Modification of launching trolley

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Ernst Fellner
Posts: 5
Joined: Mon 26 Mar 07, 19:49
Your Country: Germany, Bad Windsheim

Modification of launching trolley

Post by Ernst Fellner »

The axle of the rear wheels of original Quorning trolley are located quite near the centre of gravity of the boat. This yields especially when the amas are folded so the centre of gravity moves even more astern. Result is that about 95% percent of the boats load are on the rear wheels. When you slip the boat on the ramp the front wheels even partially loose ground and the pressure of the rear wheels is enormous. You can’t move the trolley on soft/loose ground with the original Quorning wheels. So our trolley had from the beginning broad tires which are filled with foam (done by Harbeck, Waging a.S.; the necessary air tire Pressure would be too high. Load on one rear wheel about 1200 kp !). Therefore Harbeck made two additional wheels with a rugged bearing, see the Photos. Between the wheels is an additional adjustable support which is screwed down during road transport, see the pictures. So our trolley now has 6 wheels
Our road - trailer ( “Sattel-Auflieger”, Airbrakes, see old Forum) was made as well as the modification of the trolley by Harbeck Fahrzeugbau, Waging a.S. , Germany.
There is now no more risk of the boat tipping backward at the ramp.

Besides we slip the boat with folded amas. Jens Quorning suggests to slip not folded (because of unfavourable lever-arm at the amas - joint when the sterns of the amas come afloat first). But we experienced no problems at a 13% steep ramp. For slipping i hade made a wooden bar fixed under main fuselage and amas, preventing them to rise; but this is not necessary and we use it no longer.
Weight of boat and launching trolley is about 2400 kp. You need a really strong (electric) winch to pull the boat back to the trailer !
Please click on any of the photos to see them enlarged!

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