Maryburgh Folk

Maryburgh Community Collage

The double-headed split pin



An original drawing of the idea for the powered wheelbarrow and is the only information available about it.


Frank Menzies' sketch for mobility chair.


Another sketch for mobility chair


Frank Menzies hand written notes.



Protective sleeve for Bendix gear.

Magazine cutting re Bendix gear.

Starting device for Anson bomber.


Original design diagram for the starting device.


The Anson Bomber.

Frank Menzies - more inventions

1.  The double-headed split pin

Depicted here is the double headed split pin or Scottish split pin designed by the late Frank Menzies, Maryburgh.

The idea of the double head was in the event of the outer head being damaged the pin could still be removed by using the secondary head, thus allowing the pin to be used more than once.

Just another idea from the ingenious mind of the exceptional engineer, Frank Keith Menzies.

2.  A powered wheel barrow

3.  Mobility Stool/Chair

This description was provided by the late Donald Menzies.

The wheelchair was not really what is recognised as such.   As my mother got older and very much afflicted by arthritis, my father devised a mobile stool on which she could sit at a height suitable for working at sink or worktop level, and on which she could move around the kitchen or other rooms without pain.   The stool was moved by rotating handles at hip level, which, by light chains, propelled the floor wheels; both handles were independent, so when one was turned forwards, and the other turned backwards, a complete circle was possible without forward or backward movement.   All this seems complicated but in reality was quite practical.  See some of his original sketch ideas.

Frank's handwritten notes read:

The device consists of a tubular structure having two driving wheels and three castors.  A seat, which is adjustable for height, is provided.  This enables the device to be used either as a stool or chair.  The device is propelled by a handwheel on each side which drives each driving wheel by chain.  The handwheels are quickly detachable and can be fitted in one position, where the device is used as a stool, or in the other position where it can be used as a chair.  A flat plate is provided for the feet to rest on.  A brake is provided which locks both driving wheels when mounting the device or when working at a bench or machine.

4.  Protective sleeve for the Bendix gear on car starter motors.

This is a device to ensure that the Bendix starter pinion in a starter motor does not stick in its helix, in spite of dirt and stiffness on the threads.

The magazine article reads:
MENZIES BROTHERS, CONON BRIDGE, Ross-shire, have designed a simple attachment to ensure that the Bendix starter pinion does not stick in its helix, in spite of dirt and stiffness on the threads.
Our sketch shows the simplicity of the device.   Mounted on the end plate of the motor is a flanged sleeve which is split axially, an annular contracting spring reducing its diameter.   On the pinion is an extended sleeve which is a fair fit in the fixed sleeve.
In action, assume that the pinion is in mesh with the starter ring.   When the engine fires the pinion is driven back along the helix in the ordinary way, causing the pinion sleeve to enter the fixed sleeve, where it is lightly braked and gripped.    At the next start the shaft revolves but the pinion, which tends to resist rotation due to its inertia, is further restrained by the grip of the sleeves.    It must, therefore, travel axially into engagement, entering the starter ring with practically no rotational movement.    Once the sleeves are out of engagement the pinion behaves normally.    As soon as the engine starts the pinion is thrown back again into the grip of the fixed sleeve. 

5.  Starting device for Anson Bombers

Again the description for this comes from the late Donald Menzies:

Starting the Anson Aircraft was, in the early days, carried out in a similar fashion to turning over a vintage car in the days before self-starters, i.e. by a starting handle.     As the aircraft engine was much larger and more difficult to turn over, gearing was necessary between starting handle and engine, resulting in the handle having to be turned very fast indeed in order to get the engine over t.d.o.    This caused the mechanic doing the turning to break sweat, so my father, who was a Flight Sergeant at the time, devised a starting handle with an electric motor to take the strain.    The tapered shaft as shown in the sketch below, was inserted where the manual starting handle usually went, the torque handle held firmly by one hand to resist counter rotation, and the switch button pressed.

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