There are also "carriage" bolts with conical heads specifically for flat car decks, and I have seen such on an EJ&E 70-ton flat. These allowed for a fully flush surface.

David Soderblom
Baltimore MD

On 2005 Apr 22, , at 04:14, STMFC@... wrote:

Message: 5
Date: Thu, 21 Apr 2005 23:53:50 -0500
From: "Tom Jones III" <tomtherailnut@...>
Subject: Re: DRGW 6500 series flat

"Carriage bolts" is the correct term for bolts that have a rounded head with
a small square boss below the head at the top of the bolt shaft/threads. The
top of the bolt indeed looks like a rivet driven through the wood. Carriage
bolts are very commonly used to bolt down wood to metal structures, much
more so than standard hex head or square head bolts. This is because the
bolts do not prove to be a snag to loads, and because only one person is
needed to install them, as the square boss below the bolt head catches in
the wood and keeps the bolt from spinning while tightening. Rivets would
almost never be used to hold wood to a structure, as wood simply cannot
stand the riveting process without splitting, and once driven, a rivet is
not replaceable, but wood does wear out rapidly.

Carriage bolts were originally used for bolting together the frames and
structures on carriages, hence their name. They are very nice looking when
installed on an exposed surface, such as one might find on a wagon, etc.
They would be only slightly exposed on a flat car deck, and because loads
would tend to wear them on the tops, rust and other weathering would be
common after only a few uses of the car.

Tom Jones III

David Soderblom
Operations and Data Management Division
Space Telescope Science Institute

The flat head style carriage bolts are generally known as elevator
bolts. Some of these have the square shank like a carriage bolt but
other have an all round shank with a slot in the top to hold it with
a screwdriver as it is tightened. Northern Pacific war emergency
boxcar NP 28129 has these slotted style to hold down the running
boards. I know as I'm currently removing nearly 100 of them so the
wood running boards can be replaced.

Richard

--- In STMFC@..., David Soderblom <drs@s...> wrote:

There are also "carriage" bolts with conical heads specifically for
flat car decks, and I have seen such on an EJ&E 70-ton flat. These
allowed for a fully flush surface.

David Soderblom
Baltimore MD

On 2005 Apr 22, , at 04:14, STMFC@... wrote:

Message: 5
Date: Thu, 21 Apr 2005 23:53:50 -0500
From: "Tom Jones III" <tomtherailnut@c...>
Subject: Re: DRGW 6500 series flat

"Carriage bolts" is the correct term for bolts that have a

rounded

head with
a small square boss below the head at the top of the bolt
shaft/threads. The
top of the bolt indeed looks like a rivet driven through the

wood.

Carriage
bolts are very commonly used to bolt down wood to metal

structures,

much
more so than standard hex head or square head bolts. This is

because

the
bolts do not prove to be a snag to loads, and because only one

person

is
needed to install them, as the square boss below the bolt head

catches

in
the wood and keeps the bolt from spinning while tightening.

Rivets

would
almost never be used to hold wood to a structure, as wood simply

cannot

stand the riveting process without splitting, and once driven, a

rivet

is
not replaceable, but wood does wear out rapidly.

Carriage bolts were originally used for bolting together the

frames and

structures on carriages, hence their name. They are very nice

looking

when
installed on an exposed surface, such as one might find on a

wagon,

etc.
They would be only slightly exposed on a flat car deck, and

because

loads
would tend to wear them on the tops, rust and other weathering

would be

common after only a few uses of the car.

Tom Jones III

David Soderblom
Operations and Data Management Division
Space Telescope Science Institute

I think what your referring to is a "plow bolt" Todd Horton