Chassis, steps and diaphragm’s.

So sit back in your comfy (?) 1st class seat and have a read about my chassis design. I am having to rewrite this due to a computer crash as I was editing it and I lost 2 paragraphs of text, now I have to remember what I had written. The seat image above is a sample of the 1st class seating, this is not the specific one for this carriage and isn’t sitting very well but it gives an idea of what the interior will look like.

Now on to the chassis, my chassis is made from ply and a resin impregnated board, that I can get in various thin but strong sheets. This has allowed me to create a accurate looking C channel rails and appropriate cross strapping. It has also allowed me to create the body hangers that stick out from the rails that add so much to the look of these carriages. I am using Kadee #821 couplers except on the outside end of the HR carriages which use a Kadee #820. This also allows a larger mounting area on the ends for people to use other styles of couplers to suit their Loco’s.

The bogie’s are assembled from plywood and assemble into 2 sides that are bolted together. This allows them to be painted up before fitting of bearings and wheel-set’s, the wheels in the samples are plastic LGB wheels but all carriages will come with Kadee #950s which I feel are the best looking and true running Australian cast style wheel commercially available. Finally a 3d printed side frame detail piece is glued on to complete the look of the bogie. The completed bogie is then bolted to captive nuts assembled within the chassis, allowing for adjustment of tension .

Next thing to show are the truss rods and steps, they are made from brass rod and plywood for the treads. The truss rods are just bent to shape and soldered together. I will be supplying a 3mm MDF jig to make this easy and confirm correct shape after soldering so they fit into the chassis sides without putting incorrect tension on them. The thickness of these were one of the compromises I had to make as they are a little heavier than prototypically correct, but with a coat of black paint you can’t tell and it does make them stronger. The steps are also made from bent brass rod and fitted through the treads of ply and side rails and glued in place. Doing it this way makes them reasonably strong and not likely to get damaged when handling or running.

The above image also shows the new 3 layer doors which gives a more correct period looking door. All the glazing glues into the inside layer of the sides for easy assembly after paint and interior stain are applied.

Finally today an image of a diaphragm with top spring and buffer plates. I am still playing with the diaphragm and deciding whether to cast it hard or soft and flexible. If I do it hard it will leave a gap between carriages but a small block of foam fitted inside will make it look good at 1 metre, if I go flexible it does mean that the buffers will rub and this could add issues on some layouts. Decisions, decisions, decisions. Until next time, enjoys your trains and your railway.

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