Join Date: Oct 2007
Location: Beacon Falls CT USA
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Auto-pilot installation strategies on quadrant steering
I'm stumped. My quadrant steering mechanism looks VERY different from the pictures in the Sirad manual. I will post pictures as soon as I have them, but for now, here's this issue...
For starters, the working area is tight. The entire mechanism occupies an enclosed interior crawl space, bordered on either side by a quarterberth to port and an exterior lazzarette to starboard. The aft end of the area is closed off - it's a bulkhead. Therefore, the only real access is from behind the companionway ladder, proceeding aft into the crawl space. There are small access ports from both the 1/4berth and the lazzarett, but they offer limited access.
What I found when I crawled up in there was that the quadrant afixed to the rudder post is facing aft. It has 90-degrees of travel using stops that are afixed to the interior walls of the crawl space. And it's big - the diameter of the semicircle it creates in its full range of travel is about 30 inches. Again, the whole range of travel keeps the quadrant aft of the rudder post. Given it's aft-facing orientation, I can't see the quadrant very well - let alone get create an attachment point for the actuating arm of an Autopilot.
And even if I did have access, I'd never be able to fit the AP drive unit in the crawl space - the outter edge of the quadrant just clears the interior walls of the space
Furthermore, the pully system is on plane with the quadrant, so even if I could attach the drive arm to the quadrant, and I punched a hole into the 1/4 berth to mount the drive unit, the rod of the drive unit would interfere with the mounting brackets of the cabling/pulleys that are driving the quadrant.
I did notice, I do have good access to the rudder post itself. There's about 6 inches exposed below the attachment point of the quadrant.
I need some strategies to solve these space and access constraints. Some thoughts I've had that need feedback:
1) Can I connect the AP drive arm to a bolt or similar structure attached to the quadrant, but pentrating well below it - giving me the ability to mount the drive mechanism below the plane of the pulley system?
2) Can I create a NEW point of attachment by using the exposed area of the rudder shaft, allowing me to orient the drive unit 90-degrees from the traditional orientation? I'm talking about not using the quadrant at all, but rather, creating a new structure on the rudder shaft, for the sole purpose of attaching the drive arm of the AP unit. The rudder post is 2" diameter stainless. How could I do this without comprimizing the integrity of the post and with confidence it wouldn't "slip" under load?
Last edited by Pub911; 01-22-2008 at 12:26 AM.