correct name for these screws

[Andrew]

A screw have a pointed end to cut into the timber and bolt has flat end.

Set screws have a flat end.
Try googling for an M8 set screw and see what comes up.

 

[sleepy]

A screw have a pointed end to cut into the timber and bolt has flat end.

That can't be right, google set screw and see what comes up

 

[llamedos]

I would know a "set" screw as a larger "Grub" screw with a flat end for "setting"

 

[sleepy]

The difference between a bolt and a screw is that you tighten a screw by turning the head but you tighten a bolt by turning the nut.

Ie. a bolt is only a bolt if used with a nut, otherwise it is a screw.

 

[llamedos]

thunder bolt as said, has a wide open thread, and flat end not a point

 

[roscoe erf]

The difference between a bolt and a screw is that you tighten a screw by turning the head but you tighten a bolt by turning the nut.

Ie. a bolt is only a bolt if used with a nut, otherwise it is a screw.

Exactly

 

[llamedos]

set screw =

 

[sleepy]

set screw = View attachment 24181

That should really be called a stud because by definition a screw or bolt must have a head. But everyone calls it a grub screw!

 

[llamedos]

That should really be called a stud because by definition a screw or bolt must have a head. But everyone calls it a grub screw!

see earlier post

thunder bolt =

 

[sleepy]

see earlier post

thunder bolt = View attachment 24182

And this should be a thunder screw

 

[llamedos]

this is what type I want, as @Badshot linked earlier

 

[sleepy]

this is what type I want, as @Badshot linked earlier

View attachment 24183

Coach screw

But they are shite these are best

 

[Badshot]

see earlier post

thunder bolt = View attachment 24182

you beat me to it, and a turbo coach

Note the cut out at the point to cut it's own hole along with the 'cutters' in between the threads, they are a harder steel than the ordinary coach screws and have a narrower shank.

 

[llamedos]

yes it will need something with washer type collar, similar to that and also a hex head, it is to screw a batten down onto sleepers, and needs a good strong grip, and be pretty rot resistant & good extraction if necessary, so I thought the unthreaded collar before the threaded part would be best

 

[JNP]

screw
skruː/
noun
1.
a short, slender, sharp-pointed metal pin with a raised helical thread running around it.

 

[JNP]

Bolt
A fastener consisting of a threaded pin or rod with a head at one end, designed to be inserted through holes in assembled parts and secured by a mated nut that is tightened by applying torque.

 

[JP1]

Bolt
A fastener consisting of a threaded pin or rod with a head at one end, designed to be inserted through holes in assembled parts and secured by a mated nut that is tightened by applying torque.

True but what @llamedos posted is a coach bolt!!!!!

 

[Badshot]

This is what I always understood as a coach bolt. Parker's sell them as carriage bolts, so just a posher name.

 

[Paddington]

Lag screws.

 

[JNP]

True but what @llamedos posted is a coach bolt!!!!!

Thats a coach screw, as @Badshot posted, a coach bolt is the one with a nut. I buy 100's of coash bolts each week and thats what they send me

Prehaps @llamedos should fax them the picture to be sure