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Specification sheet for G.A. high tension waterproof magnetos, detailing features, types, and dimensions.


Identifier  ExFiles\Box 4\5\  05-page096
Date  17th November 1920 guessed
  
PAGE 1
SPECIAL FEATURES of the
G. {Mr Griffiths - Chief Accountant / Mr Gnapp} A. {Mr Adams}
High tension Waterproof Magnetos

Design.
Silent running.
Ease of maintenance.
Maximum efficiency.
Ease of dismantling & repair.
Rotation both ways.

All types of G. {Mr Griffiths - Chief Accountant / Mr Gnapp} A. {Mr Adams} Magnetos are fitted with :
(a) an indicator showing, at any moment, the next cylinder to fire.
(b) an automatic timing device.

N. B. — The attention of manufacturers is drawn to the fact that by a simple adjustment the armature of any of the G. {Mr Griffiths - Chief Accountant / Mr Gnapp} A. {Mr Adams} Magnetos may be made to revolve in either a clockwise or an anticlockwise direction.

G. {Mr Griffiths - Chief Accountant / Mr Gnapp} A. {Mr Adams} Magnetos :: Electric lighting :: JARNAC Carburetters :: Arecal :: Refrigerators :: Foot warmer :: Pumps :: Sheet-iron.

PAGE 2
TYPES of the new
G. {Mr Griffiths - Chief Accountant / Mr Gnapp} A. {Mr Adams}
High Tension 4 & 6 Cylinders Magnetos

4 cyl. Magnetos to be driven at engine speed.
6 cyl. Magnetos to be driven at speed 1 1/2 times greater than engine speed

Type G S suitable for engines up to 60 m {Mr Moon / Mr Moore} /m bore.
Type GR {George Ratcliffe} suitable for engines up to 80 m {Mr Moon / Mr Moore} /m bore.
Type HS {Lord Ernest Hives - Chair} suitable for engines up to 100 m {Mr Moon / Mr Moore} /m bore.
Type HR suitable for engines up to 120 m {Mr Moon / Mr Moore} /m bore.

The figures following the letters indicating type of Magneto show number of Cylinders.

MEASUREMENTS IN MILLIMETERS

DIMENSIONS IN MILLIMETERS
Type | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R
GS4 | 142 | 127 | 15 | 35,5 | 42 | 6,5 | 23,5 | 12 | 176 | 62 | 43,5 | 91 | 75 | 77 | 61 | 58 | 10 | pas 1,5
GR {George Ratcliffe} 4 | 143 | 136 | 17 | 33,5 | 43 | 7,75 | 24 | 12 | 188,5 | 55 | 43,5 | 91 | 75 | 77 | 61 | 58 | 10 | pas 1,5
HS {Lord Ernest Hives - Chair} 4 | 155,5 | 146,5 | 15 | 35,5 | 35,5 | 11,85 | 33 | 13,5 | 202 | 50 | 64 | 98 | 50 | 80 | 82 | 61 | 45 | 10 | pas 1,5
HR4 | 171 | 168 | 15 | 35,5 | 35,5 | 11,85 | 33 | 16,5 | 202 | 50 | 64 | 110 | 50 | 80 | 84 | 61 | 45 | 10 | pas 1,5
HS {Lord Ernest Hives - Chair} 6 | 171 | 168 | 17 | 35,5 | 35,5 | 11,85 | 33 | 16,5 | 205 | 50 | 67 | 110 | 50 | 80 | 82 | 61 | 45 | 10 | pas 1,5
HR6 | 171 | 168 | 17 | 35,5 | 35,5 | 11,85 | 33 | 16,5 | 205 | 50 | 67 | 110 | 50 | 80 | 84 | 61 | 45 | 10 | pas 1,5
  
  
From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).


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