When does a screw become a bolt?
- Thread starter rgranger
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This is entirely my own personal interpretation.
Since this thread seemed more for fun than technicality, I went with my own thoughts, which are rarely technically correct! Sorry if anybody thinks I'm an authority!I think @Dalliance is probably closer to the technical definition!
Funny, I googled it, too, and the one that stuck in my head was that a bolt has an unthreaded portion, or shank, and a screw does now.
I think the answer is - "it depends."
ChatGPT seems to be overloaded this afternoon, so just for fun I figured I’d try the newer competing service, Google Bard. The response was not encouraging-
“…The most obvious difference is that screws have a helical ridge, or "thread," that wraps around the shaft of the fastener. Bolts, on the other hand, do not have threads. Another difference is that screws are typically used in conjunction with a nut, while bolts are not…”
I’ll report back after ChatGPT is answering questions again. Hopefully it’s not as hilariously wrong.
“…The most obvious difference is that screws have a helical ridge, or "thread," that wraps around the shaft of the fastener. Bolts, on the other hand, do not have threads. Another difference is that screws are typically used in conjunction with a nut, while bolts are not…”
I’ll report back after ChatGPT is answering questions again. Hopefully it’s not as hilariously wrong.
as well.
Chat GPT is not perfect but closer -
“Screws and bolts are both types of fasteners used to join two or more objects together, but they differ in a few key ways.
A screw typically has a pointed tip and a helical thread that wraps around its cylindrical shaft. The thread is designed to grip the material it is being screwed into, allowing the screw to be turned and driven into the material. Screws are typically used to fasten two or more objects together by being screwed into one of the objects and then into the other.
A bolt, on the other hand, is a type of fastener that typically has a smooth shaft and a threaded end. Bolts usually have a flat, hexagonal or square-shaped head that can be turned with a wrench or pliers. Unlike screws, bolts are used in conjunction with a nut, which is threaded onto the end of the bolt and tightened to secure the objects being fastened together.
In summary, the main difference between a screw and a bolt is that a screw is designed to be turned directly into the material being fastened, while a bolt is used with a nut and is typically inserted through a hole in the material before being secured.”
Although if you want toChatGPT does have some extra “fun” features, like “now give me the answer in a format that would be good for an internet flamewar”. Answer-
“Are you kidding me? It's pretty obvious that screws and bolts are two entirely different things. A screw has a pointy end and a helical thread, while a bolt has a smooth shaft and a threaded end with a hex or square head. If you can't tell the difference between the two, then you have no business getting involved in any kind of DIY project. So why don't you go back to your kindergarten class and learn your basic hardware, huh?”
“Screws and bolts are both types of fasteners used to join two or more objects together, but they differ in a few key ways.
A screw typically has a pointed tip and a helical thread that wraps around its cylindrical shaft. The thread is designed to grip the material it is being screwed into, allowing the screw to be turned and driven into the material. Screws are typically used to fasten two or more objects together by being screwed into one of the objects and then into the other.
A bolt, on the other hand, is a type of fastener that typically has a smooth shaft and a threaded end. Bolts usually have a flat, hexagonal or square-shaped head that can be turned with a wrench or pliers. Unlike screws, bolts are used in conjunction with a nut, which is threaded onto the end of the bolt and tightened to secure the objects being fastened together.
In summary, the main difference between a screw and a bolt is that a screw is designed to be turned directly into the material being fastened, while a bolt is used with a nut and is typically inserted through a hole in the material before being secured.”
Although if you want to
ChatGPT does have some extra “fun” features, like “now give me the answer in a format that would be good for an internet flamewar”. Answer-“Are you kidding me? It's pretty obvious that screws and bolts are two entirely different things. A screw has a pointy end and a helical thread, while a bolt has a smooth shaft and a threaded end with a hex or square head. If you can't tell the difference between the two, then you have no business getting involved in any kind of DIY project. So why don't you go back to your kindergarten class and learn your basic hardware, huh?”
Interesting. I don’t think an everyday person would use the phrase “helical thread….” Rather, “spiral thread….”, and so forth. As in spiral staircase versus helical staircase. I think it’s becoming an important skill to know colloquial phrasing from “AI talk.” That is, to recognize the latter.
The U.S. Customs and Border Protection issued An Informed Compliance Publication, March 2006, What Every Member of the Trade Community Should Know About: Distinguishing Bolts from Screws, which states…
U.S. Customs and Border Protection uses fastener industry standards to distinguish bolts from screws. When a fastener is described in a fastener industry dimensional standard as either a screw or a bolt, we follow that standard. When we have no dimensional standard, we go to "Specification for Identification of Bolts and Screws," ANSI - ASME B18.2.1 1981 (the "specification"). In Rocknel Fastener, Inc. v. United States, Slip Op. 00-112 (Ct. Int'l Trade, decided August 29, 2000), the court sanctioned ANSI/ASME Standard B18.2.1 as "provid[ing] a well-recognized, comprehensive basis for the common and commercial meaning of bolt and screw as understood by the fastener industry in the United States."
Since the United States Court of International Traderecognizes ANSI - ASME B18.2.1 1981 as "provid[ing] a well-recognized, comprehensive basis for the common and commercial meaning of bolt and screw as understood by the fastener industry in the United States," we can describe bolts and screws thusly…
A bolt is a fastener that has external threads (a nut, for example, has internal threads), is inserted into an unthreaded hole of one or more parts, and is tightened or loosened by turning its nut. Carriage bolts, elevator bolts and plow bolts, for example, are bolts because you can't turn their heads to tighten or loosen them.
A screw has external threads just like a bolt. But a screw is inserted into a threaded or unthreaded hole, and is tightened or loosened by turning its head. It may or may not be used with a nut. Wood screws and sheet metal screws make their own threads in the hole, so they are not used with a nut. Machine screws and cap screws, for instance, thread into threaded holes or are used with a nut. In either case, though, you tighten or loosen the screw by turning its head.
With regard to Hex Bolts and Hex Cap Screws it is commonly accepted that it's a Hex Cap Screw if it has a washer face bearing surface and if it doesn't it's a Hex Bolt. That belief is supported by ASME Standard B18.2.1.
Naturally there are exceptions to every rule as the Millwrights and Mechanics Guide 4th Edition observes: "These definitions obviously do not always apply, since bolts can be screwed into threaded holes and screws can be used with a nut." And several other examples come to mind: A toggle bolt consists of toggle wings, which is a special spring-loaded collapsible nut, and a screw—you always tighten the screw, but the assembly is called a toggle bolt. Stove bolts are machine screws supplied with machine screw hex nuts. Lag screws are sometimes called lag bolts. And fully-threaded cap screws are also called tap bolts.
Most of the fasteners at Fastener Mart follow the bolt/screw rule. But even if they don't, we've worked hard to make it easy for you to find what you're looking for.
And of course now that the United States Court of International Trade has ruled, we suppose the question is: Has the bolt/screw debate finally been put to rest?
U.S. Customs and Border Protection uses fastener industry standards to distinguish bolts from screws. When a fastener is described in a fastener industry dimensional standard as either a screw or a bolt, we follow that standard. When we have no dimensional standard, we go to "Specification for Identification of Bolts and Screws," ANSI - ASME B18.2.1 1981 (the "specification"). In Rocknel Fastener, Inc. v. United States, Slip Op. 00-112 (Ct. Int'l Trade, decided August 29, 2000), the court sanctioned ANSI/ASME Standard B18.2.1 as "provid[ing] a well-recognized, comprehensive basis for the common and commercial meaning of bolt and screw as understood by the fastener industry in the United States."
Since the United States Court of International Traderecognizes ANSI - ASME B18.2.1 1981 as "provid[ing] a well-recognized, comprehensive basis for the common and commercial meaning of bolt and screw as understood by the fastener industry in the United States," we can describe bolts and screws thusly…
A bolt is a fastener that has external threads (a nut, for example, has internal threads), is inserted into an unthreaded hole of one or more parts, and is tightened or loosened by turning its nut. Carriage bolts, elevator bolts and plow bolts, for example, are bolts because you can't turn their heads to tighten or loosen them.
A screw has external threads just like a bolt. But a screw is inserted into a threaded or unthreaded hole, and is tightened or loosened by turning its head. It may or may not be used with a nut. Wood screws and sheet metal screws make their own threads in the hole, so they are not used with a nut. Machine screws and cap screws, for instance, thread into threaded holes or are used with a nut. In either case, though, you tighten or loosen the screw by turning its head.
With regard to Hex Bolts and Hex Cap Screws it is commonly accepted that it's a Hex Cap Screw if it has a washer face bearing surface and if it doesn't it's a Hex Bolt. That belief is supported by ASME Standard B18.2.1.
Naturally there are exceptions to every rule as the Millwrights and Mechanics Guide 4th Edition observes: "These definitions obviously do not always apply, since bolts can be screwed into threaded holes and screws can be used with a nut." And several other examples come to mind: A toggle bolt consists of toggle wings, which is a special spring-loaded collapsible nut, and a screw—you always tighten the screw, but the assembly is called a toggle bolt. Stove bolts are machine screws supplied with machine screw hex nuts. Lag screws are sometimes called lag bolts. And fully-threaded cap screws are also called tap bolts.
Most of the fasteners at Fastener Mart follow the bolt/screw rule. But even if they don't, we've worked hard to make it easy for you to find what you're looking for.
And of course now that the United States Court of International Trade has ruled, we suppose the question is: Has the bolt/screw debate finally been put to rest?
So how do you tighten the nut on a bolt of lightning? 
I read some of these comments to my wife last night. She made me sleep in the car that was parked in the attached garage. She is so sweet she even turned on the engine and the heater so I do not get cold and closed the garage doors.
Like deck screws?What about fasteners installed with torx, Robertson, and other screwdrivers ?
What if you use a drill driver to install the Phillips screws, instead of using a screw driver ? Does that make the fasteners, drills instead of screws ?
A “screw driver” is that which drives the screw into the material. It can be manual or powered. A drill if so used is a powered screw driver; the manual version is just what we think of when using the familiar “screw driver” tool.
Is a driver's license needed when using a screw ?
What about bolts of cloth ? Explain that with yer helical whatchamacallits
What about bolts of cloth ? Explain that with yer helical whatchamacallits
I was bored... so I started this thread. Who knew we could talk about screws for 37 posts?
I guess I wasn't the only one who was bored...
I guess I wasn't the only one who was bored...
Oh... google just showed me another def of BOLT... The Bacon Onion Lettuce and Tomato Sandwitch (BOLT)
So if you serve a BOLT out of a food truck... are you a BOLT driver?
So if you serve a BOLT out of a food truck... are you a BOLT driver?
Yeah, but, what is the drill driving? If it’s drilling a hole, it’s a drill. If it’s driving something like a screw it’s a “screw driver”, etc. The marketing message is you’re buying a power drill, but you can use it to drive screws. But I suppose the only difference is what you insert into the drill chuck to be turned.
There are manually-powered drills common in wood-working shops but I doubt they are or were used to drive-in screws. Contemporary language usages
. It’s like saying “they” (plural) when you are referring to “he” or “she” (singulars). It’s no wonder we might not know a screw from a bolt by nomenclature.
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