I've been making bits for the shunting tractor for a while now (the one in the video in the previous post is just for testing). For the most part it will be scratchbuilt and it's a bit of a case of making up the plan as I go along... never having built a model of a wheel loader before.
The cab sides and engine cover sides have been cut out from two bits of 5 thou brass soldered together... actually they are not yet fully cut out. Somehow I hope to assemble these into a three dimensional thing resembling the real thing.
I'd assumed all along that I would do the main frames on the milling machine - the first time I've used the miller to do make a set of frames. I've had the thing drawn in CAD for a long time and decided it was time to bite the bullet and actually see if the theory would work in reality.
I didn't really know how this was going to go but I bunged in a 1mm cutter, cranked the spindle speed up to near the max and set to work on two bits of 22 thou brass soldered together. I was half expecting broken cutters but it all went very well. It took me four 'laps', each taking around an hour to get through the thickness, leaving three 'tabs' to make sure the frames stayed put while I was making the last cut.
Of course this would be an ideal job for a CNC machine but mine is of the handraulic variety. Instead I drew the cutter path in CAD , printed it out and then wrote up the coordinates of all of the places where I needed to change direction. I didn't attempt to do the diagonals - they will be finished off with a file.