< Sandboxes >
The sandboxes for the C53 loco are mounted on both sides of the boiler, cutting through the running boards. To optimize limited space, it features a complex shape with curves both vertically and horizontally, making it quite challenging to fabricate. The side view (right drawings) shows that the upper angle is for attaching the sandbox itself to the boiler, while the lower angle supports the running board.
In live steam models, a scale sandbox doesn’t function well, so I decided to repurpose it as an oil tank for natural drip lubrication of moving parts, including the central rod.
First, prepare the front, rear, and top plates from 1.2mm brass sheet. Cut them to shape using a fretsaw, then bend the front and rear plates as described below.
To achieve the specified radius, I used a jig combining angles and round bars. The material is clamped and bolted to bend it. The front plate is bent into an S-shape, and the rear plate into an L-shape, requiring two different round bars.
The angle-based jig can only bend to 90 degrees, which results in a dull angle due to springback. To address this, I used a vice and flat bar to hold the straight sections and added the final bend by hand.
Drill the necessary holes in the bent plates for assembly.
Assemble the three plates with brass angles, roughly cut the outer plate, place it on top, and trace the shape with a scriber. Cut the outer plate with a jigsaw and attach it with brass angles.
For the inner plate, bend it to match the cross-sectional shape of the front and rear plates before cutting. Use 0.5mm sheet for finer adjustments.
Attach the angles to the front and rear plates before tracing to ensure a tight fit.
Cut along the trace with a fretsaw, which is tricky due to the curves. The photo shows the process while it is underway.
Cut a round hole in the top plate with a fretsaw, and insert a ring made from brass pipe. The ring has a step for height positioning.
The photo shows sandbox brackets on the boiler cleadings. It was reported in May.
Attach the angles to the sandbox, place it on the brackets, and transfer the fixing holes. Simultaneously, position the running boards and the support angles.
Disassemble and drill holes for fixing the lower angles.
Seal all joints with high-temperature soft solder for using the sandboxes as oil tanks, except for the top plate, which remains removable. After sealing, fill it with water to check for leaks.
Finally, drill screw holes at the front lower part of the sandbox for the sand traps. Each box has three traps, each secured with four screws, and the central hole is for oil flow.
At this stage, it was discovered that these are C53 late-model sandboxes. The early-model sandboxes, intended as a prototype, feature lower rear ends that are cut at an angle rather than being rounded. As remaking it is a hard task, I will attempt modifications, but I will stop here for now..