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Filing the corners off my MacBooks

kentwalters.com

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Re: Filing the corners off my MacBooks

#281

Post by simonbw »

thaumasiotes wrote: post #196
inatreecrown2 wrote: post #168

Lovely writing! And I think the understanding that one can and should modify their tools to their needs is rather rare and should be appreciated.

When I had a MacBook, I was quickly compelled to do something about the fact that its sharp edges scraped things, most notably scraping off the surface of my fingernails. But the obvious way to handle that problem is to put it in a case. For example: https://www.itslaut.com/products/crystal-x-case-for-macbook-... I wasn't thrilled with a product design that required a case to protect the rest of the world from the pr…

I have thought about filing/sanding my MacBook forever and getting a case to solve the problem never even occurred to me. I feel a little silly now because it does seem obvious, but also to me just filing it down sounds like less work than picking out a case.

Re: Filing the corners off my MacBooks

#282

Post by robotbikes »

sitharus wrote: post #250
normie3000 wrote: post #237

Earlier quoted context omitted.

> 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 ground…

I once had an HP with an aluminum case and it had a grounded power supply but if you plugged it in without grounding his an adapter (sometimes you gotta do what you gotta do). You could feel it straight up vibrate while conducting current if you rubbed your hand over it. Not enough to shock me but it felt like kind of a shoddy design and leaked a lot more current than I've felt on a MacBook.

Re: Filing the corners off my MacBooks

#283

Post by FloatArtifact »

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…

It's nice your co-workers are being blunt with you.

Re: Filing the corners off my MacBooks

#284

Post by simonbw »

convolvatron wrote: post #61
krackers wrote: post #29

There's a more thorough version of this at https://www.youtube.com/watch?v=RSaJAAqSAMw and the end-result doesn't look as tacky

if you want to do this, there is a better technique than shown in this video. get a single-cut fine file, maybe with a little more weight than the one in the video. single cut file has diagonal slots and allows firm and continuous contact with the piece. most files are double cut, have two sets of slots and look like bumpy diamonds. they remove more material but tend to bounce. use long even strokes with firm pressur…

I've been thinking of just using sandpaper stuck to a block of wood, though I imagine that might be slower.

Heck, a little part of me is tempted to try the smallest radius round-over router bit I have in a trim router, but the odds of that going horribly wrong are just way too high.

Re: Filing the corners off my MacBooks

#285

Post by userbinator »

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.

Really feels unsafe, but neither me nor the computer have suffered any serious injuries yet.

That's due to interference suppression capacitor in the PSU. The safety standard puts the "touch current" limit at something like 300uA (0.3mA), which is definitely in "painful but not dangerous" territory. You do need to exercise caution when plugging in other devices that are also connected to the mains, since that amount of current and voltage can certainly damage sensitive electronics.

Old but good page on such measurements: http://www.aplomb.nl/SMPS_leakage/Doc_ie.html

Re: Filing the corners off my MacBooks

#286

Post by Esophagus4 »

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

So glad to know it wasn’t just me with sweaty hands and pitted aluminum that is razor sharp!

Re: Filing the corners off my MacBooks

#288

Post by refurb »

I did something similar with drawer handles. I was living in a place with cheap furniture and the handles were aluminum billet cut to length and tapped so it could be screwed to the drawer face. The edge on either side were crazy sharp. If you bumped it with your knee you'd easily cut the skin.

So I took some 1000 grit sand paper for metal and gently wet sanded the edge. If you rotate it a little you can get a very small radius evenly around the edge and it will keep a nice finish that matches brushed aluminum.

I'd actually feel comfortable doing this to a Macbook having done it to the drawer handles. Just use little pressure, back the paper with something flat, and check your progress often. It takes very little to remove the sharpness to the edge, to the point it's hard to see with the naked eye.

Re: Filing the corners off my MacBooks

#289

Post by skavi »

overtone1000 wrote: post #249
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.

i’ll take 3. we can be boring together

Re: Filing the corners off my MacBooks

#290

Post by harha »

overtone1000 wrote: post #249
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.

Steer clear from co-worker 1..
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