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Spitfire Mk.IIa 1:72 Scale

Spitfire Mk.IIa 1:72 Scale

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A model replica of a Spitfire Mk.IIa during the Battle of ...
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3012/10 Keel Ballast for Bellissima

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Keel Ballast for Bellissima
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2159.6 Propeller Set Prince of Wales

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Propeller Set Prince of Wales
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2013.6 Propeller Set Theodor Heuss

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Propeller Set Theodor Heuss
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2011.6 Propeller Cap San Diego

2011.6 Propeller Cap San Diego

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Propeller Cap San Diego
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Porsche 934 RSR Vaillant 1:24 Scale

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Universal Joint - Red

Universal Joint - Red

£2.54

Modular type universal joint, requires inserts to complete. Old Part No. ...
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Plain Coupling Insert 4mm

Plain Coupling Insert 4mm

£2.29

4mm Plain Insert, Includes grub screw Old Part No. C8007
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Plain Coupling Insert 3.2mm

Plain Coupling Insert 3.2mm

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3.2mm Plain Insert, Includes grub screw Old Part No. C8016
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MFA RE-540/1 3 -Pole DC Motor Inc Mount

MFA RE-540/1 3 -Pole DC Motor Inc Mount

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Plain Coupling Insert 5mm

Plain Coupling Insert 5mm

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5mm Plain Insert, Includes grub screw Old Part No. C8008
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Universal Joint - Black

Universal Joint - Black

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Modular type universal joint, requires inserts to complete.
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MFA 540/550/600 Motor Mount Bracket

MFA 540/550/600 Motor Mount Bracket

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90 deg Metal bracket for 540/550/600 complete with screws.
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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: €165.47 (Inc VAT) / US Dollars: US$153.22 (Tax Free)


Quantity:  


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

Customers who bought this item also bought:
1. Hawk BL 50A HV N6~18/Li 2~6 Brushless ESC (Ref: P-FS-HWK050)
2. Fusion 3551/05 Brushless Motor 840kv 35mm Outrunner (Ref: M-FS3551/05)
3. 2221.1 Graupner Flexible 3 Pin Coupling Single 5-7mm (Ref: G2221.1)

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: €65.17 (Inc VAT) / US Dollars: US$60.34 (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: €41.40 (Inc VAT) / US Dollars: US$38.33 (Tax Free)


Quantity:  


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

Customers who bought this item also bought:
1. Revell Aqua Color #43 Middle Grey Matt 18ml (Ref: RV36143)
2. Revell Aqua Color #5 White Matt 18ml (Ref: RV36105)
3. Plough Anchor 60mm (Ref: CMA83)

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: €170.09 (Inc VAT) / US Dollars: US$157.49 (Tax Free)


Quantity:  


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)

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)

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: €10.21 (Inc VAT) / US Dollars: US$9.45 (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. HD Coupling 5mm to 6mm (Ref: MA5756)
3. Threaded Coupling Insert M4 (Ref: MA5630)

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: €20.40 (Inc VAT) / US Dollars: US$18.89 (Tax Free)


Quantity:  

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: €17.00 (Inc VAT) / US Dollars: US$15.74 (Tax Free)


Quantity:  

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