Triple Eccentrics, 4th attempt success.

by John

The eccentrics are turned from 2 bits of brass, which are separated later.  It was a trial and error effort, mainly error.

I tried soldering the parts initially, but mistakenly used silver solder.  All was well until I tried to melt the solder, and so much heat was required that the thin brass parts were wrecked.

Next time I used Loctite, but during turning, the parts flew apart and were again damaged.

Finally, I Loctited the parts, then bolted them with the final bolts, then turned the disks.  This method worked, but the 6 disks required almost perfect dimensioning on the milling machine during drilling, then the lathe for turning and parting.  Altogether, very demanding.

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Attempt one, showing the brass rod blanks which I soldered then turned, then separated, then discarded.

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Final run, showing the glued and bolted brass rod, and the turned and part parted disks

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Parting the disks was nerve racking, due the fine tolerances, and the eccentrically placed crankshaft hole. But it occirred without disaster

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Final cosmetic facing in an appropriately small Unimat hobby lathe.

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The finished eccentrics, stored on a piece of 10mm silver steel. There is less then 0.5mm between the bolt head and the machined edge.     Hooray!!!!