Just to keep things as clear as possible, below a pair of reproduction side stands, identifiable by the open "cup" of the swivel mount at the apex of the frame. The JMI mounts were quite different type (see further below).

Reproduction - note the open "cup" of the swivel mount.

Below, simply for orientation, general views of the reproduction swivel side stands, front and back.

Reproduction side stands, front and back.

JMI, 1964 to 1967

Swivel side stands were developed initially for Line Source 40 public address speakers. In late 1963 / early 1964, JMI adapted the idea for AC30s.

"Melody Maker" magazine, 1st February, 1964. Note that the amp represented as an AC50 is actually a T60.

Various bands had stands with hand-wheels of this type: The Dave Clark Five, The Shadows, and The Beatles - Paul's AC100 trolley, and from May, John and George's AC50 trolleys.

In the JMI catalogue of early 1964 (printer's runner February '64) the swivel side stands were £10 and 10 shillings, a sizeable amount - equivalent to around £150 today.

Detail from a picture of the Barron Knights with new equiqment on the forecourt of 115 Dartford Road, late July 1964. Note the Kenrick / Shepherd castors. These were soon superceded by Flexello wheel units. Thanks to Robert.

Cabinet mount

Trolley / side-stand cabinet mount. Dimensions: diameter 3"; body 1" tall, 1 7/8" diameter; threaded centre 1 1/2" tall; thread diameter 3/8" (British Standard Whitworth).

When fitted at factory, mounts were generally attached to the sides of the cabinets with 1 1/4" 2BA machine screws (through pre-drilled holes) and secured inside the cabinet with a plain washer, grip washer, and nut.

Friction washers for the assembly were of two types: rough fibre (the most common type) or translucent nylon. These slotted over the central drum of the mount, lying flush against its outer rim. In 1967 metal washers were sometimes used instead of fibre or nylon.

Dimensions of the washer on the left: diameter 2 15/16"; width 1/2" to 9/16". The material: a species of resin backed emery cloth.

Swivel drum on the side stands

The swivel mount on the side stands was of the type pictured below (actually a stand for a Vox Conqueror), used by JMI from 1963 to 1967 on all its trolleys. The trolley mount located over the cabinet mount and was secured by the hand-wheel

Inner diameter of inner drum 2"; fibre hoop 1/16" thick.

Hand-wheels

The hand-wheel locked the drum of the side stand tight against the friction washer. The pair below came from a set of LS40 speakers.

First style of hand-wheel design.

By early August 1964, JMI had moved to a new style of hand-wheel with stamped rather than incised logo. On the left below, the new-style JMI hand-wheel; on the right, a battle-scarred example of a Thomas Organ wheel from 1966/1967. Thomas Organ incised its VOX logos.

JMI left; Thomas Organ right.

The earliest firmly dated instance of this new logo currently known on AC30 side stands is in photos taken for JMI in September:

Photos taken for JMI in September. The new logo is apparent in the original print of the left-hand picture.

Below, the reverse of the JMI and Thomas Organ hand-wheels:

JMI left; Thomas Organ right.

Castors

Through to the autumn of 1964, JMI fitted Kenrick/Shepherd ball castors on its trolleys and stands - for the most part gold-coloured, though sometimes silver, 2" in diameter.

From late 1964, JMI went over to wheel assemblies, normally black, "2 in diameter, with bearing races.

The side stand of AC30 serial number 22789. The stand (invoiced in June 1968) cost £25.00

On the left, Thomas Organ; to the right, English.

Frames

Tubing generally 7/8" diameter, chromed; internal diameter 3/4". By contrast, full length stands (with or without castors/wheels) were normally of 5/8" diameter tubing.

Thomas Organ (USA) - 1966 to 1969

A pair of Thomas Organ side stands, made for the solid state Viscount amplifier, early 1966 to around 1969, imitating JMI, but with notable differences. The legs for instance are more sharply angled and the swivel mount is open.

Thomas Organ side stands and mounting hardware for a solid-state Viscount amplifier.

The swivel hardware was different from JMI's too, the cabinet mount a simple plate (3" diameter) with welded thread, and the "VOX" logo incised rather than stamped on the hand-wheel. The plain metal disk went between the hand-wheel and the hoop at the apex of the stand (picture 3 above).

Thomas Organ side stand hardware.

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