My Wooden Airplane
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Cleaned New Crankshaft

Well, I got the new crankshaft from Nitron. I had a little scare when I tried fitting the Safety Shaft into the nose. It wouldn't fit! Yikes, now what? The whole (okay, the main) reason why I went with the exchange crankshaft was because I had problems with the threads on the previous one. Now these threads were bad, too? I sent an email to Pramod Kotwal, proprietor of Nitron, and asked him if he had any suggestions. He responded almost immediately. He was very concerned, and suggested that I try running a tap through the threads again, in an attempt to clean them up. Well, I'm happy to report that that did the trick!

By the way, I'm sure the crankshaft bearing surfaces were just as shiny as the 5th Bearing hub after they had been ground and polished, but the nitriding process makes the crankshaft look like it survived re-entry from outer space! Some people polish the bearing surfaces again, but Mr. Kotwal has specifically said NOT to do that, so I won't. I did, however, clean the soot off with soap and water, and blew it dry with compressed air.

Then, just to be sure that everything fit properly, I temporarily assembled the crankshaft. On the far right is the Shortened Gold Prop Hub from William Wynne. To the left of that (the shiny part) is the hub of Dan Weseman's 5th Bearing. They are held together (for the moment) by the Safety Shaft. As you can see, everything fits together nicely. I think you can also see why (in my opinion, anyway) the 5th Bearing is what "officially" transforms the Corvair from an automobile engine into an aircraft engine. Just look at the size of it, compared to the other bearings! Without it, the prop would still be just as far away from bearing #4 (the one just behind the gear that drives the camshaft), but without the extra support. This would allow the bending moments from the propeller to occasionally cause the crankshaft to break. As you can see, this new bearing adds a significant amount of support for the crankshaft and propeller.

Total Time: 1.5 hrs.