Autopilot installation when rudderpost is raked

[chris95040]

Hi folks,

I'm looking into adding a hydraulic-ram autopilot this winter. The difficulty is that my rudder post is not vertical, it rakes back about 25-30 degrees off of vertical.

The ram I'm looking at, the HLD-2000, claims that it needs to be mounted "upright" with no more than 5 degrees tilt in any dimension. Subsequent diagrams make me think this might not apply to axial rotations though.

To accommodate my rudder post's rake the ram would need to be mounted with an _axial_ rotation (axial meaning, rotated around the axis of the piston) equal to the rake (namely, 25-30 degrees). This is the only way the unit would remain in-plane with the tiller attachment point across the whole range of motion.



Maybe there are some fancier univeral-jointy attachment gizmos for this situation.

[UNCIVILIZED]

I wish I knew how to scan in a diagram, as I know a way how to make it work. But describing the schematic for said solution is overly complex to explain via keyboard.

That said, have you contacted the company & asked about this conundrum, & the reasons whey they specify that the AP be mounted thusly? Is it due to a sensor in the unit, for detecting rudder angle, or? And you might also inquire as to why this is important, given that it's going to be in a sailing vessel, & thus heeled over most of the time.

Also, I'm having a bit of trouble picturing things in my head at the moment, but is there a way that an arm attached to the rudder post, which is bent so that it's in the horizontal plane, work?

It'd be worth it too, to do a Google search for pictures of Auto Pilot installations, to perhaps get some ideas, & or solutions.

BTW, what's the make & model on the AP in question? It'll help us with finding you a solution. Ditto if we know the make & model of the boat, plus if you could post any pics of where (as in the space/area) you plan to install it.

[colemj]

There isn't a problem with that Ram in that configuration. As long as you can mount it normal to the rudder arm or quadrant, it is OK. That type of mount might be an engineering problem, but the operation of the Ram in that attitude will not.

The 5 degree angles requirement is only within the plane of rotation, not the rotation plane itself. In other words, it does not want to be pushing up or down on the tiller arm itself. It is very happy laying at an angle that is normal to the tiller arm.

Mark

[autumnbreeze27]

Our rudder is raked as you described. We have 2 quadrants, one for the AP and one for the helm. If posting a pic of our setup will help you let me know and I'll take some pics.

I'm guessing the 5 degree tilt requirement basically means "it needs to be lined up with whatever it's pushing and pulling"

[Paul L]

One thing to watch for if you mount the cylinder off the horizontal plane is to make sure that the bleed location is accessible and on the upper side.

[GordMay]

Originally Posted by Paul L

One thing to watch for if you mount the cylinder off the horizontal plane is to make sure that the bleed location is accessible and on the upper side.

It’s a Simrad HLD-2000

"Do never install the unit upside down! (The air valve should be facing upwards.) The HLD must be installed horizontally only. No more than ± 5 degrees tilt is allowed at any position, as illustrated on figure 1. The HLD should not act as an end stop for the rudder."

See ➥ http://www.simrad-yachting.com/Root/...50-2000_EN.pdf

[chris95040]

Thanks folks,

Uncivilized- good point on digging into why they specify this. It's a simrad HLD2000, but I'm just shopping and not really tied to anything.

They might just be talking about the angle between the yolk/tillers plane of rotation and the drive unit's plane of rotation, but they might be talking about keeping a bleeder as the highest point. But it looks like the bleeder is on the pump, and this can be separate from the cylinder assembly if a 'split' configuration is used.

Anyways, the documentation stinks.

Is there usually a bleed point on the cylinder body itself, or can this be done from the pump assembly (assuming the pump is the highest point).

[Redcoat]

Checkout Wagner n-40 or 60 mounts anyway.

[Paul L]

If you want to check with another vendor, you could call PYI (pyiinc.com) and ask about the L&S Hydraulic drives. PYI has good install support and the L&S drives are very robust, French built.

[chris95040]

Got a reply from Simrad:

From: NS Support <ns-support@navico.com>

Motor pump horizontal. Ram don't care



They aren't a talkative bunch, but it looks like the horizontal geometry requirement was for just the motor+pump. So as long as I go with a "split" unit, where the ram + pump assy aren't integrated, I should be cool.

[Boatyarddog]

Pretty sure the air valve means is the air purge point.
You'd want hat at the top because air might stay in the ram.


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