Penny-farthing with 1800mm wheel rim diameter, for street theatre ‘Waldwesen’.
Fork. Tubes pre-bent according to projected profile.
Fork plates, assembled in jig.
Hub for the street-theatre penny-farthing.
Design for a fork drop-out / hub bearing coupling for a penny-farthing. Sealed bearings are held with a press-fit onto the hub ends. Bearing rings are machined for a slide fit on the bearing OD and held by circlips on the hub ends. Drop-outs slide into the rings are held in place by two bolts. This design allows quick and easy separation of the fork and hub without altering the fit on the bearings. The drop-outs are lazer cut from 4mm mild steel; rings manually turned from
Head badge, CNC lazer cut from 1mm stainless steel, silver soldered to tube. The badge is a monogram of my initials, RPC.
A little hack to turn our 3-axis CNC milling machine into a simple CNC lathe for small pieces turned from soft materials with high cutting speeds. I manually turned small pins on the end of 100mm lengths of round wood stock in order to load them into a spindle collet. The lathe tool is clamped to the mill table. I used SheetCAM to generate G-code from tool paths in dxf files as for a standard 2.5D operation; a simple post-processing script then switched the X and Z axes. With the tool clamped in the machine’s Y-negative zone, the tool path must run through the Y-positive zone in the drawing. It is important to check the rapid paths generated by SheetCAM in order to avoid colliions of tool with workpiece!
More of my CNC Ruby scripts. The basic 2.5D form was first machined from the dxf. The Ruby script generated the g-code to put in the radiused sides of the triangle. The tool paths are visualised here in linuxcnc.
General purpose vertical bicycle frame jig. The adapter machined here is for locating the main tube on a penny-farthing.