This batch of three open wagons have been sitting around as more or less complete rolling chassis for several years while I made up my mind what they were going to look like. The original plan was that they would be wooden bogie wagons with drop doors, basically a bogie version of the four wheel opens completed some time ago.
Somewhere along the path, the design changed to a riveted steel design based on the VR narrow gauge open wagons. The VR design was based on a broad gauge ballast wagon, but with more features than a swiss army knife. The first batch were built for construction work on the first ng line and had folding ends, removable corner posts, removable doors, removable side stanchions and trapdoors in the floor. The TVT version is much simpler, with fixed ends and side stanchions, similar to the later condition of some of the VR wagons after major overhaul.
The chassis and bogies are the same as the other previously built bogie wagons, jig built from wood, with modified LGB bar frame bogies, so I won't repost those photos. Refer to the old posts if interested in the details.
http://gardenrails.myfreeforum.org/about8882.html
http://gardenrails.myfreeforum.org/about9793.html
I briefly flirted with the idea of building the bodywork in metal, but eventually decided on polystyrene sheet, with punched rivets. I was still concerned how strong a polystyrene sheet open body would be in this scale, so I built a couple of ends and fitted them to one underframe as a test. The photo shows the first underframe fitted with a polystyrene floor, with the ends fixed in place.
The end is glued to the wooden under frame with contact cement and solvent was used to glue it to the floor as well. This was rigid enough to encourage me to start on a set of sides. The result after a couple of weeks punching rivets into polystyrene sheet and assembling all the bits resulted in the basic body shown in the next photo.
To simulate a wagon built from sheet metal, the sides and ends are made from 40 thous (1mm) sheet, which is well over scale, but looks reasonable. It is still fairly flexible in the flat, but as with the full size wagons, the addition of various bits of angle and the side stanchions stiffens things up enough to work in large scale. It isn't advisable to pick them up by the sides though.
In hindsight it would have made for stronger construction if the sheets used for the sides had extended down over the under frame, as the joint between the bottom of the doors and the floor is a weak spot.
The truss rod is made from 1/16" brass rod and installed in a way that they are strong enough to perform the correct function. The wooden underframes had hogged slightly while sitting on the workshop bench and the curve was straightened out when the truss rods were fitted.
This pic shows the first wagon after all the detailing was added, effectively complete except for painting. The other two models were then completed up to the same point.
This photo shows the model with a four wheel wagon for comparison. The VR ng original would sit much lower than this, as the bogies were recessed into the under frame, with the flanges just below the floor.
The next photo shows one of the models after leaving the paint shop. The TVT grey is the usual industrial rapid enamel applied by airbrush, with my own waterslide decals. Aust. open wagons weren't painted on the inside, so the interior was dry brushed with various shades of rust to resemble the usual condition of a VR ng wagon.
The rivets were pressed into the polystyrene sheet with my old, much modified NSWL riveter. These are designed for HO work and something in large scale really pushes the envelope. This time around the NWSL press had to be modified to rivet the sides, as shown in the photo.
For a rivet run along the length of a door, the tool is set up as shown on the left, although the adjustable stop should be along the table. The reach of the press isn't enough to run a vertical row of rivets on a long piece in that arrangement, so the table has to be remounted sideways, as on the right.
For anyone wondering how to press rivets into a long narrow strip for making angle irons for instance, you don't. It is easier to run a row of rivets along the edge of a sheet, then cut the strip off to the desired width, complete with rivets.
My photo track/plank isn't long enough for 3 bogie vehicles, but here is 2/3 of the batch sitting in the late afternoon sun.
Regards,
Graeme
