Creating a Pantechnicon
Even after a long career in research, I am still frequently surprised by the new information that emerges from small beginnings!
After completing my Britzka model, I placed it on my BG carriage truck model for some photos. The Britzka was rather a tight fit between the truck rails, so I went back to Eddy’s Data Sheets from the Broad Gauge Society (BGS) to check the dimensions. It turned out that it is my carriage at fault and I shall revise my model to make it a little narrower (easy to do with a 3D printed design!). As I was looking at the BGS data sheets, however, I noticed that there was a very similar truck described as a 'Road Van Truck' (Data Sheet 105B). I started to investigate further and so started a new line of research ...
From the BGS data sheet, the ‘Road Van Truck’ looks similar to the carriage truck I have already modelled, except for a longer body and slightly increased wheelbase: body length increased from 15’ 4” to 18’ 6” and wheelbase from 8’ 6” to 9’ 0”. It was a straightforward task to increase these dimensions in my 3D model of the carriage truck, without having to re-design any of the components:
3D-model of Road Van Truck – revised from Carriage Truck
In describing this truck, Data Sheet 105B includes the information that “… of general interest are the notes in BGS Journal [Broadsheet] No.26, p10, which refer to the first recorded use of a Furniture Van Truck with Pantechnicon, 1847, transported by rail.” Fortunately I have the complete set of digitised ‘Broadsheet’ issues, which are available from the Broad Gauge Society, so I could look up the article entitled 'Knee Brothers of Bristol'
Knee Brothers, Bristol
‘Broadsheet’ No.26 contains an article about the firm of Knee Brothers, a removals firm in Bristol founded in 1839. According to this article “In 1844 William Knee had a special mammoth heavy version of a horse drawn spring furniture van built to his own specifications at a wheelwrights in the St. Pauls district of Bristol. The felloes of its wheels were recorded as being 9" wide. This was the first pantechnicon to travel by rail.” The first record of such rail transport was in 1847, when the furniture of a contractor for the construction of the Bristol and Exeter Railway was conveyed on the B&ER, using GWR rolling stock. There is an early advertisement by Knee brothers, which shows the Pantechnicon mounted on a GWR Road Van Truck, as shown below:
Contemporary Illustration from Knee Brothers Advertisement
According to the ‘Broadsheet’ article: “The Knee Brothers 'pantechnicon' had wagon sides and strouters (wooden supports to strengthen wagon sides) of blue-grey, similar to warship grey, with brown (possibly varnished wood(?) shafts and axles. Springs were black whilst the wheels were red (similar to wheels of later G.W.R. horse drawn road vehicles). Its tarpaulin(?) covering was dark charcoal grey with side and front owner signs of cream background with black sign writing. An italic "No. 1" was inscribed on the wagon side just inside the front strouter. Strouters on this vehicle sides, from just behind the region over the front wheels (i.e. about two-thirds along the wagon side from its rear), were slightly tilted from the true vertical towards the vehicle front for remaining length of the wagon side, whereas the other strouters appeared to be truly vertical. This practice seemed to have been commonplace with techniques of road wagon construction in the nineteenth century.”
It is also states that “The Great Western Railway broad gauge van truck on which the 'pantechnicon' was pictured was in all chocolate brown livery except for its wheels and springs which were black. Lettering "G.W.R. No. 66" was also in black” This description does not conform with other GWR livery references, which state that all parts of goods vehicles were brown, including wheels and undergear. The lettering was probably incised into the solebars, as described in Great Western Way (1st.ed). Whether it was coloured black seems questionable
Creating a Model
Apart from there being no dimensions, this description and illustration above seemed adequate for me to attempt making a model. The length of the Road Van Truck has been given as 18’ 6” and, in the above illustration, the ends of the pantechnicon are around one foot from the ends of the truck, so I have guesstimated the length of the pantechnicon as 16’ 6”. I used the perspective tools in Photoshop to ‘square up’ the side of the body to estimate other dimensions on this basis. I have described this method in more detail in an earlier post.
Estimating dimensions after perspective adjustment in Photoshop
I also had to estimate the width of the body and decided, somewhat arbitrarily, to make the width across the panelled sides 4’9”, widening to 6’ 0” above the large rear wheels. This allowed sufficient clearance for wheels with 9” felloes (i.e. rim width) to fit within the side-rails of the Road Van Truck.
Using ‘Fusion 360’ modelling software, I extruded the van body from a rectangle measuring 66 mm x 19 mm to a height of 14 mm. I then extruded the upper part of the sides to an overall width of 24 mm. I used the ‘Shell’ tool to hollow out the interior of the vehicle to leave an outer wall width of 1 mm.
For the side panelling, I drew a pair of rectangles of appropriate size, one above the other near the rear end of the side. I then used the ‘Pattern’ tool to create an array of two rows of 19 panels along the length of each side. I see this ability to create repetitive features like these panels as a great advantage of 3D modelling over other construction methods. In accordance with the description given above, I modified the front six panels so that the uprights between the panels were inclined at 5 degrees from vertical. At this point, the 3D extruded body appeared as shown below:
My first-stage extrusion of Pantechnicon body
My next step was to add the front board above the body and a series of hoops to the same profile along the length, to the tail-board. Then I designed the curved strouters, which help to support the overhanging part of the upper sides. I also created wheels of 9” width and placed them in appropriate positions, so that I could check the clearances within my Road Van Truck. The hoops were created as individual bodies, so that they can be printed separately, lying flat on the printer bed. The ‘test assembly’ of these various parts within ‘Fusion 360’ is shown below:
Test fit of my pantechnicon body on road van truck
Designing the Chassis
It’s not possible to glean much about the chassis from the available illustration but there appear to be separate under-frames for the front and rear axles, providing mounts for semi-elliptic springs above the axles.
The front underframe is fitted to a swivel mount below the floor of the vehicle body and also carries attachments for two pairs of shafts, to attach the horses. In the illustration, these shafts are shown swung upwards against the front board of the vehicle. There is no indication of a drivers seat, although this would have been placed near the top of the front board. By drawing on my experience from designing the Britzka carriage, I sketched out an underframe comprising a rectangular frame to carry the springs for the rear axle. From this, two longerons reach forward to carry the fixed ‘fifth wheel ‘, which provides a bearing for the pivoting fore-carriage. The fore-carriage is a separate component carrying the frame for the springs over the front pivoting axle, plus mountings for the shafts, for two horses.
My design for the pantechnicon chassis
For the shafts, I turned to Janet Russell’s book: “GWR Horse Power”, which contains dimensioned drawings of various types. I used one of her drawings as a ‘canvas’ in ‘Fusion 360’, from which I extruded two sets of shafts to attach to the front of my chassis.. I arranged these shafts to fit onto a cross-shaft, so that they could be raised against the front panel of the body, as shown in the illustration above, or lowered for attachment to a pair of horses. Once I had brought all the parts together in ‘Fusion 360’, the 3D design looked as below:
My 3D design of the complete Pantechnicon undergear
I could now place the body over the chassis in ‘Fusion 360’, to assess the overall assembly before printing the various components.
Printing
As usual, after all the design effort, the printing came as something of an anti-climax. Once again, I was pleasantly surprised by how cleanly my printer produced even the smallest and most delicate parts. I laid them all out for a photo, just as I took them from the printer bed (although one hoop somehow disappeared to the carpet monster and I had to reprint a second set)
For the record, the print times (estimated by the Cura software) were:
- body 67 min
- wheels (set of four) 20 min
- underframe 10 min
- fore carriage 7 min
- front board 7 min
- axles (pair) 5 min
- hoops (set of four) 4 min
- shafts 3 min
The assembly was very straightforward. Only the front board, hoops, and axles needed to be fixed into place I fixed a ‘perch pin’ into the centre of the ‘fifth wheel’ underneath the body and the fore-carriage was then slid onto this pin. Similarly, the wheels and shafts were slid onto lengths of 0,7 mm wire, which provided the pivot points.
I painted the body light grey, as described in the ‘Broadsheet’ article, while the axles and shafts are brown, and the wheel faces red.
I produced the lettering using ‘Cooper Std’ and ‘Garamond’ fonts, which are reasonably good matches to the prototype illustration, shown below.
My layout of the front panel text
After laying out the text and the Bristol coat of arms in Photoshop, I printed the front and side panels on ink-jet printable self-adhesive vinyl, which I stuck onto the 3D-printed model. The end result, without a tilt cover, is shown below:
My model pantechnicon (less tilt cover)
Rear View, showing Tailgate
Canvas Tilt Cover
For the cover, I first wrapped the body of the van in cling film, stretched over the hoops and shaped by hand. I then wrapped a length of wet plaster bandage over the cling film and smoothed it down into place. Once I was content with the general appearance, I placed the model over a radiator to dry.
My model wrapped in cling film and plaster bandage
Once the plaster had dried, I applied a rather thick layer of black acrylic paint over the bandage, working it into the texture of the surface to make as opaque a coating as possible. Once this had dried, I trimmed off the excess plaster, below the top of the body and took the portrait below:
My model with Tilt Cover added.
As I indicated at the outset, the thought of building a pantechnicon was not in my mind until I followed the train of thought that started from the BGS Data Sheets! It has proved to be an interesting model to create and I think the use of 3D printing provided a simpler course than ‘traditional’ modelling methods. All the parts were extruded from 2D drawings so, if you can create a drawing for a ‘Silhouette’ cutter, it can be turned into a 3D model! In fact, some of my first 3D-printed models were created in this way from drawings that I had previously used for Silhouette-cut carriage sides.
I notice that there is an earlier thread on this site about modelling a 4 mm scale pantechnicon from a kit. I suspect that it was the ‘Gem’ kit, which is no longer available.
Mike
Edited by MikeOxon
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