Shown here: Dewalt MaxFit screwdrivers. They’re not completely related to the discussion, but seemed appropriate nonetheless.
A reader wrote in with a couple of great questions, the first dealing with broken screwdriver tips.
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Michael asked:
A couple of days ago at work I managed to badly break the tip of a Stanley Fatmax (black and yellow handle with red cap) when tightening a non-stuck flathead. I’m just wondering if it’s particular common for this model of screwdriver and if Stanley’s more recent models have remedied this. (Personally I have Craftsman ones at home that I got around 15+ years ago and haven’t had anything like this happen to them).
Stanley screwdriver sets are pretty cheap, such as this 10-pc set for $8 on Amazon, and this 20pc set for $14.10. That said, they shouldn’t be breaking when tightening a screw that’s not stuck.
Going by Michael’s description of the screwdriver being black and yellow with a red cap, it seems to have been a slotted flathead screw.
Slotted screwdrivers can be thin and wide, and with less “meat” than a Phillips screwdriver. I’ve seen more broken slotted screwdrivers than Phillips, which tend to instead wear out.
Screwdriver tips are often heat treated to be harder. Hardened tips wear slower. But, hardened metal can also be more brittle, and prone to breakage. The heat treatment needs to be carefully controlled so as to arrive at the perfect balance between hardness and toughness.
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With inexpensive screwdrivers, I would be reluctant to comment on consistency in a single batch, let alone over the span on several years. I really don’t know enough about the specific manufacturing processes.
I would also need to know more before I commented on the quality of the screwdriver.
How it was used before the breakage could give clues about why it broke. Maybe it was previously used on a hard fastener that had a bur, nicking the screwdriver tip. A little nick, a scratch, sometimes that’s all it takes to start a break.
Since this happened at work, were you the only one using it, or could someone have abused it in some way in their prior use? Even dropping it on a concrete floor could import some damage, and it wouldn’t necessarily be obvious.
Consider a pane of glass, acrylic, or other hard and brittle sheet material. Such sheets can be broken down to size by scoring a straight line. Then, over a straight edge, only moderate force is required to snap the sheet into 2 pieces.
Metal tools can sometimes behave in a similar way, where something can just break off.
If this was the first time the screwdriver was used, or it was only used in a very gentle manner before, then it’s probably just a junky cheap screwdriver.
If a tip is too brittle, it’ll break above a certain force. If it’s not hard enough, it’ll wear or deform quickly.
It could have also been a small defect in the screwdriver tip of some kind, at one specific spot. It happens.
A screwdriver that’s manufactured to retail for less than $1 as part of a set isn’t going to be very high quality. But it’s not supposed to just break very easily either. I would encourage you to contact Stanley for warranty replacement, but the shipping will cost you more than it’s worth.
Or maybe the screw was junky. Or the screwdriver wasn’t the right fit for that particular screw. That will happen too. A screwdriver might fit too shallowly, or it might not be wide enough for a screw.
This is a Stanley slotted screwdriver, with 3/16″ cabinet style tip. It tapers to a really small size. 1/4″ slotted screwdrivers will be a little thicker, and 5/16″ screwdrivers even thicker still. If a 3/16″ screwdriver is a little undersized for a particular screw, whether the fault of the user or size of the screw head, there will be a greater chance of breakage.
And once there’s a little too much force in one spot, it could be enough to break the entire tip.
How many slotted screwdrivers have you broken? Phillips? Other styles? I’d bet that smaller sized slotted drivers are broken the most.
AJ
Just broke a GardnerBender flat head electricians screwdriver. It had lived a hard life breaking open knockouts.
This is why we bring multiples to the jobsite!
I believe that this is why hollow ground / parallel ground screwdrivers cost more but someone can chime in on that subject.
Thomas J Walz
Excellent article.
I especially liked the explanation of possible damage modes.t
The #2 Phillips screwdriver is the most replaced screwdriver of all. It wears out and the wear is little nicks and chips.
In my experience most srewdrivers are beat up but nobody really examines them or cares until they break.
Stuart
Thank you!
Times like this make me wish I had time to dig deeper into fracture mechanics. Looking at fracture surfaces with an electron microscope was my favorite part of my PhD research.
With inexpensive screwdrivers, pointing out that “you get what you pay for” is the easy answer. But it doesn’t quite explain why the screwdriver broke when under seemingly light stress. Michael probably wouldn’t have given it a second thought if the driver broke when trying to break a screw free or when turning it super-tight.
Nathan
I’d buy that for a dollar -the brittlement thing. Also how many times did you use same said screwdriver as a pry device. Probably a few.
SO slotted drivers chipping off – I would say happens to most at some point. Now chipped/broken or just damaged beyond use.
different story. I’ve ruined quite a few phillips of various brands and styles and costs. Not bits (different again) but handled screwdrivers. And it’s because philps sucks mostly. I’ve also rounded out a few hex ball end drivers working on my RC cars back in the day. It can happen – I chalked that up to cheap driver – the expensive ones I bought are just dandy.
So I’ve gone though a few but not many – and with handled drivers I try to be more careful than I do with bit devices.
Emma
Not really directly relevant but this article claims that phillips were designed to camout on purpose. It was an early version of torque limiting.
Rest of the article is great to:
http://www.woodworkersjournal.com/todays-wood-screw-technology-2/
Alick
Emma, that’s a good article. I’ve read about the difference between philips and pozi in other places too. It’s more relevant than maybe you realise because screwdrivers designed for one type of screw don’t fit perfectly in the other and are more likely to slip and wear out.
fred
After 50+ years of using screwdrivers – and more recently screwdriver bits – you come to know that they are not often tools that last a lifetime. Cross point (Phillips, Pozidriv, Frearson, BNAE etc.) all are susceptible to wear. Hardened flat tips – particularly on some hollow-ground styles seem susceptible to being brittle – with chunks often cracking off. I’ve not seen it as much on hand screwdrivers – but quite often with insert and driver bits – which are really “consumables”. I know that good quality hollow-ground “gunsmith” screwdrivers seem to cost a lot more that what you typically purchase at the home center. Maybe its because they pay more attention to selecting blade materials for grinding, hardening and heat treatment.
BTW – I have noticed that hollow-ground insert bits do break more than the old style “keystone” bits that we used to chuck in bit braces and Yankee screwdrivers before the advent of cordless driver/drills.
Big Adam
I have a couple of Wera slotted chiseldrivers that take an absolute pounding.
So good, I’m thinking of investing in a full set:
https://www.amazon.co.uk/d/Hand-Screwdrivers/Wera-05018282001-Chiseldriver-Pound-Thru-Screwdriver/B0001NQQCC
Hilton
I bought that exact set from Amazon DE in December when they had a 20% off on certain hand tools. Note, the shafts are mostly 100mm so rather short but ideal for ‘outside’ work.
Alick
I’ve twisted 2 or three small slotted screwdrivers out of line on stuck screws, and had plenty of pozi / philips wear out, usually power driving hardened screws and not getting enough force behind the drill to keep it seated, but hand driven are just as vulnerable.
I think taking time to pick out a driver that’s exactly right for the screw helps – like pozi and philips have different design principles so don’t mix and match the drivers. Japanese JIS standard tips fit noticeably better in screws from Japanese products.
Slots are worst because selecting a driver on the width of the blade doesn’t necessarily fill the slot – i’m trying to say ideally you match the width and thickness of the slot …
One piece of kit I really rate just now. I ordered something online and the vendor included a 3 pack of makita power bits as a freebie / promo. They are double ended, gold color, with a narrow torsion zone in the middle. These things are awesome. Great fit in pozi screws and really stand up to wear. I’m ready to buy more but they just last and last.
fred
You are right about not all cross-point screws being the same.
I did a lot of Bicycle repair.
While mostly hex-socket head and torx screws more recently – there were cross-head screws too.
On French bikes – it was B.N.A.E. bits that fit best
On Japanese bikes – it was JIS
On old USA-made bikes it was Phillips
On some other European bike it was Pozidriv
And on some auto trim it was Pratt-Read Frearson
Koko the Talking Ape
I’ve broken one slotted head, and twisted another so it wasn’t flat any more. It’s that hardness vs. toughness thing, I guess. I’ve worn out dozens of Phillips heads, both screwdrivers and bits.
Has anybody has worn out a Robertson (square) or torx head?
Blythe M
I’ve worn out lots of torx bits, but mostly because of high volume of screws combined with off angle driving. I don’t think I’ve ever worn out or broke a Robertson tip, which is why they are my favorite for critical no strip applications
fred
I’m sure folk know that there are also “Torx Align” and “Torx Plus” bits/screws that have difference from the original Torx design.
Koko the Talking Ape
I did not! Thanks!
Rick
I break them or cam them out all the time; no such trouble with torx, even when abused in my impact.
Ed S
Grind it down to use as screw starter. awl, ice pick…!
Nathan
I have worn out a torx bit but never a torx driver – but I don’t know I have a torx driver.
the bits though – even though hard steel – wore down. I actually blame the screws more than the drive bit. IE poorly made screw head probably on the outside edges of “tolerance” and my bit being probably near mid spec. but slop induced. and over time and many other screws with wobbly interface – and bam – wear on the torx points – more slop and finally it’s worming out. Worse – I’ve spun a few torx bits with my impact driver. same thing I think tolerances.
ca
I don’t know why anyone still makes slotted screws. They must be a masochist.
Hilton
It gives us CDO types the opportunity to clock out screws.
Hilton
OUR screws idiot!
fred
Good for reproduction furniture or replacing hardware on antiques.
Big Adam
I live in a 200yr old historic property. You don’t re-hang doors with shiny pozidrive screws!
Goodnightjohnboy
Screwdrivers that are made in China break because the Chinese don’t know how to make steel that’s worth a darn. This is an absolute fact. They chrome them right after they quench without re-temperering. Which is why they just chip. I’ve got some that are pretty old that I use. I’m talking non-painted wooden handle old. Can’t break em if you tried to. Damn good American made steel. I bought a Dewalt set about 2 years ago and the tips either chipped off or the cheap plastic handle came off the shaft or they bent. Screwdrivers shouldn’t bend. Trash. If you want a good screwdriver set besides Klein (which charge way too much) get some euro-made or old American made at a garage sale.
Kevin Durette
Agreed! This whole article should have stopped here: “A screwdriver that’s manufactured to retail for less than $1 as part of a set isn’t going to be very high quality.” The market keeps pushing prices down, but then everyone complains when they find out their shiny tools are trash. Buying junk is a waste of money in the long run.
I picked up my Klein screwdrivers from a pawn shop.
BonPacific
I’ve mostly had philips screwdrivers break. Often one wing will chip out on me. The only problems I have with slotted screwdrivers is when the tip bends over time and use. That said, i don’t think I’ve ever bought a screwdriver, just digging into the box of the things I’ve inherited over the years.
John S
I do a lot of computer and electrical repair work and I constantly break or shear the philips and JIT micro bits. I don’t know if its just the quality of metal or the bad QA on the production. I’ve tried just about every brand and they all seem to use that cheap chromed process to create them which either makes the very tip weak or lends to slipping (lending to shearing the tool wings and tip or coming out the screw head) in the screw head instead of a positive bite.
Hang Fire
For electronic screwdrivers, try Wiha. They are worth the price difference. Not only do the tips hold up longer, the rough finish gives you better grip on the fastener.
John S
Wiha definitely are better as are Wera (but that stupid proprietary halfmoon / HIOS drive connector ugh). But Wiha only appears to only put the stuff like micro finish, pico finish, and saves their high end stuff for their full screwdrivers and not their stand alone micro bits (Phillips – 000, 00, 0 and JIS – J000, J00, J0 sizes). Those I use in things like micro torque and electric driver equipment as well as bit drivers for normal routine stuff. So while I do use a lot of Wiha, I really wish they’d add that attention to detail on these individual micro bits.
Hang Fire
I have several cabinet tips with twisted ends of all brands, and many Philips with worn down tips. But broken, I can’t remember the last time I actually broke a screwdriver.
By the way I despise cabinet tips (slotted, wedge shaped screwdriver tips). They are designed to cam-out of the screw slot, damaging the fastener.
Parallel ground screwdrivers should entirely replace cabinet tips. They are stronger, don’t cam out, and rarely damage the fastener.
fred
I think cabinet tips (sometimes called electrician’s tips) were actually an evolution from the original keystone or mechanic’s tip design – which tapered to the tip on both planes. Hollow-ground screwdrivers – sometimes also called gunsmith or watchmaker’s screwdrivers – as you say – have faces that are parallel at their tips – and fit screw slots more precisely. I suspect that it is a matter of cost that keeps them from replacing other styles. The old Keystone tip screwdriver does do a better job in prying open paint can lids.
Ken
Still using my very first set of Stanley (England) screwdrivers from around 1980, and haven’t broken or worn out a single one, not even the Philips #2. I’ve worn out/broken plenty of bits in cordless screwdrivers or impact wrenches, but you expect that after driving a few hundred drywall or deck screws…
A W
I broke several new DeWalt maxfit #2 Phillips bits driving 4″ screws into pine. They would experience brittle fracture, taking out about a third of the bit. I was surprised. I had better luck with Robertson (square) drive screws, and have since switched to Milwaukee shockwave bits.
Jeremy Brown
6 slotted screwdrivers this year, 10 slotted impact bits, 6 slotted bits from Milwaukee screwdrivers with the multiple changeable bits. Two Philips bits, one screw driver rounded off.
None used for prying.
Best bang four the buck in hand ones for me have been Megapro brand bits, they last over a year, far better than Milwaukee.
We’ve worn out dozens of Philips, usually the edges round slightly and the bit spins. A few times of this happening and they must be replaced. and a few Robertson(square drive) for the same reason.
Interestingly in order of fasteners, we see probably 50:10:1 Robertson, Phillips, slotted in the shop.
Even more interestingly there are a few hidden gems for bits.
When it comes to Philips, no question the Makita gold, double ended impact bits are absolutely the best.
On cruise ships we are driving them with massive impact guns and pulling thousands of fasteners. Dewalts and Milwaukee shockwave(very prone to rounding out) bits last 100-200 fasteners at max before splitting, mastercraft bits around 50, Were bits 30-300(they fail right away or last better, no middle ground) and Makita gold unknown, we only broke one, so at least 1000 fasteners.
For Robertson the two piece bits, color coded with black hardened tips last extremely well, on the order of 10x longer than one piece bits of any brand. Suspect it’s due to better fit which also makes it’s easier to drive one handed.
Joe J
You can sometimes extend the life of a philips head with a bit of filing.
If they are really bad they make good awls.
If you are messing up a lot of screwdrivers (like #2 phillips) Just go with replaceable bits and buy the big packs of them. No point in dickering your good screwdrivers.
Wayne
When I’m working around knuckleheads with worn out screwdrivers, it’s usually because the guys/tools are cheap and they never bother to get the right sized tool for the screw.
Whether broken or worn out, the wrong size can be just as much a culprit as cheap.