulation as I understand is that it's fine if you can prove the case can never get in contact with anything electric, for most laptops that's just being made of plastic.

Re: Filing the corners off my MacBooks

#244

Post by fy20 »

kokanee wrote: post #72
html5cat wrote: post #46

Not all heroes wear capes. This is excellent and can't wait to get aluminium mac next to try it – don't think Space Black is a good way to go. Author's another post on "The Seasons are Wrong" [0] is excellent too and I fully support both approaches. [0] https://kentwalters.com/posts/seasons/

The seasons idea is interesting -- to me, both proposals feel wrong. I think it's because the weather changes that I perceive seem to lag behind the changes to daylight length by a few weeks. I would propose boundaries that align partly with how I perceive the weather, and partly with how we plan our year (by months): Summer starts June 1st, Fall starts September 1st, Winter starts December 1st, and Spring starts Mar…

In my country the dates you stated are what are considered the start of the seasons. This year there was a very clear change between winter and spring on March 1st. February was cloudy and minus, March was sunny and plus.

Re: Filing the corners off my MacBooks

#245

Post by dazilcher »

hk1337 wrote: post #49
bee_rider wrote: post #12

Earlier quoted context omitted.

I think he is not worried about the resale value. > This was on my work computer. I expect to similarly modify future work computers, and I would be happy to help you modify yours if you need a little encouragement. I don’t understand the actual decision but I appreciate the gusto with which it was made.

The main reason to consider resale value is 1-2 years later you may want to upgrade and selling it to another person typically yields you more money than trading it in with Apple. Doing something like this may decrease how much you could sell it for later. If you’re not planning on doing that then it’s not really a factor for you.

> work computer

Re: Filing the corners off my MacBooks

#246

Post by leptons »

CGamesPlay wrote: post #200
420official wrote: post #144

I just did this to my MacBook not because of the sharp edge but because the pitting turns a sharp edge into a sawblade. Something about the grounding on on the frame when plugged in mixed with my sweaty hands leads to damage along this sharp edge on every MacBook I've ever owned. See https://www.reddit.com/r/macbook/s/hbyVh5SJhw for another poor soul with the same caustic skin

Oh is that why it happens? Was wondering why the spot directly under my wrist was pitted into a sawblade. I also filed it, though just enough to remove the pitting, nothing like the OP did. It's easy for me to feel the mains frequency while gently rubbing the top surface of the MacBook while it's plugged in. Really feels unsafe, but neither me nor the computer have suffered any serious injuries yet.

Maybe you're holding it wrong? j/k

Seriously though, that does not sound safe at all.

Re: Filing the corners off my MacBooks

#247

Post by bragr »

ddlsmurf wrote: post #243
russelg wrote: post #238

Earlier quoted context omitted.

If you swap in the extension cable head, that does indeed have a ground pin, at least in Australia anyway. The grounding comes from that metal ring that the connector uses as a guide. https://www.apple.com/au/shop/product/mw2n3x/a/power-adapter...

only two prongs of which make it through. Usually the regulation as I understand is that it's fine if you can prove the case can never get in contact with anything electric, for most laptops that's just being made of plastic.

As has been established in other threads here, the metal button thing the prongs slide onto is an earth connection.

Re: Filing the corners off my MacBooks

#249

Post by overtone1000 »

jasoneckert wrote: post #222

Thanks for this interesting post - I've been showing it to co-workers to get their reactions, which was incredibly entertaining for me! Co-worker 1: Interesting. I wonder if that voids the warranty. It's Apple you know. Co-worker 2: May Jobs have mercy on their soul... Co-worker 3: Not a bad idea. But not sure if that would cause problems with structural integrity of the laptop, like if you drop it or something. Co-w…

Co-worker 4 is the one I want to have a beer with.

Re: Filing the corners off my MacBooks

#250

Post by sitharus »

normie3000 wrote: post #237
CGamesPlay wrote: post #200

Earlier quoted context omitted.

Oh is that why it happens? Was wondering why the spot directly under my wrist was pitted into a sawblade. I also filed it, though just enough to remove the pitting, nothing like the OP did. It's easy for me to feel the mains frequency while gently rubbing the top surface of the MacBook while it's plugged in. Really feels unsafe, but neither me nor the computer have suffered any serious injuries yet.

> It's easy for me to feel the mains frequency while gently rubbing the top surface of the MacBook I haven't been a regular Mac user, but I've had maybe 3 work MacBooks since 2010 and I recall having this issue with all of them. Why haven't they fixed it?

They can’t, it’s caused by the capacitors required to suppress electromagnetic interference caused by the switch-mode power supply. These allow a very very tiny amount of current to leak through from the mains side, which is then capacitively coupled to the metal case (IIRC Apple do not connect the case to power negative) reducing it further, but it’s enough for humans to sense it.

It can be avoided by using a grounded power supply, but because there are large countries that have ungrounded outlets in common use the most designs are ungrounded.

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