VERY bad idea. That drive is not going to be any where near fast enough
for an autopilot. It is a screw drive. A LOT slower than a hydraulic.

Also a hydraulic cylinder needs to be a "balanced" type with the rod
going all the way through so the displacement is the same in both
directions. Regular single ended double action cylinders have less
displacement on the rod side because of the volume of the rod. With a
constant pump speed it retracts faster than it extends and with less
force. You would never get an autopilot logic unit to control it properly.

These are more what you will need:
http://www.surpluscenter.com/sort.as...ke yword=HCP1

and the pump has to be reversable like these:
http://www.surpluscenter.com/sort.as...ke yword=HPSD

Steve wrote:
The linear drive I finally located (haven't purchased yet) is non-marine.
Rather commercial, industrial for gates, wheel chair lifts and positioning
appliactions.

I is presently available from Surplus Center
http://www.surpluscenter.com/item.as...&item= 5-1474

I'm anticipating that I will have to give some attention to marinizing the
unit, but that's what DIYs do.

Steve
s/v Good Intentions



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
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