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Turn Fin Mono Mini

Turn Fin Mono Mini

£9.98

Turn Fin Mono Mini
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MZ0008 Oil Drum Red Height 95mm Diameter 60mm

MZ0008 Oil Drum Red Height 95mm Diameter 60mm

£13.99

Oil Drum Height 95mm Diameter 60mm 1:10 Scale
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1761.1 Conversion Kit to Pulley Schottel Drive I

1761.1 Conversion Kit to Pulley Schottel Drive I

£44.99

Conversion Kit to Pulley Schottel I
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2335.6 Conversion Kit to Pulley Schottel II

2335.6 Conversion Kit to Pulley Schottel II

£39.95

Conversion Kit to Pulley Schottel II
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2335.11 Servo Disc for Schottel Drive II

£5.50

ReplacementServo Disc for Schottel Drive II
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Lisbon Diorama for Lisboa Tram

Lisbon Diorama for Lisboa Tram

£49.94

To introduce this line of dioramas, we the first scene is ...
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N S Mercedes Spanish Frigate 1:85

N S Mercedes Spanish Frigate 1:85

£198.95

Occre Mercedes The frigate "Nuestra Seρora de las Mercedes" was built ...
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Joysway Waterproof Bellows (Pk2) 93 Series

Joysway Waterproof Bellows (Pk2) 93 Series

£3.50

For Joysway '93' series brushless boats. Fits over Rudder Connecting Rod ...
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Universal Joint - Red

Universal Joint - Red

£2.26

Modular type universal joint, requires inserts to complete. Old Part No. ...
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Threaded Coupling Insert M4

Threaded Coupling Insert M4

£2.08

M4 Threaded Insert Old Part No. C8011
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1022 White Wood Filler

1022 White Wood Filler

£4.70

White wood filler, very light, quick drying and sands easily, specially ...
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Admiralty Glues Thick Superglue 20g Standard

Admiralty Glues Thick Superglue 20g Standard

£2.50

Caldercraft Admiralty Glues Standard Cyanoacrylate (superglue) is a high quality modelling ...
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Plain Coupling Insert 2.3mm

Plain Coupling Insert 2.3mm

£2.08

2.3mm Plain Insert, Includes grub screw Old Part No. C8005
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Plain Coupling Insert 4mm

Plain Coupling Insert 4mm

£2.08

4mm Plain Insert, Includes grub screw Old Part No. C8007
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Universal Joint - Black

Universal Joint - Black

£2.40

Modular type universal joint, requires inserts to complete.
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Graupner Brushless Control Navy BVR 40

Graupner Brushless Control Navy BVR 40

£35.99

Controller suitable for ship models. Simple synchronisation of transmission paths. Extremely ...
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Jet Drives

Cornwall Model Boats | Hardware & Accessories | Drive Units & Outboards |  Jet Drives

Water Jet Drives

The Jet propulsion unit, also known as a water-jet unit, is primarily fitted to exclusive high-speed motor yachts, ferries, racing boots and similar full-size vessels. In principle this power system consists of a pump which sucks in water though an opening in the bottom of the hull, accelerates it by means of an impeller, then forces it out again through an opening in the stern. Newton’s law of motion now applies: the jet of water expelled at the rear generates an equal and opposite reaction in the boat’s hull.

Boats with Jet propulsion units can operate in very shallow waters, as all the parts usually mounted below the hull, such as propeller, shaft, shaft bracket and rudder, are eliminated. Initial acceleration with a jet unit is very high, and this can be a distinct advantage in certain types of boat such as dragsters. The heeling moment produced by conventional boat propellers is completely absent. Since the water in a Jet propulsion system has to cover long distances in narrow ducts, there are inevitable friction losses which require rather more energy than for an orthodox power system.

CEM Jet Propulsion Unit 78

CEM Jet Propulsion Unit 78

The new CEM JET propulsion unit is ideal for internal combustion engines and powerful brushless motors, as thrust reversal is obtained by operating the reversing flap rather than by reversing the direction of rotation of the engine. The steering nozzle incorporates an integral cooling water nipple. Suitable power plants are internal combustion engines of 15 to 30 cc capacity, and electric motors rated at a minimum of 700 Watts output power.

The Jet drive is usually epoxied into the hull, with a rectangular hole cut 65mm wide by 155mm long right up to the transom bulkhead, a circular hole approx. 55m diameter is cut into the bulkhead, and the nozzle from the back of the drive goes through that. The main control, exit nozzle is then mounted over that and screws through the bulkhead to attach to the main jet unit.

Length approx. 285mm.Width approx. 78mm,
Height approx. 85mm, Impeller 49mm
Part No: CEM2000

Price: £145.92 (Including VAT at 20%)
Euros: €175.10 (Inc VAT) / US Dollars: US$160.51 (Tax Free)


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Customers who bought this item also bought:
1. 49mm Impeller for CEM Jet Drive (Ref: CEM2001)
2. Robbe Heavy Duty Coupling 5-5mm (Ref: R1436)

Related products:
1. 49mm Impeller for CEM Jet Drive (Ref: CEM2001)
Graupner Jet Propulsion Unit 5 (2347)

Graupner Jet Propulsion Unit 5 (2347)

The new JET propulsion unit is ideal for internal combustion engines, as thrust reversal is obtained by operating the reversing flap rather than by reversing the direction of rotation of the engine. The steering nozzle incorporates an integral cooling water nipple. Suitable power plants are internal combustion engines of 15 to 30 cc capacity, and electric motors rated at a minimum of 700 Watts output power.

The Jet drive is usually epoxied into the hull, with a rectangular hole cut 65mm wide by 155mm long right up to the transom bulkhead, a circular hole approx. 55m diameter is cut into the bulkhead, and the nozzle from the back of the drive goes through that. The main control, exit nozzle is then mounted over that and screws through the bulkhead to attach to the main jet unit.

Length approx. 285mm.Width approx. 78mm,
Height approx. 85mm, Impeller 49mm
Part No: G2347
More Information...

Price: £149.99 (Including VAT at 20%)
Euros: €179.99 (Inc VAT) / US Dollars: US$164.99 (Tax Free)


Quantity:  


This item is temporarily unavailable. Please Click here for an expected delivery date.

Customers who bought this item also bought:
1. Water Outlet (Ref: MA3059)
2. Water Scoop (Ref: MA3058)
3. Silicone Tubing 4mm ID 1 Metre (Ref: P5508515)

Related products:
1. 2221 Graupner Flexible 3 Pin Coupling Double M6-7mm (Ref: G2221)
2. 2221.1 Graupner Flexible 3 Pin Coupling Single 5-7mm (Ref: G2221.1)
Graupner Motor Mount for JET Propulsion Unit 6 Booster (2395.1)

Graupner Motor Mount for JET Propulsion Unit 6 Booster (2395.1)

Special motor mount for JET Propulsion Unit 6 Booster with connecting hole for Speed 700 series and Ultra 1300-9M motors.
Part No: G2395.1
More Information…

Price: £2.99 (Including VAT at 20%)
Euros: €3.59 (Inc VAT) / US Dollars: US$3.29 (Tax Free)


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Graupner Steering Nozzle With Reversing Bucket (2346.1)

Graupner Steering Nozzle With Reversing Bucket (2346.1)

The kit contains: steering nozzle, reversing flap and frame, mount, lugs and other parts (all parts injection-moulded plastic).
Part No: G2346.1
More Information...

Price: £27.54 (Including VAT at 20%)
Euros: €33.05 (Inc VAT) / US Dollars: US$30.29 (Tax Free)


Quantity:  


Customers who bought this item also bought:
1. Graupner Jet Propulsion Unit 5 (2347) (Ref: G2347)

Replacement Impellers

Replacement impellers for the Graupner Jet Drive Units

49mm Impeller for CEM Jet Drive

49mm Impeller for CEM Jet Drive

49mm Impeller for the following Jet drive unit: CEM Unit 78
Part No: CEM2001

Price: £9.00 (Including VAT at 20%)
Euros: €10.80 (Inc VAT) / US Dollars: US$9.90 (Tax Free)


Quantity:  


Customers who bought this item also bought:
1. CEM Jet Propulsion Unit 78 (Ref: CEM2000)
2. Robbe Heavy Duty Coupling 5-5mm (Ref: R1436)
49mm Impeller for Graupner Jet Drive

49mm Impeller for Graupner Jet Drive

49mm Impeller for the following Jet drive unit: 2347 & 2348
Part No: G2347.1

Price: £9.98 (Including VAT at 20%)
Euros: €11.98 (Inc VAT) / US Dollars: US$10.98 (Tax Free)


Quantity:  


This item is temporarily unavailable. Please Click here for an expected delivery date.

Customers who bought this item also bought:
1. 2347.7 Nozzle Guide Vane for Jet Unit 5 (Ref: G2347.7)
2. 2347.5 Sealing Ring for Jet Unit 5 (Ref: G2347.5)

Replacement Parts for Graupner Jet Drives

Replacement parts for the Graupner Jet Drive Units

2347.5 Sealing Ring for Jet Unit 5

2347.5 Sealing Ring for Jet Unit 5

Rubber shaft sealing ring for Jet Propulsion unit 5 (2347)
Part No: G2347.5

Price: £17.99 (Including VAT at 20%)
Euros: €21.59 (Inc VAT) / US Dollars: US$19.79 (Tax Free)


Quantity:  


Customers who bought this item also bought:
1. 49mm Impeller for Graupner Jet Drive (Ref: G2347.1)
2347.7 Nozzle Guide Vane for Jet Unit 5

2347.7 Nozzle Guide Vane for Jet Unit 5

Nozzle guide vane for Jet Propulsion unit 5 (2347)
Part No: G2347.7

Price: £14.99 (Including VAT at 20%)
Euros: €17.99 (Inc VAT) / US Dollars: US$16.49 (Tax Free)


Quantity:  


This item is temporarily unavailable. Please Click here for an expected delivery date.

Customers who bought this item also bought:
1. 49mm Impeller for Graupner Jet Drive (Ref: G2347.1)

Cornwall Model Boats | Hardware & Accessories | Drive Units & Outboards |  Jet Drives