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Meindert Sprang
 
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Default Sizing Hydraulic Rams

"Glenn Ashmore" wrote in message
news:isYDb.5581$JD6.2101@lakeread04...
That makes sense but he wants to mount the rams parallel to the rudder
which, if the setup is roughly 200mm square will set them at about 45º
to the "virtual tiller" in the center position. That arangement will
reduce the effective ram force by about 1/3. To complicate matters, the
Vetus MTC72 is 487mm long in the center position so the ram pivot has to
be mounted 287mm forward of the pintle. The geometry becomes a trapezoid
rather than a parallelogram and puts the action out of balance. A quick
Autocad sketch indicates 99 mm out and 140 mm in. He would have to use
two rams or the rudder would turn one way faster than the other.


Indeed!

Meindert