Giant Walking Dragline...continued
The model is fairly accurate to the prototype of the Rapier W1400 dragline. The best article that I have found on the subject is on page 31 of the March 1990 Constructor Quarterly. This gives good clear photographs, unlike the grainy ones in the April 1952 and October 1957 Meccano Magazine articles. There is a very nice model built by Nick Rudoe that is closer to the prototype. Articles on the Giant Walking Dragline are not as common as articles on the Giant Blocksetter Cranes. This may change with time now that the modelplans for the original have been released.
It was a very pleasing model to build, being well balanced. The walking mechanism was very well designed, unlike the 1962 Meccano Magazine model. To digress slightly that model had the boom mounted too far forward of the base. This resulted in the need to balance it with lead in the rear of the motor housing. All this unnecessarily increased the weight of the model and stressed the walking mechanism.
I used the instructions for the revised winding mechanism that Ian Stoney provided. My one suggestion is that the winding mechanism should have the worm gears placed after the gear engagement mechanism. This way the worms could act as automatic brakes. You could be more radical and put in a completely new motor system. The model follows traditional Meccano designs in having one large electric motor driving all mechanisms. Individual electric motors for each system with electrical rather than mechanical control would make the model easier to operate.
I also had to modify the walking shoes by placing spikes in them to provide grip. If you dont do this they slip on most surfaces. Three short pivots, Elektrikit part 550, on each foot worked well.
Having built two versions of the model I had the same dissatisfied feeling while operating them. You have to spend quite a bit of time familiarising yourself with the controls before you can operate the model smoothly. A fraction of a seconds inattention and one of the winding drums will spin away on you and you have lost control of the boom or the bucket. As a consequence of this Im currently working on (among other things) a miniature version of the same model. Im still collecting and painting parts for it but should have it finished within a year. Im using Märklin 95mm diameter wheels (part 10 395) for the base and narrow angle girders (Exacto parts 275) for the boom.
|The next two pages describe the Meccano Magazine Giant Walking Dragline that was published in the 1952 & 1962 magazines.|