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> Couldn't the exact same fastener fit either definition depending on the context in which it's intended to be used? Nope. The two definitions are mutually exc

by 4ndr3vv 10y ago

> Couldn't the exact same fastener fit either definition depending on the context in which it's intended to be used? Nope. The two definitions are mutually exclusive, that's the point! Give me an example when a screw uses a nut. There isn't one, because when a fastener uses a nut, its a bolt! Give me an example when a bolt has a thread that produces from the shaft body. Again, there isnt one, as this would make it a screw.

ghshephard 10y ago
Can you clarify what you mean when you say, " thread that produces from the shaft body. " - I read that phrase over a few times, still not clear what you are saying.
- 4ndr3vv 10y ago
  Get a pencil, now wrap a piece of string around it. The string protrudes from the pencil "shaft body" as per a screw. Conversely in a bolt, the thread is machined into the shaft; imagine carving the line that the string made into the pencil (so that you are removing rather than adding material) to produce the thread.
  - ghshephard 10y ago
    So you are saying that if the threads are sunken below the shaft, then that suggests you have a bolt, but if the threads are above the surface of the shaft - that suggests screw? Now on a quest to find a screw with threads sunken into the shaft, defining said screw as something that is only tightened by applying pressure to the head.
    - Someone 10y ago
      https://www.boltdepot.com/Product-Details.aspx?product=1884 https://www.boltdepot.com/Product-Details.aspx?product=1884 almost is fully sunken into the shaft ("no, the shaft gets thinner" IMO is not a valid argument)
      - ghshephard 10y ago
        But that's a case where the threads are definitely external, not internal to the shaft. The threads are the skinny part, and they are raised above the shaft in the version you just sent.
        Someone 10y ago
        How do you know whether the whole shaft was equal in width to what's now closest to the head and something was cut away or whether it was smaller to start with, and something was added? Or,is your argument that this could be a screw: /\_/\_/\_/\_ \ _ _ _ _ / \/ \/ \/ \/ but this _ _ _ _ _/ \/ \/ \/ \ \ _/ \_/\_/\_/\_/ cannot be because the outside isn't sharp enough to 'bite' into the material it is screwed into? I can see the latter holding in rubbery material that tears easily.
        ghshephard 10y ago
        First, hero points for doing a text based screw description. Second, I assume that 100% of screws and bolts are created by cutting away - hard to imagine adding something to the outside of a shaft. The only question is whether the resulting threads are raised above the shaft (screw)- by cutting away the shaft, or sunken below (bolt), by leaving the shaft in place and cutting in the threads. I realize there is nuance here - which is why I"m interested in seeing if I can find a screw (or bolt) that seems to break this pattern.
Someone 10y ago
From section 3 of the PDF: "Because of basic design, it is possible to use certain types of screws in combination with a nut" Also take a look at the "Square Head Set Screw" in section 5.4 and https://en.wikipedia.org/wiki/Screw#Differentiation_between_bolt_and_screw https://en.wikipedia.org/wiki/Screw#Differentiation_between_.... [also: https://en.m.wikipedia.org/wiki/Screw#United_States_government_standards https://en.m.wikipedia.org/wiki/Screw#United_States_governme... explains why the government needs to define this: different tariffs. That page also mentions "In 1991 responding to an influx of counterfeit fasteners Congress passed PL 101-592[12] "Fastener Quality Act"". Apparently, screws/bolts got imported as bolts/screws]
mikeash 10y ago
Take a threaded fastener and insert it into a threaded hole. By the definition given here, it's a screw. Now remove it and put a nut on the end instead. By the definition given here, it's been transmuted into a bolt despite no physical changes to the item itself.
PeanutNore 10y ago
When you put a nut on a machine screw it doesn't cease to be a machine screw, but it works and I do it frequently. However, the document accounts for this in section 3: "Because of basic design, it is possible to use certain types of screws in combination with a nut. Any externally threaded fastener which has a majority of the design characteristics which assist its proper use in a tapped or other preformed hole is a screw, regardless of how it is used in its service application."

by 4ndr3vv 10y ago

ghshephard 10y ago

Can you clarify what you mean when you say, " thread that produces from the shaft body. " - I read that phrase over a few times, still not clear what you are saying.

4ndr3vv 10y ago
Get a pencil, now wrap a piece of string around it. The string protrudes from the pencil "shaft body" as per a screw. Conversely in a bolt, the thread is machined into the shaft; imagine carving the line that the string made into the pencil (so that you are removing rather than adding material) to produce the thread.
- ghshephard 10y ago
  So you are saying that if the threads are sunken below the shaft, then that suggests you have a bolt, but if the threads are above the surface of the shaft - that suggests screw? Now on a quest to find a screw with threads sunken into the shaft, defining said screw as something that is only tightened by applying pressure to the head.
  - Someone 10y ago
    https://www.boltdepot.com/Product-Details.aspx?product=1884 https://www.boltdepot.com/Product-Details.aspx?product=1884 almost is fully sunken into the shaft ("no, the shaft gets thinner" IMO is not a valid argument)
    - ghshephard 10y ago
      But that's a case where the threads are definitely external, not internal to the shaft. The threads are the skinny part, and they are raised above the shaft in the version you just sent.
      - Someone 10y ago
        How do you know whether the whole shaft was equal in width to what's now closest to the head and something was cut away or whether it was smaller to start with, and something was added? Or,is your argument that this could be a screw: /\_/\_/\_/\_ \ _ _ _ _ / \/ \/ \/ \/ but this _ _ _ _ _/ \/ \/ \/ \ \ _/ \_/\_/\_/\_/ cannot be because the outside isn't sharp enough to 'bite' into the material it is screwed into? I can see the latter holding in rubbery material that tears easily.
        ghshephard 10y ago
        First, hero points for doing a text based screw description. Second, I assume that 100% of screws and bolts are created by cutting away - hard to imagine adding something to the outside of a shaft. The only question is whether the resulting threads are raised above the shaft (screw)- by cutting away the shaft, or sunken below (bolt), by leaving the shaft in place and cutting in the threads. I realize there is nuance here - which is why I"m interested in seeing if I can find a screw (or bolt) that seems to break this pattern.

Someone 10y ago

From section 3 of the PDF: "Because of basic design, it is possible to use certain types of screws in combination with a nut" Also take a look at the "Square Head Set Screw" in section 5.4 and https://en.wikipedia.org/wiki/Screw#Differentiation_between_bolt_and_screw https://en.wikipedia.org/wiki/Screw#Differentiation_between_.... [also: https://en.m.wikipedia.org/wiki/Screw#United_States_government_standards https://en.m.wikipedia.org/wiki/Screw#United_States_governme... explains why the government needs to define this: different tariffs. That page also mentions "In 1991 responding to an influx of counterfeit fasteners Congress passed PL 101-592[12] "Fastener Quality Act"". Apparently, screws/bolts got imported as bolts/screws]

mikeash 10y ago

Take a threaded fastener and insert it into a threaded hole. By the definition given here, it's a screw. Now remove it and put a nut on the end instead. By the definition given here, it's been transmuted into a bolt despite no physical changes to the item itself.

PeanutNore 10y ago

When you put a nut on a machine screw it doesn't cease to be a machine screw, but it works and I do it frequently. However, the document accounts for this in section 3: "Because of basic design, it is possible to use certain types of screws in combination with a nut. Any externally threaded fastener which has a majority of the design characteristics which assist its proper use in a tapped or other preformed hole is a screw, regardless of how it is used in its service application."