The crankpins leverage M0.6 bolts, with nuts buried in housings inside the back of the wheel. Those nuts are really tiny – 1 mm across the flats, and so, I had always thought I would glue them into the back of the crankpins, rather than risk having them work loose and disappear amongst the ballast. The only question was how? This weekend was the pitched … Continue reading Crankpin nuts: a war of attrition
All I wanted was two holes. Two holes for crankpins 1mm in diameter and the right distance from the centre holes in the quartering jig. It seemed simple enough when I conceived of them. But then, how to get the holes the right distance from the centre? So I made a tiny bushing to fit into the hole in the crankpin jig. Okay, that was … Continue reading Just two holes!
I couldn’t think of any reason to keep the frame pan underneath the frame now that the bearing guides are in place. So, I took the jewellers saw and hacked it away. Now the frame begins to look like a locomotive frame. Inspired, I ferreted out the 3D printed ash pan and tested it for fit. Despite having accidentally sawn off most of the nubs … Continue reading Ash pan test fit
Over a year ago, when I was working on the patterns for 622, I found that drawings imported from OnShape into InkScape consisted of many individual line segments. There had to be a better way, and Craig Townsend has found it. Here for future reference, is a YouTube video that makes it dead easy. Thanks Craig! Continue reading Stroke to Path could save me hours!
Between the extra-long jig axles and some clamping tabs that I etched into the frame pan, installation of the bearing guides was a walk in the park. I had been a little concerned that the jig axles would be a loose fit on the bearings. As it turned out they were a little snug, and I even had to sand one down a hair to … Continue reading Bearing guides installed
In 2016, I suggested that it’s time to stop running our trains as if they were a slot cars. Real locomotives have throttles and brakes, not huge speed knobs. As if in answer, Iowa Scaled Engineering developed the Protothrottle for diesels, and a thread over on Model Railroad Hobbyist suggests that we may see something similar for steam before long. That thread at MRH starts … Continue reading AR will kill the knob
At least I think they should be called jig axles. These pieces of Aluminum rod are used with the coupling rods to ensure the bearings are exactly the right distance apart. Essentially, I will pass these rods through the bearings, fix the coupling rods to the outsides, and then solder the bearing guides to the frame. This allows for a frame that isn’t 100% square … Continue reading Extra-long jig axles