Individual Blog Week 1 (5/30 - 6/2)

During this week, I was given the opportunity to learn about the half-scale bogie and take one of the two bogies apart. The steering shaft on one of the bogies was twisted and buckled due to fatigue failure. I plan to machine a new steering shaft from a 0.50" diameter 4130 cold-rolled steel rod. Another fix that we wanted to implement was to change the amount of slop that the bevel gears experience when in motion. To do so, we plan to place a spacer or bearing between the bevel gear and the surface of the shaft, so the bevel gear does not move around when in contact with the other bevel gear. The team believes that sprocket and chain will prove to be a better and more reliable option as opposed to timing chain and pulley. However, I think that this will not be utilized within the half-scale bogie, as the tolerances are already very tight, and the bogie is not designed for a sprocket and chain drive train. The information that I have learned from disassembling one o the half-scale bogies will be used to design and manufacture the Futran bogie.

Next week, Claude will be here to present the specifications that we must follow for designing the Futran bogie. I hope that during this summer, the team will be able to get all of the fixes done and have the Futran bogie.



IMG_20170530_135945657.jpg

Figure 1
Bent steering shaft


IMG_20170530_135817213.jpg 

Figure 2
Showing the bevel gears, and the space between it and the shaft. 


Table 1
Timing belt versus chain



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