How did they design this excentric shaker , I would like to make one of these.

[lake side bob]

Looking through You Tube I came across this show.
Title of it is [Wilhelm Soil Screener] the brackets around the title I added,
there is a part one and a part two.
On part 2 Wilhelm shows how the screen shakes, it uses an excentric shaft.
I would like to build a similar shaker screen but have not figured out how Wilhelm designed the excentric.
Do any of you have an idea how he did it????
More detail the better, ever a drawing or two three would be help full.
The excentric shaft is at the bottom of the screen deck, I would put it at the top of the screen deck and shake the top of the screen deck and the gravel as it slides down the screen slope, which would be 35 to 40 degrees.
At the bottom I would weld a pin on each side of the screen deck frame and place the pin into pillow block bearings mounted on the the frame of the screen box bottom where the screened soil is accumilates.
The top of screen deck would shake and the bottom would move in the pillow block bearings.
Any suggestions on how he designed the excentric shaft???

[lake side bob]

Well last evening I though it through and have my answers.
Built a cardboard model to confirm my thoughts.
No need for any one to reply to questions, as of now, a lot of readers but no replies.

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