Finger Engine Crank Ratios Dec. 17, 2014 By Kaje at https://sites.google.com/site/lagadoacademy/home

This page is based on a sketch submitted by “blogwich” at this link: http://www.homemodelenginemachinist.com/showthread.php?t=16437&highlight=treadle+engine The drawing below is for horizontal finger engines. The length of the connecting rod centers is the length of the hypotenuse C of a right triangle as shown below.

TOP CRANK THROW

B

C

AXLE CENTER BOTTOM CRANK THROW

OVERALL CRANK THROW

12 "

12 "

A

OVERALL CRANK THROW

FINGER PAD END

PIVOT POINT OVERALL CRANK THROW X 1.5

B

C

A

"finger-engine-ratios-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.

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Finger Engine Crank Ratios Dec. 17, 2014 By Kaje at https://sites.google.com/site/lagadoacademy/home

This page is based on a sketch submitted by “blogwich” at this link: http://www.homemodelenginemachinist.com/showthread.php?t=16437&highlight=treadle+engine The drawing below is for vertical finger engines. The length of the connecting rod centers is the length of the hypotenuse C of a right triangle as shown below. OVERALL CRANK THROW = 2XB

B

B

A

C

TOP CRANK THROW

A

AXLE CENTER

BOTTOM CRANK THROW

C

PIVOT POINT

PIVOT POINT

OVERALL CRANK THROW

FINGER PAD END

OVERALL CRANK THROW X 1.5

"finger-engine-ratios-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.

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