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.