Easy-Peasy Carriage Build or ‘How to build a carriage with no drawing, no measuring, and little time’
One of the vehicles I wanted to add to my collection for use with my ‘Firefly’-class locomotive was the early type of 6-wheel ‘open’ 2nd-class carriage. There is a full-size replica at Didcot Railway Centre, as shown below:
Didcot Railway Centre – Replica ‘Fire Fly’ and train
At first glance, those panelled sides might look to be a modeller’s nightmare but 3D-printing makes it extremely simple!
There are drawings of this carriage, by Eddy Lane in the appropriate Data Sheet from the Broad Gauge Society, so my first step was simply to import a copy of his drawing, as a ‘Canvas’, into ‘Fusion 360’. The drawing shows the overall length as 27’ 2½“ (i.e. 108.8 mm in 4 mm/ft scale). Again, ‘Fusion 360’ makes it very easy to scale the ‘Canvas’ by means of a ‘Calibrate’ command, which simply requires the length of one reference line to be stated.
Now that I have learned about some of the tools that ‘Fusion 360’ has in its armoury, I have realised that there are many aids to creating arrays of similar features, such as the regular panels on this carriage. In fact, I only needed to create four types of rectangle: ( i ) the outline of the complete side, ( ii ) a ‘window’ opening with rounded corners, ( iii ) the upper side panel, and ( iv ) the lower side panel. I simply created one each of the required types, in registration with the ‘Canvas’ . After that, I could use the ‘Pattern’ tool to replicate as many identical rectangles as were needed to complete the entire carriage side! The same method can be used both for the ends and for the internal partitions.
Thus, a few simple steps were all that was necessary to turn a published drawing into a three dimensional model. The overall procedure is illustrated below:
Stages in converting a published drawing into a 3D model, using 'Fusion 360'
I now had three ‘printable’ bodies that I transferred to my ‘Cura’ software, to produce a ‘sliced’ model suitable for my printer. Since these individual components only take a few minutes each, to print, I laid out all five partitions together as a batch, for which the total print time was only 45 minutes. I also printed the sides and ends in pairs, with similarly short print times.
Set of Printed Partitions created as a single job
To assemble the parts, I fixed the ends and all the partitions to one side, using super-glue, starting from one end and adding the partitions one at a time. I then weighted the assembly until the glue had cured.
Steps in assembling the components parts of the model
After completing this side by adding the final end panel, I applied super-glue to the outer edges of all the partitions and the two ends. I then offered up the remaining side, pressing it into place until the glue ‘caught’. I laid the model on its side and weighted the upper surface until the glue had cured.
To show the end result of less than a day’s work, I added a chassis and a roof from one of the carriages I had already built:
My ‘easy-peasy’ carriage
Of course, there are lots of finishing touches to add. The purpose of this short post was to show how a seemingly complicated design can be created quickly and easily, by making use of the tools available in 3D design software.
Edited by MikeOxon