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Comment by ya_throw | Hacker News Reader

It might be a technique thing, although you are correct that those maligned "modern" screw designs do not strip as easily.

It is crucial to get the right type and size of screwdriver - look for the markings on the screw to differentiate Philips from Pozidrive (mixing them up will chew up screws). Give a test wiggle before trying to turn the screw - there should be minimal slop, and the bit shouldn't immediately try to "cam out".

Apart from that, the trick is maximal downward force. Push the screwdriver into the screw as you're turning - most cross-head designs will try to "cam out" due to tapered sections of the interface, and that's what chews up the screws. I rarely strip screw heads, even on cheap consumer products.

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I learned the difference between Philips and Pozidrive at school, thank goodness, and this has saved countless stripped screw heads. I am surprised how few people know about it, even professionals.

It’s particularly important when using power tools. An electric drill with Philips bit will instantly munch a Pozidrive screw.

It is the 45 degree markings you’re looking for, in case that isn’t clear: https://shop4fasteners.co.uk/blog/pozidriv-vs-phillips/

Thank you for this. As an amateur I knew the difference existed, but I was never sure how to tell them apart. And if I had ever actually thought about it I would have googled, but it's one of those things that never occurred to me until I was knee deep into a repair.

JIS is still a thing as well. Look a lot like Philips except that it's way easier than normal to cam out.

Easier to cam out than Philips? Yuck!

It's generally better to cam out without wrecking the head than to cam out only under sufficient force as to tear up the slots.

Philips usually damage the head when camming out because as they cam out the total contact surface slowly goes to zero, so at some point the pressure exceeds the strength of the metal.

Right. In my experience, JIS screwdrivers lose contact faster if you're off-angle so they don't have the same opportunity to trash the head.

Exactly this - camming out as a protective feature is hugely over-blown and possibly totally false. In my experience, only the very cheapest of cheese-grade screws (a la Aliexpress) chew up without camming out.

camming out wasn't to protect the screws, it was to protect the sheet metal...

It's supposed to be much harder to cam out with JIS, unless you try to use a Philips screwdriver on a JIS screw (which will most definitely cam out and chew up). I treated myself to a JIS screwdriver, for the rare occasions I adjust my (Japanese) bicycle groupset.

JIS, as far as I know, is the technically superior cross-head design.

JIS screws will strip/cam out if you use a Philips, where I misunderstood this when replacing a rear lamp assembly on a 2016 Subaru, destroyed the JIS screw head where it had to be removed using the 10mm socket instead.

I've now used JIS bits for JIS screws and had no issues further than the initial.

> Give a test wiggle before trying to turn the screw - there should be minimal slop, and the bit shouldn't immediately try to "cam out".

This is the number one trick I've learned working at a repair shop. If you learn to do this, you can almost always get the screw out. In a worst case scenario, I've found that a flathead can sometimes get out a stripped torx screw, though don't try this unless there's no other option.

Thanks for the tips and for the more or less confirmation of my terrible technique. You're right that I pay no attention to Philips vs Pozidrive, will definitely need to start taking that into consideration. When following a guide, I do pay attention to exact bit sizes when they are mentioned , but for guide-less jobs I just go with "this looks like it fits". Will try out wiggling before committing.

I imagine it'll take a while to start to get a feel for it, wonder what's the best way to get a good amount of practice without damaging (useful) things.

Damage useless things? Seriously though, practice and experience are necessary, go and get some! Sadly that sometimes also includes learning how to figure out when you're out of your depth, which can be an annoying lesson to learn when you break something nice.

If you doing a lot of small screws I would suggest getting a Wiha precision screwdriver set. The iFixit set has great cost/value ratio, but there are much better tools on the market.

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