rick wrote in news:rmpqf5$dvk$1
@gioia.aioe.org:

I have a need to find a replacement screw
Luckily thread is nothing esoteric M4 x 8

If a Phillip head .... but the head is fairly wide ~10mm and pretty thin.

Anybody know if there is a name for this type of screw ...

https://flic.kr/p/2jXJRyz


Try "Washer Head Machine Screw"

"michael adams" wrote in message
...

"Dave Plowman (News)" wrote in message
...
In article ,
michael adams wrote:
Hmm. So why do we have nuts and bolts if a bolt describes the whole
thing?

Eh ?

Where does "a bolt" describe the whole thing.

You push the bolt through the hole and then place a nut on the end,
and then tighten the nut.

But you've said a bolt is only a bolt if it has a nut. No nut, it's not a
bolt but a machine screw.

Indeed. So if cylinder head bolts don't require nuts then they're
not bolts but screws; as I said .

As to the precise definition of machine screws as against any other
type of screw, say set screws, I have no strong opinions either way.
The generic term "screw" will suffice.

I would say the the difference between a bolt and a machine screw is much
less (both have parallel threads) than between a machine screw and a tapered
wood screw. If you want to be imprecise, calling a machine screw a bolt is
less confusing than calling it a screw which is more usually tapered.

BTW you seemed to have overlooked my rather unfortunate error in
saying that studs are threaded into cylinder heads; rather than
what I should have said, threaded into cylinder blocks.

Likewise, "wheel bolts" (for fastening car wheels onto hubs) are really
(very large) "machine screws" because they screw into threads in the hub
rather that into nuts on the reverse of non-threaded holes in the hub.

As a matter of interest, when and why did cars change from using threaded
studs fastened into the hub with the wheel fastened to the hub by nuts, to
the modern practice of using bolts (machine screws?) into threaded holes in
the hub? Was it to make it easier to fit the wheel, in that you only have to
locate the centre of the wheel onto the protruding boss on the hub and can
then rotate it until the holes line up, rather than having to locate four
(or more) holes in the wheel onto the protruding studs? My impression is
that all manufacturers seemed to change over at about the same time, some
time in the late 1970s or early 1980s, which suggests some external factor
that caused them all to change.

On 22/10/2020 14:48:57, Andrew wrote:
On 22/10/2020 08:27, michael adams wrote:
A bolt is threaded into a nut to tighten it,

A screw is threaded into a female thread, or as in the case of woodscrews
creates it own female thread.

Is a cylinder head bolt, a bolt or a machine screw ?.

In the UK it would be a bolt. In other countries it may be a screw.

This link may help to understand the USA vs UK nomenclatu
https://www.accu.co.uk/en/p/131-diff...rews-and-bolts

Interesting point about bolts and screws in that the USA had some
historical differences in taxation. Such classification will always
introduce distortions and confusions.

Another example of this kind of distortion:
https://en.wikipedia.org/wiki/Screw
"Reasonably, these fasteners might be referred to as bolts, but based on
the US government document Distinguishing Bolts from Screws, the US
government might classify them as screws because of the tighter tolerance."

Be careful as wiki is very much USA centric.

For the UK, it's simple. A bolt is a fastener with a portion left
unthreaded. A machine screw, or set screw is fully threaded.

If you ask a UK supplier for a bolt you will get a partly threaded
'bolt'. If you ask for a machine screw or anything with "screw" in its
name, it will fully threaded.

YMMV + I am sure there are exceptions! :-)

"NY" wrote in message ...

I would say the the difference between a bolt and a machine screw is much less (both
have parallel threads) than between a machine screw and a tapered wood screw. If you
want to be imprecise, calling a machine screw a bolt is less confusing than calling it
a screw which is more usually tapered.

But a machine screw like all screws, is screwed into a female thread.
Either one already existing in the case of metal screws or one made
in the course or operation in the case of wood.
Thats why they're called screws because they have to be screwed in.
Whereas a bolt is simply inserted into the hole. And it's the nut
that has to be screwed onto the threaded end of the bolt.



BTW you seemed to have overlooked my rather unfortunate error in
saying that studs are threaded into cylinder heads; rather than
what I should have said, threaded into cylinder blocks.

Likewise, "wheel bolts" (for fastening car wheels onto hubs) are really (very large)
"machine screws" because they screw into threads in the hub rather that into nuts on
the reverse of non-threaded holes in the hub.

As a matter of interest, when and why did cars change from using threaded studs
fastened into the hub with the wheel fastened to the hub by nuts, to the modern
practice of using bolts (machine screws?) into threaded holes in the hub?

No they're definitely screws, of some kind or other if they have to be
screwed in. Maybe calling them all "bolts" as with cylinder head "bolts"
is some kind of affectation among car mechanics.

Or maybe all screws over a certain diameter are referred to as "bolts"
regardless. I would be more than willing to defer to any reputable
source claiming that this was indeed the case.

All My Oxford Dictionary source says on the subject is
3 A stout pin for fastening; a door-fastening comprising a sliding bar and
a socket on a jamb, lintel, or threshold; a metal pin with a head for holding
things together, usu. secured with a nut or riveted. ME.

So no reference to size, but a "usu."



Was it to make it easier to fit the wheel, in that you only have to locate the centre
of the wheel onto the protruding boss on the hub and can then rotate it until the holes
line up, rather than having to locate four (or more) holes in the wheel onto the
protruding studs? My impression is that all manufacturers seemed to change over at
about the same time, some time in the late 1970s or early 1980s, which suggests some
external factor that caused them all to change.



michael adams

....

On 22/10/2020 17:25, michael adams wrote:
"NY" wrote in message ...

I would say the the difference between a bolt and a machine screw is much less (both
have parallel threads) than between a machine screw and a tapered wood screw. If you
want to be imprecise, calling a machine screw a bolt is less confusing than calling it
a screw which is more usually tapered.

But a machine screw like all screws, is screwed into a female thread.
Either one already existing in the case of metal screws or one made
in the course or operation in the case of wood.
Thats why they're called screws because they have to be screwed in.
Whereas a bolt is simply inserted into the hole. And it's the nut
that has to be screwed onto the threaded end of the bolt.



BTW you seemed to have overlooked my rather unfortunate error in
saying that studs are threaded into cylinder heads; rather than
what I should have said, threaded into cylinder blocks.

Likewise, "wheel bolts" (for fastening car wheels onto hubs) are really (very large)
"machine screws" because they screw into threads in the hub rather that into nuts on
the reverse of non-threaded holes in the hub.

As a matter of interest, when and why did cars change from using threaded studs
fastened into the hub with the wheel fastened to the hub by nuts, to the modern
practice of using bolts (machine screws?) into threaded holes in the hub?

No they're definitely screws, of some kind or other if they have to be
screwed in. Maybe calling them all "bolts" as with cylinder head "bolts"
is some kind of affectation among car mechanics.

Or maybe all screws over a certain diameter are referred to as "bolts"
regardless. I would be more than willing to defer to any reputable
source claiming that this was indeed the case.

All My Oxford Dictionary source says on the subject is
3 A stout pin for fastening; a door-fastening comprising a sliding bar and
a socket on a jamb, lintel, or threshold; a metal pin with a head for holding
things together, usu. secured with a nut or riveted. ME.

So no reference to size, but a "usu."



Was it to make it easier to fit the wheel, in that you only have to locate the centre
of the wheel onto the protruding boss on the hub and can then rotate it until the holes
line up, rather than having to locate four (or more) holes in the wheel onto the
protruding studs? My impression is that all manufacturers seemed to change over at
about the same time, some time in the late 1970s or early 1980s, which suggests some
external factor that caused them all to change.



michael adams

...






My astra wheel nuts /bolts are not screws.

"Andrew" wrote in message
...

On 22/10/2020 17:25, michael adams wrote:

"NY" wrote in message ...


As a matter of interest, when and why did cars change from using threaded studs
fastened into the hub with the wheel fastened to the hub by nuts, to the modern
practice of using bolts (machine screws?) into threaded holes in the hub?


No they're definitely screws, of some kind or other if they have to be
screwed in. Maybe calling them all "bolts" as with cylinder head "bolts"
is some kind of affectation among car mechanics.


My astra wheel nuts /bolts are not screws.

If you've got nuts, then they're bolts obviously.

That's the definition of a bolt; something with a thread on the end onto which is
screwed a nut.

The OP is talking about screws which you screw into the hub with no nuts involved.


michael adams

....

"Fredxx" wrote in message ...

Yes, a bolt has a plain shank, sometimes used for location and a machine screw is fully
threaded, aprt from say the top 1mm or so.

So you're saying that standard pattern woodscrews, all of which have a plain shank
are actually bolts then ?

" ?

You are now saying a cylinder head bolt is a screw because retention is not by a nut.
This is in the face of centuries of UK tradition.

As on the cylinder heads as found on the engines of Mail Coaches and similar
you mean ?


There is usually a very strong correlation between the hole size and bolt/screw.
Anything else would be considered a bodge.

But at least it *is* possible bodge with genuine bolts whereas it clearly isn't with
the
kind of nuts which you insist on calling bolts based solely on their appearance.

I think you're getting confused with nuts and bolts. I have never called a nut a bolt
or visa-versa.

You probably have at some time or another but I'll let that one go for now,

So yes, go on, do your lap of honour.


michael adams

....

I called it a screw as it is fully threaded not part threaded like a bolt.
There is no taper or shoulder


On 21/10/2020 18:19, Andrew wrote:
On 21/10/2020 18:17, rick wrote:
I have a need to find a replacement screw
Luckily thread is nothing esotericÂ*Â* M4 x 8

If a Phillip head .... but the head is fairly wide ~10mm and pretty thin.

Anybody know if there is a name for this type of screwÂ* ...

https://flic.kr/p/2jXJRyz

I would call that a bolt of some sort, rather than a screw.
Does it taper at all at the 'sharp' end ?. Difficult to say
from the pic.

On 21/10/2020 18:59, soup wrote:
On 21/10/2020 18:17, rick wrote:
I have a need to find a replacement screw
Luckily thread is nothing esotericÂ*Â* M4 x 8

If a Phillip head .... but the head is fairly wide ~10mm and pretty thin.

Anybody know if there is a name for this type of screwÂ* ...

https://flic.kr/p/2jXJRyz

Â*Wafer head.




Well a new one on me ... never heard of wafer head screws .... but that
is what it looks like .... Thnx

Now have to find one.

On 21/10/2020 23:19, John Rumm wrote:
On 21/10/2020 18:17, rick wrote:
I have a need to find a replacement screw
Luckily thread is nothing esotericÂ*Â* M4 x 8

If a Phillip head .... but the head is fairly wide ~10mm and pretty thin.

Anybody know if there is a name for this type of screwÂ* ...

https://flic.kr/p/2jXJRyz

try "pan head".



too thick ....... My solution (it seems) is a "flanged button head screw."

On 22/10/2020 09:52, polygonum_on_google wrote:
On Wednesday, 21 October 2020 18:17:32 UTC+1, rick wrote:
I have a need to find a replacement screw
Luckily thread is nothing esoteric M4 x 8

If a Phillip head .... but the head is fairly wide ~10mm and pretty thin.

Anybody know if there is a name for this type of screw ...

https://flic.kr/p/2jXJRyz

This link takes you to numerous forms of pan head screw:

https://www.accu.co.uk/en/161-pan-head-screws

Good, clear pictures.

It is not a Pan Head (or cheese head screw)

On 22/10/2020 14:47, Andrew wrote:


I have plenty of hexagon-headed bolts where the thread
goes right uup to the head though.

Then that would be a Hex head machine screw, not a bolt.

On 22/10/2020 18:15, rick wrote:
On 21/10/2020 18:59, soup wrote:
On 21/10/2020 18:17, rick wrote:
I have a need to find a replacement screw
Luckily thread is nothing esotericÂ*Â* M4 x 8

If a Phillip head .... but the head is fairly wide ~10mm and pretty
thin.

Anybody know if there is a name for this type of screwÂ* ...

https://flic.kr/p/2jXJRyz

Â*Â*Wafer head.

Well a new one on me ... never heard of wafer head screws .... but that
is what it looks like .... Thnx

Now have to find one.

ebay?

https://www.ebay.co.uk/itm/Phillips-...-/123332995002

Alibaba (if you know how to work it, I don't. Suspect it is more for
distributors who deal in thousands).

https://www.alibaba.com/product-deta...500424694.html

Mm they call 'them' machine screw bolts. Whither bolt/machine screw
definitions now?

"soup" wrote in message
...

Mm they call 'them' machine screw bolts. Whither bolt/machine screw definitions now?

You can use a machine screw as a bolt providing it goes right through and you
can thread a nut on the end and tighten it that way. Depending on how oversize
you make the hole you can either thread the screw through the hole or push it
through, like any other bolt.

michael adams

....

On 22/10/2020 17:51:28, michael adams wrote:
"Fredxx" wrote in message ...

Yes, a bolt has a plain shank, sometimes used for location and a machine screw is fully
threaded, aprt from say the top 1mm or so.

So you're saying that standard pattern woodscrews, all of which have a plain shank
are actually bolts then ?

" ?

Different trade where different terms are used. Sheesh.


You are now saying a cylinder head bolt is a screw because retention is not by a nut.
This is in the face of centuries of UK tradition.

As on the cylinder heads as found on the engines of Mail Coaches and similar
you mean ?

The last mail coach I saw ran on rails. You're now being ridiculous.

There is usually a very strong correlation between the hole size and bolt/screw.
Anything else would be considered a bodge.

But at least it *is* possible bodge with genuine bolts whereas it clearly isn't with
the
kind of nuts which you insist on calling bolts based solely on their appearance.

I think you're getting confused with nuts and bolts. I have never called a nut a bolt
or visa-versa.

You probably have at some time or another but I'll let that one go for now,

So yes, go on, do your lap of honour.

I don't feel any need. I just don't see your point.

On 22/10/2020 14:47, Andrew wrote:

I have plenty of hexagon-headed bolts where the thread
goes right uup to the head though.

They aren't bolts, they are machine screws.

Bill

"Fredxx" wrote in message ...
On 22/10/2020 17:51:28, michael adams wrote:
"Fredxx" wrote in message ...

Yes, a bolt has a plain shank, sometimes used for location and a machine screw is
fully
threaded, aprt from say the top 1mm or so.

So you're saying that standard pattern woodscrews, all of which have a plain shank
are actually bolts then ?

" ?

Different trade where different terms are used. Sheesh.

Both coach bolts and coach screws have a plain shank and both are used in the one trade.

Which was coachbuilding presumably, in the first instance..



You are now saying a cylinder head bolt is a screw because retention is not by a nut.
This is in the face of centuries of UK tradition.

As on the cylinder heads as found on the engines of Mail Coaches and similar
you mean ?

The last mail coach I saw ran on rails. You're now being ridiculous.

Trains don't have cylinder heads. I'm just wondering where these bolts were
to be found centuries ago. Obviously if they'd been on Mail Coaches they'd have
been coach bolts, but then they might also have used coach screws on Mail
Coaches as well.



There is usually a very strong correlation between the hole size and bolt/screw.
Anything else would be considered a bodge.

But at least it *is* possible bodge with genuine bolts whereas it clearly isn't with
the
kind of nuts which you insist on calling bolts based solely on their appearance.

I think you're getting confused with nuts and bolts. I have never called a nut a bolt
or visa-versa.

You probably have at some time or another but I'll let that one go for now,

So yes, go on, do your lap of honour.

I don't feel any need. I just don't see your point.

With a bolt Its possible use a slightly smaller diameter providing the head and nut are
large enough; whereas with a screw, the thread needs to exactly match that
of the hole.


michael adams

....

On 22 Oct 2020 at 17:42:21 BST, ""michael adams""
wrote:


"Andrew" wrote in message
...

On 22/10/2020 17:25, michael adams wrote:

"NY" wrote in message
...


As a matter of interest, when and why did cars change from using threaded
studs
fastened into the hub with the wheel fastened to the hub by nuts, to the
modern
practice of using bolts (machine screws?) into threaded holes in the hub?


No they're definitely screws, of some kind or other if they have to be
screwed in. Maybe calling them all "bolts" as with cylinder head "bolts"
is some kind of affectation among car mechanics.


My astra wheel nuts /bolts are not screws.

If you've got nuts, then they're bolts obviously.

That's the definition of a bolt; something with a thread on the end onto
which is
screwed a nut.

The OP is talking about screws which you screw into the hub with no nuts
involved.


michael adams

...

I defer to your greater knowledge, of course, but I have never heard studs
called bolts. In fact, the humble stud contains in its person both what you
call a screw and what you call a bolt. So best to call them studs?
--
Roger Hayter

On 22 Oct 2020 at 16:17:18 BST, "JohnP" wrote:

rick wrote in news:rmpqf5$dvk$1
@gioia.aioe.org:

I have a need to find a replacement screw
Luckily thread is nothing esoteric M4 x 8

If a Phillip head .... but the head is fairly wide ~10mm and pretty thin.

Anybody know if there is a name for this type of screw ...

https://flic.kr/p/2jXJRyz


Try "Washer Head Machine Screw"

I'd just add that most common M4 screws have a 0.7mm pitch, and this one looks
to me quite coarse. But 0.5mm (and possibly other pitches) also exist. So
I'd check it, if not with a thread gauge at least with an M4 nut which if
general purpose will probably be 0.7mm.


--
Roger Hayter

On 22/10/2020 22:28:44, michael adams wrote:
"Fredxx" wrote in message ...
On 22/10/2020 17:51:28, michael adams wrote:
"Fredxx" wrote in message ...

Yes, a bolt has a plain shank, sometimes used for location and a machine screw is
fully
threaded, aprt from say the top 1mm or so.

So you're saying that standard pattern woodscrews, all of which have a plain shank
are actually bolts then ?

" ?

Different trade where different terms are used. Sheesh.

Both coach bolts and coach screws have a plain shank and both are used in the one trade.

Which was coachbuilding presumably, in the first instance..

Ok. Woodworking techniques were also used in steel/iron structure. If
you look at the bridge at Ironbridge you'll see all manner of
woodworking techniques that are of course now obsolete.

You are now saying a cylinder head bolt is a screw because retention is not by a nut.
This is in the face of centuries of UK tradition.

As on the cylinder heads as found on the engines of Mail Coaches and similar
you mean ?

The last mail coach I saw ran on rails. You're now being ridiculous.

Trains don't have cylinder heads. I'm just wondering where these bolts were
to be found centuries ago. Obviously if they'd been on Mail Coaches they'd have
been coach bolts, but then they might also have used coach screws on Mail
Coaches as well.

Some do, mainly diesels and not sure how Deltics are configured.

There is usually a very strong correlation between the hole size and bolt/screw.
Anything else would be considered a bodge.

But at least it *is* possible bodge with genuine bolts whereas it clearly isn't with
the
kind of nuts which you insist on calling bolts based solely on their appearance.

I think you're getting confused with nuts and bolts. I have never called a nut a bolt
or visa-versa.

You probably have at some time or another but I'll let that one go for now,

So yes, go on, do your lap of honour.

I don't feel any need. I just don't see your point.

With a bolt Its possible use a slightly smaller diameter providing the head and nut are
large enough; whereas with a screw, the thread needs to exactly match that
of the hole.

There is a rule of thumb that a thread should penetrate 1.5 x major
diameter. Everything has a tolerance.

The US has difference tolerance for screws and bolts.

The ISO/BS standard doesn't distinguish between bolts and screws and
just mentions "screw threads" or "coarse threads" and their tolerance.
It even has "screws" and "nuts" in the same table.

"Roger Hayter" wrote in message
...
On 22 Oct 2020 at 17:42:21 BST, ""michael adams""
wrote:


"Andrew" wrote in message
...

On 22/10/2020 17:25, michael adams wrote:

"NY" wrote in message
...


As a matter of interest, when and why did cars change from using threaded
studs
fastened into the hub with the wheel fastened to the hub by nuts, to the
modern
practice of using bolts (machine screws?) into threaded holes in the hub?


No they're definitely screws, of some kind or other if they have to be
screwed in. Maybe calling them all "bolts" as with cylinder head "bolts"
is some kind of affectation among car mechanics.


My astra wheel nuts /bolts are not screws.

If you've got nuts, then they're bolts obviously.

That's the definition of a bolt; something with a thread on the end onto
which is
screwed a nut.

The OP is talking about screws which you screw into the hub with no nuts
involved.


michael adams

...

I defer to your greater knowledge, of course, but I have never heard studs
called bolts. In fact, the humble stud contains in its person both what you
call a screw and what you call a bolt. So best to call them studs?


It was Andrew who called them bolts not me. As in " My astra wheel
nuts /bolts are not screws".

This was in response to the OP who was talking about machine screws which are
screwed into threaded holes in the hub, with no nuts involved.

Formerly, as the OP explained the wheel was fastened with nuts threaded onto
the end of studs as in "As a matter of interest, when and why did cars change
from using threaded studs". But neither the OP nor myself ever referred to
those studs as bolts

Presumably this was what Andrew was referring to only he chose to call them
bolts. And for all I know bolts may in fact have been used on Astras
in that situation for some particular reason. Which Andrew having a
greater knowledge of Astras than myself, will of course be in a better
position to answer.


michael adams

....

On 23/10/2020 00:05:22, Roger Hayter wrote:
On 22 Oct 2020 at 16:17:18 BST, "JohnP" wrote:

rick wrote in news:rmpqf5$dvk$1
@gioia.aioe.org:

I have a need to find a replacement screw
Luckily thread is nothing esoteric M4 x 8

If a Phillip head .... but the head is fairly wide ~10mm and pretty thin.

Anybody know if there is a name for this type of screw ...

https://flic.kr/p/2jXJRyz


Try "Washer Head Machine Screw"

I'd just add that most common M4 screws have a 0.7mm pitch, and this one looks
to me quite coarse. But 0.5mm (and possibly other pitches) also exist. So
I'd check it, if not with a thread gauge at least with an M4 nut which if
general purpose will probably be 0.7mm.

Could be UNC? #8 has a major of 4.16mm and a pitch of 0.8mm

An M4 thread by default will have a pitch of 0.7mm. If a fine pitch is
specified then 0.5mm is the standard.
https://en.wikipedia.org/wiki/ISO_metric_screw_thread

It's useful to note that if the pitch is not specified then the thread
should be the standard (coarse) pitch, ie:
M4 - will have a 0.7mm pitch
M4 x 0.5 - fine pitch 0.5mm as defined.

On 22/10/2020 23:56, Roger Hayter wrote:
On 22 Oct 2020 at 17:42:21 BST, ""michael adams""
wrote:


"Andrew" wrote in message
...

On 22/10/2020 17:25, michael adams wrote:

"NY" wrote in message
...


As a matter of interest, when and why did cars change from using threaded
studs
fastened into the hub with the wheel fastened to the hub by nuts, to the
modern
practice of using bolts (machine screws?) into threaded holes in the hub?


No they're definitely screws, of some kind or other if they have to be
screwed in. Maybe calling them all "bolts" as with cylinder head "bolts"
is some kind of affectation among car mechanics.


My astra wheel nuts /bolts are not screws.

If you've got nuts, then they're bolts obviously.

That's the definition of a bolt; something with a thread on the end onto
which is
screwed a nut.

The OP is talking about screws which you screw into the hub with no nuts
involved.


michael adams

...

I defer to your greater knowledge, of course, but I have never heard studs
called bolts. In fact, the humble stud contains in its person both what you
call a screw and what you call a bolt. So best to call them studs?

Michael adams is a pompous ignorant prick. Ignore.

Bolts are threaded rod with a head and a plain shaft part as well as a
threaded part. End of.

Screws have a head and are all threaded.

Studs have a thread but no head.

Nuts are irrelevant to the above definitions


--
How fortunate for governments that the people they administer don't think.

Adolf Hitler

"Fredxx" wrote in message ...
On 22/10/2020 22:28:44, michael adams wrote:
"Fredxx" wrote in message ...
On 22/10/2020 17:51:28, michael adams wrote:
"Fredxx" wrote in message ...

Yes, a bolt has a plain shank, sometimes used for location and a machine screw is
fully
threaded, aprt from say the top 1mm or so.

So you're saying that standard pattern woodscrews, all of which have a plain shank
are actually bolts then ?

" ?

Different trade where different terms are used. Sheesh.

Both coach bolts and coach screws have a plain shank and both are used in the one
trade.

Which was coachbuilding presumably, in the first instance..

Ok. Woodworking techniques were also used in steel/iron structure. If you look at the
bridge at Ironbridge you'll see all manner of woodworking techniques that are of course
now obsolete.

But both coach bolts and coach screws have a plain shank at the head end ;
which so it was claimed was the distinguishing feature as between screws
(no) and bolts (yes).

By woodworking techniques I assume you mean joints. Entirely from memory
and without looking it up might you be referring to pegged tenons among
other joints ? As far from being obsolete such joints are an obvious
manifestation of sound mechanical principles in a way that more modern
fittings are not, being hidden away from sight. I also seem to remember that
pegged tenons and similar were a feature of the knock down furniture
which was popular a few decades ago, and maybe still is, in woodworking
projects.

You are now saying a cylinder head bolt is a screw because retention is not by a
nut.
This is in the face of centuries of UK tradition.

As on the cylinder heads as found on the engines of Mail Coaches and similar
you mean ?

The last mail coach I saw ran on rails. You're now being ridiculous.

Trains don't have cylinder heads. I'm just wondering where these bolts were
to be found centuries ago. Obviously if they'd been on Mail Coaches they'd have
been coach bolts, but then they might also have used coach screws on Mail
Coaches as well.

Some do, mainly diesels and not sure how Deltics are configured.

So "This is in the face of centuries of UK tradition" in building diesel
locomotives is it ?

..To repeat - "centuries of tradition". Your phrase, not mine.



There is usually a very strong correlation between the hole size and bolt/screw.
Anything else would be considered a bodge.

But at least it *is* possible bodge with genuine bolts whereas it clearly isn't
with
the
kind of nuts which you insist on calling bolts based solely on their appearance.

I think you're getting confused with nuts and bolts. I have never called a nut a
bolt
or visa-versa.

You probably have at some time or another but I'll let that one go for now,

So yes, go on, do your lap of honour.

I don't feel any need. I just don't see your point.

With a bolt Its possible use a slightly smaller diameter providing the head and nut
are
large enough; whereas with a screw, the thread needs to exactly match that
of the hole.

There is a rule of thumb that a thread should penetrate 1.5 x major diameter.
Everything has a tolerance.

The US has difference tolerance for screws and bolts.

That raises an interesting point actually. Nuts and bolts are an off the
shelf item made in standard sizes which can be expected to fit. They're
one of the first large scale manifestations of interchangeable parts.
The same could be said of screws bought off the shelf which can reasonably
expected to fit the appropriate sized nut (when they'd be functioning as bolts)
The threaded holes in components into which such screws would be
threaded on the other hand are not in themselves standard off the shelf parts,
although the actual components might be. Such holes are only tapped as and
when required.
This might mean that different standards might well apply, not necessarily
to screws and bolts which are off the shelf items, but to the threads of
nuts which are again off the shelf items, and the threads of threaded holes
in components designed to accommodate screws which are not.
Although I can't quite decide which way it should be.i.e which should be
stricter


The ISO/BS standard doesn't distinguish between bolts and screws and just mentions
"screw threads" or "coarse threads" and their tolerance. It even has "screws" and
"nuts" in the same table.

Match the hole within agreed tolerances then. Picky.



michael adams

....

"The Natural Philosopher" wrote in message
...
On 22/10/2020 23:56, Roger Hayter wrote:
On 22 Oct 2020 at 17:42:21 BST, ""michael adams""
wrote:


"Andrew" wrote in message
...

On 22/10/2020 17:25, michael adams wrote:

"NY" wrote in message
...


As a matter of interest, when and why did cars change from using threaded
studs
fastened into the hub with the wheel fastened to the hub by nuts, to the
modern
practice of using bolts (machine screws?) into threaded holes in the hub?


No they're definitely screws, of some kind or other if they have to be
screwed in. Maybe calling them all "bolts" as with cylinder head "bolts"
is some kind of affectation among car mechanics.


My astra wheel nuts /bolts are not screws.

If you've got nuts, then they're bolts obviously.

That's the definition of a bolt; something with a thread on the end onto
which is
screwed a nut.

The OP is talking about screws which you screw into the hub with no nuts
involved.


michael adams

...

I defer to your greater knowledge, of course, but I have never heard studs
called bolts. In fact, the humble stud contains in its person both what you
call a screw and what you call a bolt. So best to call them studs?

Michael adams is a pompous ignorant prick. Ignore.

Bolts are threaded rod with a head and a plain shaft part as well as a threaded part.
End of.

Screws have a head and are all threaded.

So that coach screws are actually coach bolts. I see.

As to studs, I'd already pointed out that "head nuts", are threaded onto "studs" as
compared to "head bolts" (which actually function as screws) which are screwed into
the block at 15.22 yesterday in this very thread

quote

"michael adams" wrote in message
...

[of head bolts]

Functionally its a screw, as its screwed into a thread; rather than being
secured with a nut as is a bolt.

The fact that people mistakenly refer to them as "bolts" based solely on
their appearance rather than on their function is unfortunate.

Whereas cylinder head "studs", which are first screwed into the block
then do then function as "bolts"; as they don't move any further, and are
secured by cylinder head nuts.

As with your new best friend Roger, it might actually help if you bothered to read
the thread before letting your evident bitterness and resentment get the better
of you.


michael adams

.....

In article ,
NY wrote:
What *is* the correct distinction between a bolt (which is intended to be
screwed into a nut, sandwiching something between bolt head and nut)) and a
machine screw which is designed to be screwed into a larger frame? I presume
both a bolt and a machine screw of a given diameter and thread pitch can be
used interchangeably in either role.

Generally, a bolt (with a portion not threaded so larger) helps locate the
part better than a screw threaded over its entire length. Which of course
may or may not matter. I've a feeling a bolt with that shoulder is also
stronger than one threaded over its entire length, made of the same steel.

--
* I like you. You remind me of when I was young and stupid

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
NY wrote:
As a matter of interest, when and why did cars change from using
threaded studs fastened into the hub with the wheel fastened to the hub
by nuts, to the modern practice of using bolts (machine screws?) into
threaded holes in the hub? Was it to make it easier to fit the wheel,
in that you only have to locate the centre of the wheel onto the
protruding boss on the hub and can then rotate it until the holes line
up, rather than having to locate four (or more) holes in the wheel onto
the protruding studs? My impression is that all manufacturers seemed to
change over at about the same time, some time in the late 1970s or
early 1980s, which suggests some external factor that caused them all
to change.

Interesting point. Fitting a wheel which uses bolts rather than studs is
no easier in practice IMHO. My last car which used bolts had a tool
supplied - a bolt with no head which you fitted to align the wheel when
changing.

--
*What do you call a dinosaur with an extensive vocabulary? A thesaurus.*

Dave Plowman London SW
To e-mail, change noise into sound.

On Wednesday, October 21, 2020 at 6:55:58 PM UTC+1, soup wrote:
On 21/10/2020 18:19, Andrew wrote:
On 21/10/2020 18:17, rick wrote:
I have a need to find a replacement screw
Luckily thread is nothing esotericÂ*Â* M4 x 8

If a Phillip head .... but the head is fairly wide ~10mm and pretty thin.

Anybody know if there is a name for this type of screwÂ* ...

https://flic.kr/p/2jXJRyz

I would call that a bolt of some sort, rather than a screw.
Does it taper at all at the 'sharp' end ?. Difficult to say
from the pic.

Machine screw.
But then much like the difference between a ship and a
boat, I don't think it has ever been detailed when a machine screw
becomes a bolt.

As Lord Mountbatten told his mother.'You can put a boat on a ship but not a ship on a boat"

On 23/10/2020 08:13:19, michael adams wrote:
"Fredxx" wrote in message ...
On 22/10/2020 22:28:44, michael adams wrote:
"Fredxx" wrote in message ...
On 22/10/2020 17:51:28, michael adams wrote:
"Fredxx" wrote in message ...

Yes, a bolt has a plain shank, sometimes used for location and a machine screw is
fully
threaded, aprt from say the top 1mm or so.

So you're saying that standard pattern woodscrews, all of which have a plain shank
are actually bolts then ?

" ?

Different trade where different terms are used. Sheesh.

Both coach bolts and coach screws have a plain shank and both are used in the one
trade.

Which was coachbuilding presumably, in the first instance..

Ok. Woodworking techniques were also used in steel/iron structure. If you look at the
bridge at Ironbridge you'll see all manner of woodworking techniques that are of course
now obsolete.

But both coach bolts and coach screws have a plain shank at the head end ;
which so it was claimed was the distinguishing feature as between screws
(no) and bolts (yes).

By woodworking techniques I assume you mean joints. Entirely from memory
and without looking it up might you be referring to pegged tenons among
other joints ? As far from being obsolete such joints are an obvious
manifestation of sound mechanical principles in a way that more modern
fittings are not, being hidden away from sight. I also seem to remember that
pegged tenons and similar were a feature of the knock down furniture
which was popular a few decades ago, and maybe still is, in woodworking
projects.

You are now saying a cylinder head bolt is a screw because retention is not by a
nut.
This is in the face of centuries of UK tradition.

As on the cylinder heads as found on the engines of Mail Coaches and similar
you mean ?

The last mail coach I saw ran on rails. You're now being ridiculous.

Trains don't have cylinder heads. I'm just wondering where these bolts were
to be found centuries ago. Obviously if they'd been on Mail Coaches they'd have
been coach bolts, but then they might also have used coach screws on Mail
Coaches as well.

Some do, mainly diesels and not sure how Deltics are configured.

So "This is in the face of centuries of UK tradition" in building diesel
locomotives is it ?

.To repeat - "centuries of tradition". Your phrase, not mine.

I don't recall using the words and phrases of diesels and centuries of
tradition in the same sentence. You're being disingenuous.

There is usually a very strong correlation between the hole size and bolt/screw.
Anything else would be considered a bodge.

But at least it *is* possible bodge with genuine bolts whereas it clearly isn't
with
the
kind of nuts which you insist on calling bolts based solely on their appearance.

I think you're getting confused with nuts and bolts. I have never called a nut a
bolt
or visa-versa.

You probably have at some time or another but I'll let that one go for now,

So yes, go on, do your lap of honour.

I don't feel any need. I just don't see your point.

With a bolt Its possible use a slightly smaller diameter providing the head and nut
are
large enough; whereas with a screw, the thread needs to exactly match that
of the hole.

There is a rule of thumb that a thread should penetrate 1.5 x major diameter.
Everything has a tolerance.

The US has difference tolerance for screws and bolts.

That raises an interesting point actually. Nuts and bolts are an off the
shelf item made in standard sizes which can be expected to fit. They're
one of the first large scale manifestations of interchangeable parts.
The same could be said of screws bought off the shelf which can reasonably
expected to fit the appropriate sized nut (when they'd be functioning as bolts)
The threaded holes in components into which such screws would be
threaded on the other hand are not in themselves standard off the shelf parts,
although the actual components might be. Such holes are only tapped as and
when required.
This might mean that different standards might well apply, not necessarily
to screws and bolts which are off the shelf items, but to the threads of
nuts which are again off the shelf items, and the threads of threaded holes
in components designed to accommodate screws which are not.
Although I can't quite decide which way it should be.i.e which should be
stricter


The ISO/BS standard doesn't distinguish between bolts and screws and just mentions
"screw threads" or "coarse threads" and their tolerance. It even has "screws" and
"nuts" in the same table.

Match the hole within agreed tolerances then. Picky.



michael adams

...

On 23/10/2020 08:32:03, michael adams wrote:
"The Natural Philosopher" wrote in message
...
On 22/10/2020 23:56, Roger Hayter wrote:
On 22 Oct 2020 at 17:42:21 BST, ""michael adams""
wrote:


"Andrew" wrote in message
...

On 22/10/2020 17:25, michael adams wrote:

"NY" wrote in message
...


As a matter of interest, when and why did cars change from using threaded
studs
fastened into the hub with the wheel fastened to the hub by nuts, to the
modern
practice of using bolts (machine screws?) into threaded holes in the hub?


No they're definitely screws, of some kind or other if they have to be
screwed in. Maybe calling them all "bolts" as with cylinder head "bolts"
is some kind of affectation among car mechanics.


My astra wheel nuts /bolts are not screws.

If you've got nuts, then they're bolts obviously.

That's the definition of a bolt; something with a thread on the end onto
which is
screwed a nut.

The OP is talking about screws which you screw into the hub with no nuts
involved.


michael adams

...

I defer to your greater knowledge, of course, but I have never heard studs
called bolts. In fact, the humble stud contains in its person both what you
call a screw and what you call a bolt. So best to call them studs?

Michael adams is a pompous ignorant prick. Ignore.

Bolts are threaded rod with a head and a plain shaft part as well as a threaded part.
End of.

Screws have a head and are all threaded.

So that coach screws are actually coach bolts. I see.

Different area of interest.

I don't understand why you persist.
https://www.leytonfasteners.co.uk/bo...w-information/

Common UK parlance for a bolt and a set screw is that there is thread
the entire length of the set screw, whereas a bolt is only partly threaded.

Anything else is contrary to UK convention, for decades, perhaps rather
than centuries.

You are of course perfectly free to believe otherwise, but is a foolish
approach and most unhelpful in making purchases in the UK of, or
specifying in the UK, machine/set screws / bolts.

"Fredxx" wrote in message
...

Common UK parlance for a bolt and a set screw is that there is thread the
entire length of the set screw, whereas a bolt is only partly threaded.

Anything else is contrary to UK convention, for decades, perhaps rather
than centuries.

You are of course perfectly free to believe otherwise, but is a foolish
approach and most unhelpful in making purchases in the UK of, or
specifying in the UK, machine/set screws / bolts.

So the bolts (and corresponding nuts) that I bought the other day were not
really bolts but screws because they are threaded right up to the head.

I imagine that the nature of the head is also a factor in the screw/bolt
decision. If it has round head with a flat or cross-head notch, tightened
with a screwdriver, it's a screw; if it has a hexagonal or square head, it
may be a bolt depending on how far up the shank the threads continue.

There is a third category - the ******* bolt from hell! The spare wheel on
my Peugeot 306 was held into a cage under the boot by a bolt-sized screw
with a *round* head that had a semi-cylindrical notch in it (ie the sides
were not vertical). You were supposed to use the flattened end of the
wheelbrace as a crude screwdriver. This idea failed fairly spectacularly if
the captive nut on the cage got seized onto the threads (it was exposed to
all the water that was thrown on the underside of the car), because the
curved sides of the notch in the screw head meant that the "screwdriver" end
of the wheelbrace just climbed out of the notch. It took an RAC man about
half an hour to free the seized thread with WD40, heat, lots of cursing and
imprecations about the parentage of the person who had designed it. How much
more effort does it take to cut (or die-stamp) a semi-cylindrical notch than
to cut one with vertical sides using a milling machine? Or to mill/die-stamp
a proper hexagonal head the same size as the wheel bolts.

On 23/10/2020 13:59:02, NY wrote:
"Fredxx" wrote in message
...

Common UK parlance for a bolt and a set screw is that there is thread
the entire length of the set screw, whereas a bolt is only partly
threaded.

Anything else is contrary to UK convention, for decades, perhaps
rather than centuries.

You are of course perfectly free to believe otherwise, but is a
foolish approach and most unhelpful in making purchases in the UK of,
or specifying in the UK,Â* machine/set screws / bolts.

So the bolts (and corresponding nuts) that I bought the other day were
not really bolts but screws because they are threaded right up to the head.

Very generally speaking yes. Mr Adams was probably correct in respect of
coach screws and bolts which are more associated with working in
materials other than metals.

I imagine that the nature of the head is also a factor in the screw/bolt
decision. If it has round head with a flat or cross-head notch,
tightened with a screwdriver, it's a screw; if it has a hexagonal or
square head, it may be a bolt depending on how far up the shank the
threads continue.

There is a third category - the ******* bolt from hell! The spare wheel
on my Peugeot 306 was held into a cage under the boot by a bolt-sized
screw with a *round* head that had a semi-cylindrical notch in it (ie
the sides were not vertical). You were supposed to use the flattened end
of the wheelbrace as a crude screwdriver. This idea failed fairly
spectacularly if the captive nut on the cage got seized onto the threads
(it was exposed to all the water that was thrown on the underside of the
car), because the curved sides of the notch in the screw head meant that
the "screwdriver" end of the wheelbrace just climbed out of the notch.
It took an RAC man about half an hour to free the seized thread with
WD40, heat, lots of cursing and imprecations about the parentage of the
person who had designed it. How much more effort does it take to cut (or
die-stamp) a semi-cylindrical notch than to cut one with vertical sides
using a milling machine? Or to mill/die-stamp a proper hexagonal head
the same size as the wheel bolts.

It does seem silly. A non-standard bolt/screw would have cost more than
an off-the-shelf one, even for Peugeot.

I trust you're going to replace it with a standard stainless steel variant?

"Fredxx" wrote in message
...

It does seem silly. A non-standard bolt/screw would have cost more than an
off-the-shelf one, even for Peugeot.

I trust you're going to replace it with a standard stainless steel
variant?

I would if I still had the car, but I sold it a few years ago. Until then, I
made sure that I kept the exposed nut greased, and loosened/tightened it
every month to prevent it seizing. It was still a crap design - I just found
a workaround.

Finding an off-the-shelf replacement would not have been easy - the bolt was
probably about 30 cm long. Without being able to remove the captive nut
temporarily to take into a shop, it would have been difficult to make sure
that any replacement I bought had the correct diameter and pitch of thread.

My present car doesn't have the problem, because the spare wheel is in a
trough that it accessed from inside the boot - though it does mean that it's
only big enough for one of those poxy space-saver spares. Hopefully I'll
never have a puncture out of hours when I can't take the original to a
tyre-repair place and I'm not about to begin a long journey (beyond the
distance limit of the "toy" tyre). Going on past experience, almost all of
my punctures have been discovered on a Sunday evening as I'm about to start
a long journey home: the most recent one I even checked the tyre pressure
(as I do routinely) only the day before when the tyre places were still
open.

On 23/10/2020 15:15:05, NY wrote:

Snip

My present car doesn't have the problem, because the spare wheel is in a
trough that it accessed from inside the boot - though it does mean that
it's only big enough for one of those poxy space-saver spares.

It's worth checking the depth of the wheel well. Sometimes a standard
full wheel will fit.

"Fredxx" wrote in message ...

I don't understand why you persist.
https://www.leytonfasteners.co.uk/bo...w-information/

Common UK parlance for a bolt and a set screw is that there is thread the entire length
of the set screw, whereas a bolt is only partly threaded.


Clearly the "experts" at the University of Leytonfasteners along with Professor Turnip
have never heard of "roofing bolts" either.

https://www.google.co.uk/search?q=ro...w=1024&bih=642



michael adams

....

On 23/10/2020 11:53, fred wrote:
On Wednesday, October 21, 2020 at 6:55:58 PM UTC+1, soup wrote:
On 21/10/2020 18:19, Andrew wrote:
On 21/10/2020 18:17, rick wrote:
I have a need to find a replacement screw
Luckily thread is nothing esotericÂ*Â* M4 x 8

If a Phillip head .... but the head is fairly wide ~10mm and pretty thin.

Anybody know if there is a name for this type of screwÂ* ...

https://flic.kr/p/2jXJRyz

I would call that a bolt of some sort, rather than a screw.
Does it taper at all at the 'sharp' end ?. Difficult to say
from the pic.

Machine screw.
But then much like the difference between a ship and a
boat, I don't think it has ever been detailed when a machine screw
becomes a bolt.

As Lord Mountbatten told his mother.'You can put a boat on a ship but not a ship on a boat"

especially if the boat is a submarine and 1000 feet underwater

On 23/10/2020 15:56:02, michael adams wrote:
"Fredxx" wrote in message ...

I don't understand why you persist.
https://www.leytonfasteners.co.uk/bo...w-information/

Common UK parlance for a bolt and a set screw is that there is thread the entire length
of the set screw, whereas a bolt is only partly threaded.


Clearly the "experts" at the University of Leytonfasteners along with Professor Turnip
have never heard of "roofing bolts" either.

https://www.google.co.uk/search?q=ro...w=1024&bih=642

Again, you're talking of another profession. I'm sure he has heard of
them in much the same way I have come across them.

As others have said screws/bolts with a different head, in this case a
dual slotted head, are sometimes referred to interchangeably.

Is it really so hard for you to accept?

In article ,
michael adams wrote:

"Fredxx" wrote in message ...

I don't understand why you persist.
https://www.leytonfasteners.co.uk/bo...w-information/

Common UK parlance for a bolt and a set screw is that there is thread the entire length
of the set screw, whereas a bolt is only partly threaded.


Clearly the "experts" at the University of Leytonfasteners along with Professor Turnip
have never heard of "roofing bolts" either.

https://www.google.co.uk/search?q=ro...w=1024&bih=642


How about the bolt on your garden gate? Not a thread or nut in sight.
And that's before we start on bolts of lightening...

--
*Never put off until tomorrow what you can avoid altogether *

Dave Plowman London SW
To e-mail, change noise into sound.

"Fredxx" wrote in message ...
On 23/10/2020 15:56:02, michael adams wrote:
"Fredxx" wrote in message ...

I don't understand why you persist.
https://www.leytonfasteners.co.uk/bo...w-information/

Common UK parlance for a bolt and a set screw is that there is thread the entire
length
of the set screw, whereas a bolt is only partly threaded.


Clearly the "experts" at the University of Leytonfasteners along with Professor Turnip
have never heard of "roofing bolts" either.

https://www.google.co.uk/search?q=ro...w=1024&bih=642

Again, you're talking of another profession. I'm sure he has heard of them in much the
same way I have come across them.

As others have said screws/bolts with a different head, in this case a dual slotted
head, are sometimes referred to interchangeably.

Is it really so hard for you to accept?

Accept what ?

Firstly there is nothing about different "professions" in any of the sources you have
quoted. This is something you have made up, all by yourself.

Now you're also claiming that a differently configured head can change what was
previously a screw (with a thread along its entire length) - into a bolt (which is
supposed to have a partially plain shaft) but clearly doesn't.

Hint: they're called roofing "bolts" and not roofing "screws" because they're first fed
through the hole, and the nut is then threaded on. Rather than being screwed into
the hole. The shape of the head is immaterial. Like all bolts they're so called
because of the way in which they're inserted and then tightened up.

Secondly your Leytonfasters source specifically relates to "set screws".
whereas the discussion up until now has been in relation to "machine"
screws. As presumably this is also the result of "centuries of tradition", a
favoured phrase of yours I believe, perhaps you can explain precisely what
the difference is ?

michael adams

....

On 23/10/2020 16:12:47, Dave Plowman (News) wrote:
In article ,
michael adams wrote:

"Fredxx" wrote in message ...

I don't understand why you persist.
https://www.leytonfasteners.co.uk/bo...w-information/

Common UK parlance for a bolt and a set screw is that there is thread the entire length
of the set screw, whereas a bolt is only partly threaded.


Clearly the "experts" at the University of Leytonfasteners along with Professor Turnip
have never heard of "roofing bolts" either.

https://www.google.co.uk/search?q=ro...w=1024&bih=642


How about the bolt on your garden gate? Not a thread or nut in sight.
And that's before we start on bolts of lightening...

I thought read that the term originated with arrows and crossbows. BICBW