I finished the idler arms, with the bolt-on inner arm which will be used to adjust the tension:
Here it is, with idler wheels set on there, just for planning purposes at this point. Spacing etc will be determined later to line up with front drive wheels, and the bogey road wheels.:
Added square tubing to the front of the frame. Notice the 3″ wide gap on each side. This is where the pulleys and belts will run, so leaving it open give me a nice range of angles the belts can be at… which leaves me options for motor placement etc later on:
Added the tube in the front of the frame, which the fixed axles (5/8″ bolts) fit into. Still need to add more supports for it, and cut the center out, where nuts will go on the end of the axle bolts:
Drive wheel installed. This is very helpful for determining other measurements with the bogies, rear idler wheel spacing, etc.