[SEL] National Gas Engine

[Listerdiesel]

On 1/13/06, Vivas1993 at aol.com <Vivas1993 at aol.com> wrote:
> Hi folks,
>  I've bought a 9 1/2hp National Gas engine made in the UK, the engine  dates
> around 1905-06. I'm guessing that the nuts & bolts on this engine are  the
> Whitworth type threads.
> Is there a source for new studs, nuts & bolts, because several of the
> original ones are in bad shape.  A reprint of a manual for this engine  would also
> be very much appreciated.
>  Thanks,
>  Dwight Vivas
>  Petersburg, VA.
>

Original Whitworth sized nuts and bolts are no longer made
commercially, but there are specialist suppliers in the UK that make
them.

Later "British Standard Whitworth" or BSW nuts and bolts are
available, as are BSF or "British Standard Fine" in some sizes.

The difference between early Whitworth and later BSW is the size of
the hexagon. The earlier sizes were appreciably larger, but were
reduced during WWII and rationalised along with BSF threads so that
there was a common range of spanner sizes (not size for size) and the
reduced hexagon meant that less metal was used to make the fasteners.

We were able to buy mild steel hex bar in Whitworth sizes up until a
few years ago, and have a small stock of bar in the workshop.

Peter



--
Peter A Forbes
Email: listerdiesel at gmail.com
Web: www.oldengine.org/members/diesel