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SZ1013.8 Shackle M2.5 15x11mm (Pack of 4)

SZ1013.8 Shackle M2.5 15x11mm (Pack of 4)

14.56

Shackle M2.5 15x11mm Pack of 4
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Elbjorn Icebreaker

Elbjorn Icebreaker

179.99

Billing Boats Elbjorn A typical trawler from the North Sea, built ...
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SZ1013.7 Shackle M2 12.2x7.6mm (Pack of 4)

SZ1013.7 Shackle M2 12.2x7.6mm (Pack of 4)

12.73

Shackle M2 12.2x7.6mm Pack of 4
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SZ1013.1 Shackle M1 7x4mm (Pack of 4)

SZ1013.1 Shackle M1 7x4mm (Pack of 4)

9.30

Shackle M1 7x4mm Pack of 4
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92301.5 Rudder Soil

92301.5 Rudder Soil

2.71

Rudder for Soil Mini Yacht
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92301.1 Sail Set Soil

92301.1 Sail Set Soil

8.21

Sails Set for Soil Mini Yacht
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Graupner Outboard Motor with Electric Motor

Graupner Outboard Motor with Electric Motor

64.58

Graupner replacement Electric outboard motor assembly for the Silver Spirit
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Graupner Mini Jet Drives (Pack of 2)

Graupner Mini Jet Drives (Pack of 2)

36.50

Graupner Mini Jet Drives Pack includes 2 jet drive units and ...
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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 - Red

Universal Joint - Red

2.26

Modular type universal joint, requires inserts to complete. Old Part No. ...
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Brass Rod 1.0mm 1 mtr

Brass Rod 1.0mm 1 mtr

0.72

Brass Rod 1.0mm Diameter x 1000mm
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Plain Coupling Insert 2mm

Plain Coupling Insert 2mm

2.08

2mm Plain Insert, Includes grub screw Old Part No. C8004
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1022 White Wood Filler

1022 White Wood Filler

4.90

White wood filler, very light, quick drying and sands easily, specially ...
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Planking Techniques for Model Ship Builders

Planking Techniques for Model Ship Builders

10.99

Planking is one of the most important and least often addressed ...
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AP9105W Dull Black 18ml

AP9105W Dull Black 18ml

2.18

Sold in 18ml bottles, Admiralty Paints Dull Black is a scale ...
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HM Yacht Chatham 1741 1:64

HM Yacht Chatham 1741 1:64

87.00

Caldercraft HM Yacht Chatham H.M. Chatham Yacht was launched in Chatham ...
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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: 170.73 (Inc VAT) / US Dollars: US$155.65 (Tax Free)


Quantity:  


Customers who bought this item also bought:
1. Robbe Heavy Duty Coupling 5-5mm (Ref: R1436)
2. Raboesch Bow Thruster 25/28mm x154mm (Ref: RAB108-05)
3. CEM 750S Motor (Ref: CEM750S)

Related products:
1. 49mm Impeller for CEM Jet Drive & Graupner Jet Drive (Ref: CEM2001)
Graupner Mini Jet Complete with Motor

Graupner Mini Jet Complete with Motor

Graupner Mini Jet
Includes Motor and Jet Drive

Length approx. 110mm.Width approx. 58mm,
Height approx. 50mm
Part No: G2349

Price: 57.47 (Including VAT at 20%)
Euros: 67.24 (Inc VAT) / US Dollars: US$61.30 (Tax Free)


Quantity:  


Customers who bought this item also bought:
1. Fusion 3551/05 Brushless Motor 840kv 35mm Outrunner (Ref: M-FS3551/05)
Graupner Mini Jet Drives (Pack of 2)

Graupner Mini Jet Drives (Pack of 2)

Graupner Mini Jet Drives
Pack includes 2 jet drive units and couplings
Motors not included

Length approx. 110mm.Width approx. 58mm,
Height approx. 50mm
Part No: G2349.1

Price: 36.50 (Including VAT at 20%)
Euros: 42.71 (Inc VAT) / US Dollars: US$38.94 (Tax Free)


Quantity:  


Related products:
1. JP Power 400 Motor (Ref: P5510370)
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: 175.49 (Inc VAT) / US Dollars: US$159.99 (Tax Free)


Quantity:  


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

Customers who bought this item also bought:
1. UHU Plus Acrylit 2 30g (Ref: UHU48315)
2. Fusion 3551/05 Brushless Motor 840kv 35mm Outrunner (Ref: M-FS3551/05)
3. Graupner Motor Mount for JET Propulsion Unit 6 Booster (2395.1) (Ref: G2395.1)

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: 3.50 (Inc VAT) / US Dollars: US$3.19 (Tax Free)


Quantity:  


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

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 & Graupner Jet Drive

49mm Impeller for CEM Jet Drive & Graupner Jet Drive

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

Price: 9.00 (Including VAT at 20%)
Euros: 10.53 (Inc VAT) / US Dollars: US$9.60 (Tax Free)


Quantity:  


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

Customers who bought this item also bought:
1. 4mm Super Styrene Triangle 90 Degree 1000mm Length (Ref: RAB405-54-METRE)
2. Robbe Heavy Duty Coupling 5-5mm (Ref: R1436)
3. HD Coupling 5mm to 6mm (Ref: MA5756)

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: 21.05 (Inc VAT) / US Dollars: US$19.19 (Tax Free)


Quantity:  


Customers who bought this item also bought:
1. 2347.7 Nozzle Guide Vane for Jet Unit 5 (Ref: G2347.7)
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: 17.54 (Inc VAT) / US Dollars: US$15.99 (Tax Free)


Quantity:  


Customers who bought this item also bought:
1. 2347.5 Sealing Ring for Jet Unit 5 (Ref: G2347.5)

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