One further part was made for the bending tool that we have constructed over the past couple of issues - an 'anvil' to enable sharp bends to be made precisely. This is an example of a 'custom-designed' part for a specific application (achieving very tight radius bends), although many other possibilities exist for other 'custom' parts, to fit into the same place (U-channel base section) in the bender. This part was fabricated from a piece of 30mm x 16mm x 750mm mild steel bar. Fortunately, such bar is readily available, with the correct width and thickness dimensions, so the only fabrication required was to cut the bar to length and then to mill the V-groove along its length. This is not straightforward to do, particularly on a mill with an X-travel of less than the required 750mm and it required careful setup. The end-elevation drawing of the anvil is shown in Figure 7. Essentially the whole part is a 750mm extrusion of this end-face. The basic setup used is shown in Photo 36. Two V-clamps were used, the smaller of which was held in a machine vice (to the right in the photo) and the larger of which was supported on a collection of 123-blocks. Parallels were used to provide some positional adjustment - one was used on each V-block, although only the left-hand one is visible in the photo. The workpiece needs to be precisely level and precisely parallel to the mill-table. The latter is relatively easy to achieve, with a little patience and an edge-finder. In the former case, we used two methods: the first was to deploy a digital inclinometer, with a magnetic base.
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