I've wanted a couple of these imposing examples of rolling stock for a few years; more than anything else to go with the Fish Engine I built.
Idly browsing Ebay about this time last year I bought a pair of GWR Siphon H vans quite cheaply, thinking at the time that they were close enough to build easily into convincing models of the fish vans.
Errr.... nope.
They're too long, too high, the roof profile is wrong, the bogies are too big, the layout of the external strapping is wrong, the number of doors are wrong...
.... so since then they've sat on a shelf whilst I've gotten on with other things and considered how to go about a conversion.
The first step is to lose the extra length. You need to remove 20mm, and this I took out of the middle of the underframe. I should point out I removed the underframe trussing first and kept it safe, intending to re-use it when the time comes. The two halves of the underframe were then reunited with a good piece of plastic sheet over the joint to reinforce it.
Shortening the overall length brought the over-sized bogies into focus. Having removed them from the underframes, I cut either side of the mounting pins and set those bits aside. I had to lose 14mm from the bogie and by luck the bolster the mounting pins push through is 14mm in length! So that 14mm was cut away, then the bolster filed down (it wouldn't then fit between the wheelsets...) and the whole lot glued back together.
White areas are where I've reinforced what's left of the bogie.
On to the bodywork.
Having cut 20mm out the middle of the underframe, it must therefore follow that I had to cut the same out of the body. Rather the simply cut it out of the middle, and end up with a weak joint top to bottom in the middle of the van, I took stock of what I had. Not only is the body too long, it is too high and the roof is wrong. There is nothing therefore to be gained by keeping as much as possible in one piece. Therefore I separated the sides of the Siphon van from the roof and the ends, and then removed 18mm (20mm less the 1mm thickness of the moulding at both ends) from one end of the van side.
My intention at this point was 'simply' sand down the Siphon strapping, replace it with something more appropriate, and leave it there. But the more I thought about it, the more I came to the conclusion that this really wouldn't answer, and so I eventually decided that the upper halves of the sides would have to be scratchbuilt. Therefore I cut the sides down to 12mm in height, and as by this time they looked a little woebegone I mirrored them (so the right side becomes the left, and vice-versa), and scored planking on what used to be the inside face. I then glued these to the underframe to properly brace the joint.
At this point I felt that the structure was solid enough to take a craftknife to the solebars and remove the footboards under the removed doors and suchlike. This done I then fitted 3mm strips of plastic to form a new solebar face.
Casting around for a new roof, I found a Triang Mk.1 roof in my spares box. I offered this up to the drawing I'm working to (to be found in the back of Volume 3 of George Dow's Great Central) and found it to be a reasonably close match. I cut it down to 180mm in length, removing the excess out of the middle so as to retain the large mating surfaces at each end. All of the ventilators, panel seams, rainstrips etc. were then sanded off of it.
The part removed from the middle of the roof was then used as a handy template to use for plotting out the roof profile when drawing up the ends. These ends were cut from 0.5mm plastic sheet, and glued into place. The roof was then glued in.
Next stage will be to build the slatted upper sides and the external framing.
