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  • Originally posted by Bloozberry View Post
    Lookin' good there Joel. That transaxle is going to be one-of-a-kind... I can't wait to see more of it as it gets further down the development pipeline.

    As for the headlights, if I could offer one piece of advice it would be this: make sure there is zero play in whatever linkage/gear combination you end up using to raise the pods, and if you can, try to design the linkage so it has an over-center locking feature. Both will help minimize the pods from jiggling from road vibrations in the "up" position. I've found this the most frustratingly difficult problem to solve on my 308 replica, and there's nothing worse than having an on-coming car with headlights that vibrate or jiggle.

    Keep posting your progress!
    Bloozberry: thanks for advice on the headlights. I'll have to factor it into the design.
    Joel Heinke
    Be original; don't be afraid of being bold!

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    • Firstly, I’ve got to say that designing and fabricating these headlight mounts/mechanisms has turned into a very time consuming endeavor. Maybe it’s that I’m trying to locate something with an oval face that sits at a slightly upward sloping angle, needs to be positioned with symmetric accuracy so both sides will look the same, and requires a rigid mounting such that the headlight beams won’t bounce around on roads with a rough surface. In other words, I’m trying to position something that has no flat surfaces, no corners, and no part of it resides in true horizontal or vertical planes. This translates into taking many measurements and many re-measurements using a ruler and small level to verify the headlight bucket positioning as the fabrication goes from cardboard templates to sheet metal parts, to a welded/fastened together unitized assembly.

      Given that context, I determined the best way to mount the donor Fiat 850 headlight buckets was to wrap them in a sheet metal can that clamped down snuggly on the donor bucket. I discarded the idea of welding or screwing mounting provisions directly to the donor buckets because they are made of very thin sheet metal and I didn’t want any of the mounting bits to be visible when the headlights are viewed through the outside oval glass covers.



      Some bucket positioning adjustability is achieved on the legs that attach the mounting can to the pivot shaft by having oversized holes with fender washers to clamp the parts securely together. Shaft collars are used to attach the legs to the shaft. I added a second set screw to each collar for better gripping on the shaft along with drilling/tapping the 6-32 screw holes in the collar sides for attaching the legs. You’re probably by now starting to see why making these mounts has been so time consuming.



      The electric motor gearbox has a 5/8” round shaft with a 1/8” wide slot across it. The shaft/slot was used to hold a spiral spring as part of the window regulator mechanism. With the spring removed, this shaft/slot provides a secure, non-slip attachment point for the headlight pivot shaft. Using a lathe, I turned up a connector with ” ID on one side, 5/8” ID on the other and welded a piece of 1/8” flat stock across the larger opening for engaging the slot in the gearbox shaft. Here are all the parts assembled for first trial run at raising the headlight.



      It worked!! There are still some smaller details to work out but the basic design seems to be solid. The headlight raises and lowers smoothly and the only wiggle is some free play in the electric motor gearbox. I think this free play can be addressed/mitigated with a spring or perhaps a cam with indents for up and down positions. Now to repeat the process to build the headlight mount for passenger side, hopefully this will only take half the time of the first one.
      Joel Heinke
      Be original; don't be afraid of being bold!

      Comment

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