The majority of the work on the clutch was cleaning the different parts.
This is a diagram of an exploded clutch. This allowed us to see how we needed to assemble the clutch. We also had a nut in our clutch that was not included in the diagram that was missing from our clutch. We spent a lot of time looking for this piece as it was crucial in the function of the clutch.
The clutch did not need much repair, but the final product is much cleaner than when we started.
This is an exploded diagram of the entire engine that showed us how the clutch and transmission interact with each other. The clutch rod, number 141, which is engaged by the clutch cable, goes from the transmission into the clutch.
This shows the mainshaft and layshaft gears, both in diagram and in real life.
This shows the transmission in the case. The middle photo shows the plate and forks, which make it possible to change gears by shifting the middle gears on both the layshaft and mainsheet gear.
If you open our powerpoint, you will be able to see our transmission shifting gears in this video. It starts at 4th gear, shifts to 3rd, then 2nd, then neutral, before ending at 1st.
Our mainshaft gear was rather abused when we began work on the transmission. Some of the gears had fused to the shaft from overheating and the innermost gear had lost a tooth. We were able to find this tooth, as seen above, in the case and were able to analyze it with Professor Arnold to understand why it broke off of the gear in the first place.
We began by cutting the tooth with a diamond saw. This includes a video, which can be seen in the powerpoint.
The small piece of tooth was mounted in epoxy so that it would be easier to polish. We first started with a high grit sand paper and slowly made our way down to the finest grit sandpaper, allowing us to get the smoothest, almost mirror-like finish, on the piece of tooth.
We were able to see that the tooth was indeed case hardened by dropping it in acid and quickly transferring it to water to etch the surface as to be able to see the different makeups.
We then used a Scanning Electron Microscope to see the different elements that the tooth was composed of. We were also able to see close up pictures of the structure of the material.
The hardening test was done to different spots of the tooth to see the different hardnesses of different locations. This was important because it lined up with our theory that it was case-hardened. The tooth was clearly brittle because it broke and flew off of the machine when too much pressure was applied to a corner of the tooth. We came to the conclusion that the tooth broke off due to an inconsistency in the metal and that it was brittle and case hardened.
Thank you for a clutch semester! Have a gear-shifting summer!
