Stuck screws

[nestork]

I believe that if the OP was using Robertson drive screws, this thread would have never even been started.

[J Burns]

If they were Robertsons, they probably would have snapped. A lot of the Robertsons sold in America come from China, bought on the low bid.

Square socket screws had been invented before Robertson, but he figured out how to manufacture them.

Phillips was concerned with producing a screw that a spinning bit on a machine could engage and that would cam out when it reached a certain torque. He turned it over to American Screw in Providence to work out the manufacture. About the same time, Frearson had a cross screw that wouldn't cam out. He turned it over to Reed and Prince, 40 miles up the river in Worcester.

Ford turned from Robertson because he couldn't get a license to ensure his supply. Was he afraid of depending on a sole source, or was he afraid of possible tariffs?

Reed and Prince became common in maritime use, where nobody wanted screwdrivers to cam out. Robertsons might have been better because sailors wouldn't have mistakenly used Phillips drivers. If there were few Robertsons in America and few cross screws in Canada, I wonder if tariffs were an obstacle.

[nestork]

I expect Canada gets it's Robertson screws at the same price from the same place that the USA gets theirs, and in my whole life I've only had one Robertson screw break on me when I was tightening it. I've never had a Phillips or slot drive break, but that's mostly because I could never put nearly as much torque on either of those drives with the screw driver.

J Burns;3310265 Wrote:

If only he would have designed it to cam out at a HIGHER torque. It's that problem with the screw driver camming out of the screw drive that is the Achilles heel of Phillips screws. That's why I avoid using them if possible.

J Burns;3310265 Wrote:

My understanding is that Henry Ford wanted a license to manufacture the Robertson screws in his own shops so that he could ensure his supply of them. Robertson didn't want to give Ford the license to do that because he'd have no way of knowing how many screws Ford would make. Robertson wanted to be paid for each screw that Ford would make, but he didn't trust Ford to accurately report that number, and hence the amount he owed Robertson. In the end, neither man trusted the other and the result has been that it wasn't until the Torx drive screw came out about

70 years later that the USA had a truly decent screw drive to use.

In my opinion, Torx is just as good a screw drive as Robertson. But in my opinion, it's a crying shame that the USA is still needlessly struggling with stupid Phillips and slot drive screws for so many years, neither of which are easy to use.

J Burns;3310265 Wrote:

I don't believe tariffs played a big part in this. I believe this was a chicken and egg problem. Americans didn't buy Robertson screw drivers because they seldom encountered Robertson screws. Simultaneously, manufacturers avoided using Robertson screws because they knew most Americans wouldn't have Robertson screw drivers. That's still the case. Everything I buy here in Canada that's made in China for export to the US market comes with slot and Phillips screws. That's because the Chinese know that Robertson screw drivers aren't very common in the USA, so the Chinese use Phillips and slot drive screws instead. So, put this one in the same bag as "Which came first, the chicken or the egg?" Robertson drive screws were never popular in the USA, and so people didn't buy Robertson screw drivers and so manufacturers didn't use Robertson screw. It's kinda the same thing with the Qwerty keyboard. The only reason we still use it is because so many people know how to touch type having learned to type on Qwerty keyboards.

Anyhow, I guess it's water under the bridge no matter how you look at it.

[J Burns]

I've snapped several Phillips wood screws over the years, extracting them with a manual screwdriver. My BIL is a carpenter who likes Robertson screws for some purposes but almost always uses Phillips. With a power driver, camming acts as a clutch to keep him from breaking the screw or driving the head of the screw deep into the wood. In drywalling, he can put mud on a Phillips screw without having it bubble.

Growing up, I didn't like slotted or Phillips screws. We had various cheap screwdrivers around the house. I bought a set of 6 Stanley screwdrivers. I hated them. I saw another set of 6 Stanley screwdrivers that didn't cost much more but looked better. I bought them and found out what a difference good screwdrivers can make.

The Reed and Prince, available since the 1930s, doesn't cam out. Phillips developed its own non-camming screw, the Posidriv. It looks like a Phillips and, unlike the Reed and Prince, works with a Phillips driver. For torque, crosshead screws have an advantage in that the blades are at right angles to the torque.

The Torx was invented as tamper-proof version of the Allen, first produced in 1910 in Hartford. The BMW motorcycles I've owned had only slot screws, Allen screws, and hex cap screws. With a good screwdriver and a good screw, I could apply as much torque to a slot screw as to an Allen screw. The advantage to the Allen screw is that an Allen wrench twists like a torque wrench when it's tight enough.

Riders used to have trouble with screws on Japanese motorcycles because they were using Phillips drivers on crosshead screws that weren't Phillips. It's important to feel whether a blade really fits a screw.

[Kurt Ullman]

Well this is my wife's idea so... (grin)

[Stormin Mormon]

Buy her a brush for Christmas? I mean, a vacuum cleaner just isn't enough presents.

- . Christopher A. Young Learn about Jesus

.

[notbob]

Likewise.

OTOH, I don't know if phillips head screws were created to cam out at a certain torque or to merely make production assembly easier on the assemblers. Only gotta turn the tool 90°, at most, to engage screw. I do know I never saw a phillips head scew until I ran across Japanese motorcycles, which make extensive use of phillips oval head screws, which require painfully tight tolerances to get properly alaigned w/ the screw holes.

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[J Burns]

Camming out made production assembly easier. Wringing the head off a screw or stripping threads is inconvenient.

Japanese motorcycles don't have Phillips screws. They have JIS B 1012. It costs $44 to see the specs.

It would cost another $65 to see the specs for Pozidriv (ANSI Type 1A), but I can't tell the difference.

If you go into a store, even a Japanese motorcycle shop, and ask for a JIS screwdriver, they'll probably advise you to go screw yourself because there's no such thing.

You could spend time and money ordering them on line, but PZ bits fit JIS screws so well that I think JIS is just another name for Pozidriv. Both are designed not to cam out. PZ bits are common and cheap in America. Some deck screws use them. I've read that PZ is popular with European manufacturers.

People have had trouble with crosshead screws because the screwdriver they use may not fit the screw they have. I've read that Robertson users are having a similar problem. Bosch, Irwin, and Home depot have been shipping square bits to Canada. They look like Robertson bits and work fine on American screws, but they damage Robertson screws.

[notbob]

Well, excuse me Mr. Pendantic!

I'll call 'em cross-slot-driver oval heads. They still look like a phillips head and they were a PIA if one didn't have a hammered or pneumatic impact driver to get 'em out. Until I got one (eventually both), I stripped a lotta those cross slots. The surface contact friction of the countersunk face, along with the assy torque, made for a screw that was quite difficult to remove w/o stripping.

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[TimR]

He's really not being pedantic though. There really is a difference between phillips and posidrive and the phillips really will strip them.

As you found out.

[J Burns]

When friends would ask me to work on their Japanese motorcycles, I loved the way the crosshead drivers that came with the bikes fit. I didn't mess up any screws with Phillips drivers because I could feel that the fit was bad. (I've read a Phillips may work if you grind down the point.)

I have impact drivers, but I've often skipped the hammering and used them as screwdrivers. The important thing is that the bits fit because they are PZ, even if they aren't marked. If it feels good, do it!

I didn't round off any Japanese nuts with SAE wrenches because I could feel that the fit was bad. Is that pedantic or what!

[notbob]

???

I was japanese motorcycle mechanic. I've NEVER seen a Japanese tool that was worth spit. Even Japanese impact bits would twist after repeated use. I always bought Korean made imp drivers. I still have the same one I use 40 yrs ago. Tip: Use the next size larger cross bit. Still fits and doesn't reach the bottom.

No. I bought metric tools. I never even owned SAE wrenches until I bought a Harley. By then, only half the fasteners on a HD were SAE. Metric will fit both. Sometimes a tad bit loose, sometimes a tad bit snug, but they always would fit.

True pendantic would be to buy flank-drive box wrenches. Bonney invented 'em and guarded the jealously guarded the patent for yrs. Since they also made SnapOn's combo wrenches, SnapOn was the first to have flank-drive (that's SO's name for them, too. Bonney called 'em something else) when Bonney's patent expired. Now, most tool companies have a version.

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[J Burns]

They fit, but naturally weren't big enough for all jobs.

Your English is very good!

Have you tried Vessel? In business since 1916.

It's unfortunate that their customer-service line is at the Fukuoka Office. I imagine they've lost a lot of American business by answering the phone, "Fuck you, OK?"

In the 80s, I bought a big, cheap set screwdrivers from Harbor Freight. Square wood handles, square shafts, flat black. Their quality is so good that I've often sat by the stove drinking beer and admiring them and contemplating becoming a Communist.

I had a beautiful #3 SnapOn crosspoint screwdriver, but I gave it to my BIL. That's okay, my impact sets have bits from 1 to 4.

I can tell the clowns who overtorqued my lug nuts weren't using flank-drive sockets. They deformed the corners of my nuts. Maybe Bonney got the idea by examining the hollowed corners of worn-out impact sockets.

[notbob]

You should see me with a pair of chopsticks. ;)

I'll admit the Japanese make some good things. Mitutoyo, Honda, SKB Firearms, etc. I also have a closet full of dead Japanese junk, stuff that never made to the warranty date.

Too bad HF no longer promotes such quality. And yes, now that I'm retired, I no longer buy pro quality tools and will buy things from HF. All it takes is to be smarter than the tool. ;)

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