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The Natural Philosopher[_2_] The Natural Philosopher[_2_] is offline
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Default Coach bolts, carriage bolts, coach screws etc.

On 27/09/17 06:51, Richard wrote:
On 26/09/2017 13:28, Dave Plowman (News) wrote:
In article ,
Â*Â*Â* Graeme wrote:
In message , Huge
writes
On 2017-09-26, Graeme wrote:


Why is a machine screw called a screw when it is a bolt?

Because it isn't a bolt.


OK.Â* I have always assumed that anything with a parallel shaft or thread
is a bolt, but anything with a tapered shaft and thread is a screw, but
apparently not.


Huge's definition is certainly the one I remember - a bolt isn't threaded
all the way. But just when a machine screw becomes just a screw I dunno.


A bolt is a screw if screwed into something rather than having a nut
attached.


No, it isn't.

A bolt is a part threaded machine screw, A machine screw is designed to
attach into a pre threaded hole, possibly in a nut. Both have constant
diameter and thread.

A Woodscrew is self cutting and so are self tappers for metal sheet and
plastic.




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