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Comment by Lionsion | Hacker News Reader

Important FYI for any Americans who don't know:

Ikea screws are not Phillips, they're actually Pozidriv, which is different enough to matter. Do not use a Phillips screwdriver to assemble Ikea furnature, as that combination will easily cam out and ruin the (typically soft metal) screw. It's easiest to buy the correct Pozidriv screwdriver bits from Ikea, but they're also available online.

My understanding is that Pozidriv is as popular in Europe as Phillips is in America. They look so similar that you probably won't know the difference unless you're told about it.

https://en.wikipedia.org/wiki/List_of_screw_drives#Pozidriv:

> Pozidriv and Phillips are not interchangeable. While Pozidriv screwdrivers fit Phillips screws, they may slip or tear out the Phillips screw head. Conversely, while Phillips screwdrivers will loosely fit and turn Pozidriv screws, they will cam out if enough torque is applied, potentially damaging the screw head or screwdriver.

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Ugh, except Pozidriv will still cam and tear up their own screws, and same with Phillips. That's the secret to this tidbit of information that is never included. They're both trash fasteners when used with a slightly different driver, but they're also trash even when used correctly.

Robertson for life. When I was young I had a job assembling furniture and that, along with a couple Allen socket fasteners, was the only thing we used. Phillips fasteners that came with assemblies went straight into metal recycling to hopefully get born again as something worthwhile. You can practically drive a Robertson head straight through the center of the Earth with the amount of torque it handles. Never have to waste time drilling pilot holes.

If I was made dictator for a day, I'd immediately outlaw Phillips and Pozidriv. Even flat head is better than those pieces of junk.

There are a lot of Phillips fasteners that will also fit a Robertson bit. Just try both with the same screw. It's ludicrous how instantly you'll realize the Robertson is better.

> Even flat head is better than those pieces of junk.

I would argue that flat head is the worst. They are not designed to be used with power tools.

Phillips isn't properly designed for power or hand tools. If it strips with a screwdriver, it's definitely going to strip with a drill. I've rarely seen power-driven Phillips screws that didn't have some sign of stripping, even using torque limiters and even on things fresh from the factory.

At least flat head takes uneven torque from hand tools well. It also allows improvised tools to be used in the field. If I'm working on say an off-road vehicle like a dirt bike, I'm going to tend to use just one size of hex bolt (usually 10mm) and flat heads for the screws.

I am not arguing for Philips. But flat head has 2 less contact surfaces so definitely even more easily to cam-out.

Nope, you are confused about the meaning of cam-out. Flat head is actually significantly less likely to cam out than pretty much any screw fastener type besides inverted hex (allen). Cam out is when the torque applied acts to ramp the driver out of the fastener. The problem with flat head is that drivers do not self center, making them poor choices for power tools. There's a reason flat head screws are still used extensively in firearms manufacture, and it definitely isn't a manufacturing convenience. Carefully driving a flathead screw is much less likely to damage the finish of the fastener, provided the correct driver is used.

Ah-ha, I might have mixed up with the screw "stripping" with cam-out but repeatedly cam-out is definitely the main reason to create a stripped screw. Evidently, the cam-out nature of the Philips screw is by design[1] to enable torque-limited application to prevent over-tightening, so it's a feature not a defect!

[1]: https://en.wikipedia.org/wiki/Cam_out

> Ugh, except Pozidriv will still cam and tear up their own screws, and same with Phillips.

That's true, but using a Phillips screwdriver with a Pozidriv screw is worse than either system by itself.

Robertson may be objectively better, but that's irrelevant to my point. I was I was addressing was one of confusion.

I think your comment more properly belongs at the root than as a response to mine.

Fair enough, You're probably right.

Last time I tried to use a Robertson screw from Home Depot in a heavy duty application (building an AC frame and decking), it cammed out and the square opening in the screw literally became round. I tried compensating by applying more downward force, but eventually it was still camming out and the bit itself became a cylinder.

It maybe better, but if the manufacturing quality is garbage, it's just as useless as the other ones.

I've only been using torx screws from 2012 onward. Never cammed out once and I'm still using 5 year old bits (they work like new)

Thanks for the feedback. I too switched to Robertson's but found no difference. It must be the quality of the screws and not the shape.

Huh. I've never had that happen once out of literally thousands of screws from all kinds of different sources, including HD. Should be impossible for it to cam because the walls of the cavity are perpendicular. There's no thrust force being generated.

Maybe it was just a really bad batch?

I have some R2 stainless "decking" (read: general construction) screws, and a standard consumer cordless impact driver generates enough transient torque to actually deform the cavity. Which even then results in the bit being "sticky" to pull out. I would imagine after several use cycles, the drive would be completely stripped.

While I generally agree that neither are great (I prefer Torx), are they not designed to protect whatever it is you are fastening from over-tightening bolts?

IMMO, IKEA should switch to use square drive or torx drive to better eliminate the risk of cam-out. Pozidriv is more complex to manufacture (than Philips drive) but arguably less resistant to cam-out than sqaure drive (easier to manufacture too) or torx drive.

Ikea sells a $8 tool set that includes three sizes of Pozidriv bits - and other bits that perfectly fit their various connectors. It's well worth the cost if you're planning to assemble anything you got from IKEA and not lose your mind.

They also have, or had, a circa $25 corded drill kit for sale (going by memory of briefly seeing, a year or two ago).

If someone doesn't have a drill and is contemplating purchasing and constructing a substantial piece of IKEA furniture, such as my parent's TV stand -- lots of bits to screw together. Under those circumstances, I suggest maybe they want to buy one of the drill kits.

I expect you can get a better corded drill elsewhere, and buy the relevant bits, for not much more. But, KISS, with regard to the amount of shopping to be done.

P.S. Well, what do you know. US $20, now, and cordless.

https://www.ikea.com/us/en/catalog/products/00196101/

IMHO if you're getting something for infrequent use, avoid batteries as they'll just go bad when sitting around unused.

That's a good point, in general.

In this case, I think there may be a few additional factors.

In the U.S., at least, many may view $20 as a "throwaway" level purchase to improve the assembly effort of the furniture they're purchasing/assembling.

Assembly is frustrating. A power tool and appropriate bits help, but then negotiating a cord takes it back somewhat in a negative direction. Plus, it's probably difficult and expensive to made and sell such a drill with a usefully long power cord. So, the purchaser then also need to negotiate acquiring and using an extension cord. And, you don't want them using the cord they use for that lamp in the corner; the drill's potential draw likely exceeds the rating of the extension cord most users will end up plugging it into.

IKEA has some language on the cordless drill's page specifically describing it being engineered to avoid idle battery drain.

People love cordless. Cordless sells. Many of them have no clue about what you describe, and meanwhile, cordless sells. :-/

Amazing that this has never met my attention. Why doesn't IKEA make this more clear?

Probably because there are little marks on the top of each pozidrive screws that indicate it is different. The don’t explain it in Europe either, it’s just a thing you should notice and account for when building stuff. I would put identifying pozidrive vs Phillips in the same camp as just knowing how to use a screw driver but perhaps I’m being harsh

Parochialism-induced harshness — what could go wrong? POZIDRIV® bits are practically unheard of here (Canada); you have to go out of your way to find them, on the level of triwing or pentalobe, or JIS.

I have triwing and pentalobe bits (Oregon), but this is the first time I've heard of POZIDRIV®, no wonder I've had so many Ikea mishaps.

I think from your comment you may be from Europe, so in that case for added context, you may be underestimating how uncommon Pozidriv screws and screwdrivers are in the United States. I have never seen a Pozidriv screw on any manufactured product other than Ikea furniture in the US. You cannot buy Pozidriv screws or drivers at major hardware stores (try searching "Pozidriv" on Lowes, Home Depot, or Ace Hardware), with the exception of one or two drivers that are in stock online only.

So consider that this is an extremely rare fastener format in the US market, and which looks almost identical to Phillips (the most common US screwdriver). I think many people like myself who are interested in tools and hardware are aware of Pozidriv and can identify it easily, but I can completely see why the average US consumer mistakes it for Phillips.

Yeah I’m in the UK, ok so probably as rare as square heads here then.

Interesting, I did not realize square drive was uncommon in the UK. It's a really nice screw head to work with, and as someone mentioned elsewhere in the thread, becoming more common in certain woodworking applications in the US.

It's a Canadian invention, and to this day quite localized to Canada, where it's nearly the standard for carpentry (at least, every deck screw I've ever seen here is Robertson drive). It's good that it's catching on, it has a few distinct advantages over Phillips, my favourite being that you can mount a screw on the driver and it will stay on the driver due to an interference fit, freeing your other hand to secure, support, or stabilize.

I found this out a few years ago after stripping several IKEA screws and getting incredibly frustrated. Bought a couple Pozidriv screwdrivers on Amazon, and they worked like a charm.

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