38-200 Below Deck Linear Drive Installation Pics and Information (Autopilot)

[Ryan L]

Finished this project today. Thought I'd share this because I'm stoked and so other people may have better luck than i had when trying to find information before starting. Happy to answer any questions and to hear if anyone sees something that may cause problems down the line...

Linear drive is an Octopus LAM7 that was modified to have a remotely mounted pump/solenoid (like their LAR models).

Autopilot is Simrad AC12 paired with AP24 control. Networked via Simnet (and 0183 for the Garmin GPS/Sounder).

Bracket is custom 2 parts- 1/2 inch G10 right-angle (two pieces of 1/2" G10 I glassed/tabbed) all epoxied in place as the "base" with the linear drive mounted to another piece of 1/2 G10 bolted to the base (so as to be easily removable for service.)

Rudder stops are epoxy coated red oak epoxied and screwed to the bulkhead with replaceable G10 "faces" fastened in place.

Rudder position sensor is mounted to a piece of HDPE (starboard) that's clamped to the drive cylinder.

Haven't had any time on the water with it yet but will post if I learn anything that may be useful.

 

[Guy Stevens]

Not bad

Question, it is hard to tell from your photos, but is the arc for the rudder sensor going to work well even if the rudder sensor is moving with the fore aft vector of the arc of the hydraulic cylinder?

Two, flip the pump around so that it is under the overhang... I know that it seems like you are going to need to add fluid to this thing, but once you get rid of the leaks and bleed it the first time, unless you take it apart you are never going to need to add fliud. Having it out of the way for getting whatever in and out of the locker will keep it from being damaged when people do get things in and out of the locker. Fill it when you must with a ketchup squeeze bottle with fluid in it, you don't need a lot of overhead clearance.

As first I thought you were trying to secure the ram with the clamps... Then I looked closer.. That was funny....

Also your rudder sensor is maxed out on adjustment in one direction. That usually means that the arc isn't quite right. Be careful with that. I have seen a lot of people get into trouble that way.


Guy

 

[Joliba]

Excellent set up, Ryan. I see that your rudder position sensor is in a good position. It appears that you were indeed careful to set up a parallelogram with the sensor arm attached an equal distance from the center of rudder post rotation and the center of the sensor rotation.
Is that an access port in the bulkhead just forward of the rudder post? I like that.
One thing I did to increase our aft compartment access is to completely remove the propane tank locker by cutting it out at the opening level on the port side just as the existing access is on the starboard side. We have CNG instead of propane and have only used that area for storage. Some people do use it for cold drinks. I find that access aft for large items is more desirable. I also built a cover over all the mechanicals, Rudder sensor, etc. so that these will not get broken if someone throws something into the aft lazarette. I do not have a good autopilot. What you have done will give you excellent peace of mind and steering power in almost any weather. Congratulations!
Mike

 

[Ryan L]

Question, it is hard to tell from your photos, but is the arc for the rudder sensor going to work well even if the rudder sensor is moving with the fore aft vector of the arc of the hydraulic cylinder?

Good catch! This is something I considered during install and to be frank I don't know if it will be an issue or not. The ram only has about 7" of throw so there is minimal fore/aft arc, especially at the midpoint where the sensor is mounted. Also, the swing of the arc is more or less the same in both directions. But what finally sold me on trying this solution was that it is an extremely simple way to mount the sensor and that the Simrad computer "learns" to correlate the sensor position with the full swing of the rudder. While at the dock you tell it when the rudder is centered, full left, and full right. Then the computer moves the rudder through the full arc stop-to-stop and uses the information to calibrate the rudder position sensor. You probably already know this but maybe it's different for other makes? We plan to do initial sea trials this week and I'll post the results. If it's any problem it's easy enough to relocate the mount. In the meantime the display seems to indicate accurate information when I manually move the wheel.

By the way, I was shooting for 35-40 degree swing and we ended up with 40-43ish. Close enough and plenty of travel for maneuvering. It leaves a few mm buffer before max-travel on the ram on each side. Another easy thing to adjust if needed (my modifying the rudder stops).

Two, flip the pump around so that it is under the overhang... I know that it seems like you are going to need to add fluid to this thing, but once you get rid of the leaks and bleed it the first time, unless you take it apart you are never going to need to add fliud. Having it out of the way for getting whatever in and out of the locker will keep it from being damaged when people do get things in and out of the locker. Fill it when you must with a ketchup squeeze bottle with fluid in it, you don't need a lot of overhead clearance.

Your ketchup bottle idea is brilliant!!! Especially while underway when it would be more difficult to pour from a container. Thanks you!! To fill it while purging/bleeding we just stuck a funnel into a short piece of 1/2" hose. The other end had a threaded connector that screwed onto the cap of the reservoir. This allowed us to tilt the entire unit (pump, ram, etc) without spilling while filling to help get all the bubbles out.

As for flipping the pump around I had not considered that but it makes sense as long as it's still easy to add fluid if needed. For us it wasn't just about adding fluid but also about easily checking fluid level and inspecting for leaks. But flipping it would probably not make that prohibitively difficult. Since we don't use that space for storage and so far have had no difficulty easily getting in and out (relatively speaking) with the pump mounted where it is my first inclination is to leave it where it is but based on your feedback I'm gonna take a good look next time I'm down there. The biggest potential damage point as it stands now is the rudder position sensor. It protrudes further into the space than the pump and is much more difficult to see while lowering yourself into the space.

As first I thought you were trying to secure the ram with the clamps... Then I looked closer.. That was funny....

So you mean you're NOT supposed to clamp the ram in place??

Also your rudder sensor is maxed out on adjustment in one direction. That usually means that the arc isn't quite right. Be careful with that. I have seen a lot of people get into trouble that way.

I'm not sure what you mean by this but I'm very interested to know if I'm may be missing something here? In all the pics the rudder is centered. The sensor arm is positioned a mm or so off center. It still has play at both extremes of the swing. The sensor is rotated relative to the ram to allow for the "parallelogram" positioning relative to the center of the rudder post, ends of threaded rod, etc. The ram is positioned slightly aft of rudder post center so maybe that's why it looks like the sensor is maxed in the pic? The ram base is gimbaled and while the slightly aft position leads to slightly asymmetrical travel it does not max out in either direction. Your thoughts?

Thanks for taking the feedback Guy. I appreciate having an experienced eye looking things over!

 

[Ryan L]

Thanks for the feedback!

Excellent set up, Ryan. I see that your rudder position sensor is in a good position. It appears that you were indeed careful to set up a parallelogram with the sensor arm attached an equal distance from the center of rudder post rotation and the center of the sensor rotation.
Is that an access port in the bulkhead just forward of the rudder post? I like that.
One thing I did to increase our aft compartment access is to completely remove the propane tank locker by cutting it out at the opening level on the port side just as the existing access is on the starboard side. We have CNG instead of propane and have only used that area for storage. Some people do use it for cold drinks. I find that access aft for large items is more desirable. I also built a cover over all the mechanicals, Rudder sensor, etc. so that these will not get broken if someone throws something into the aft lazarette. I do not have a good autopilot. What you have done will give you excellent peace of mind and steering power in almost any weather. Congratulations!
Mike

Thank you. It took a while to get it right but our parallelogram would probably *almost* satisfy my grade school math teacher...

Yes, that is an access port just forward of the rudder post. It made it much easier to drill through the post and it makes it easy to tighten the bolts on the autopilot tiller. It also makes it easy to peek in from the aft cabin to inspect the space while underway.

We were not planning to use that space for storage but I'm curious how you made covers to protect the mechanicals? Any chance you have a pic or two handy that you can post? It must be like an extra stateroom back there without the propane locker!

Thanks again!

 

[Joliba]

Ryan,
I can't find any pictures of the cover and I can't get to the boat now. Today it was -15 degrees F with 30 knot winds (-50F wind chills they say.) Too cold and windy to even get a torch lit to thaw the padlock on the compound where the boat is hauled out. San Diego must be nicer this time of year. I like your access port to the rudder post area. One thing Ericson did horribly was to provide practical access to important areas. I have added access to 7 or 8 places in Joliba, usually as the need has arisen. I'll have to keep that one in mind.
The protector for our quadrant and rudder position sensor is basically a semicircular piece of 1/2 inch plywood screwed down to the lip of wood on which the rudder stops are mounted. Attached to that is a sheet of plexiglass which we bent into a curve with a heat gun.The plexiglass hangs down from the curved rim of the plywood, protecting the quadrant, etc. and permitting gross inspection without removal. It looks a bit like a giant welder's mask for a hippopotamus. This is important for us because we depend upon that compartment to stow sails, fenders, life vests, canvas covers, etc. It prevents us from accidentally fouling a fender line in the steering mechanism.
With all the upgrades you have been making it seems that you must have big cruising plans. A circumnavigation maybe?? Your boat will be the envy of sailors at every anchorage and port.
Mike

 

[Guy Stevens]

These:



While the AP control computer can map the rudder sensor, it works best if the rudder sensor physically indicates where the rudder is. The mounting screws are in center of the slots to allow you to adjust this as necessary.

Does that make sense?

Guy

 

[Ryan L]

View attachment 13375

While the AP control computer can map the rudder sensor, it works best if the rudder sensor physically indicates where the rudder is. The mounting screws are in center of the slots to allow you to adjust this as necessary.

Does that make sense?

Guy

Yes, thanks for the clarification. I drilled the holes to where I thought the correct position was going to be. The screws are over the edge now after rotating the base to get the alignment you mention. But per your suggestion, I need to drill new holes centered in the slots in case further adjustment is needed. Thankfully that's easy enough to do. I was afraid you found something that was gonna require me to spent many more hours buried in the transom... Thank you for catching that and bringing it to our attention!

 

[Ryan L]

Ryan,
I can't find any pictures of the cover and I can't get to the boat now. Today it was -15 degrees F with 30 knot winds (-50F wind chills they say.) Too cold and windy to even get a torch lit to thaw the padlock on the compound where the boat is hauled out. San Diego must be nicer this time of year. I like your access port to the rudder post area. One thing Ericson did horribly was to provide practical access to important areas. I have added access to 7 or 8 places in Joliba, usually as the need has arisen. I'll have to keep that one in mind.

Yeah it's a bit warmer here. You guys are way tougher than we are. This kinda sums it up - http://www.youtube.com/watch?v=72mvm0tx_28

As for hatches, it's a bit off-topic but since I started the thread I guess it's ok to ask where else you added them? We have one to access under the seat in the shower, the one you saw in the transom, and are planning to add one near the aft port side of the cockpit (to better access some mounting hardware). Any chance you've cut into the settee backrests?

The protector for our quadrant and rudder position sensor is basically a semicircular piece of 1/2 inch plywood screwed down to the lip of wood on which the rudder stops are mounted. Attached to that is a sheet of plexiglass which we bent into a curve with a heat gun.The plexiglass hangs down from the curved rim of the plywood, protecting the quadrant, etc. and permitting gross inspection without removal. It looks a bit like a giant welder's mask for a hippopotamus. This is important for us because we depend upon that compartment to stow sails, fenders, life vests, canvas covers, etc. It prevents us from accidentally fouling a fender line in the steering mechanism.
With all the upgrades you have been making it seems that you must have big cruising plans. A circumnavigation maybe?? Your boat will be the envy of sailors at every anchorage and port.
Mike

That sounds like a great solution! Hippo welder masks are not used often enough in sailing...

If all goes well we're heading to the S Pacific later this year (like Mark and Vicki on their 38-200 Southern Cross!) From there who knows? But current plans are to return to San Diego after exploring a bit. Thank you for the kind words but I doubt people will envy us too much as we bob around amongst all the sexy new cruising yachts. Then again, our Ericson's are definitely unique and envy-worthy boats!

 

[Joliba]

Ryan,
Wow, sounds like a great trip. I sailed to the S Pacific many years ago in a much smaller boat. You now have a good self steering system. When I did it, our mechanical self steering wind vane was our most valuable crew member... Quiet, reliable, and efficient, using no electricity. Are you planning to install one?
As an aside, does your boat have the original 5432 engine? What type of prop does she have?

 

[Ryan L]

Engine, wind vane steering,

Ryan,
Wow, sounds like a great trip. I sailed to the S Pacific many years ago in a much smaller boat. You now have a good self steering system. When I did it, our mechanical self steering wind vane was our most valuable crew member... Quiet, reliable, and efficient, using no electricity. Are you planning to install one?
As an aside, does your boat have the original 5432 engine? What type of prop does she have?

Yes, after much consideration and research we decided to order a Monitor. In fact, I was just writing them an email. We're not in love with the way it looks but it seems to have the best overall combination of the key things we're looking for (function, customer service, availability of parts, reliability, mounting strength, emergency rudder capability, and ease of repair). What did you use? Did it work well for you? For what it's worth I've been in touch with E38 and 39 owners who have cruised with hydrovane and cape horn respectively. Our decision was based in part on their feedback.

And yes to the engine question too. We have a 5432 with a fixed 2 blade prop. She has around 2k hours and so far runs well. We replaced all the hoses (except main exhaust), boiled the exchanger, flushed and replaced all fluids, etc. Why do you ask?

When did you do the jump? What boat? Solo?? Thank you for sharing this information! Stoked to find a forum member with experience about this stuff!!

 

[windjunkee]

Ryan,

I'm coming in on this thread a little late. However, I just bought the Simrad AP24 with the AC12, etc. etc. Why did you choose to go with the octopus drive unit? Out of curiosity? I've bought the AP24 package, but not the drive unit yet.
I'm installing on my E-32 and I'm going with the Simrad Drive unit - the 350 MkII - which has the 7" throw also. Everything I read seems to indicate this is the proper one for my boat. I like your install photos. How long did it take to do the install. I'm time-crunched and thinking about just hiring someone to do the install. I have B&G H-1000 that I'm planning to network in for the wind-angle steering. What did you network with?

Jim McCone
Voice of Reason E-32 Hull #134
Redondo Beach, CA

 

[Ryan L]

Ryan,

I'm coming in on this thread a little late. However, I just bought the Simrad AP24 with the AC12, etc. etc. Why did you choose to go with the octopus drive unit? Out of curiosity? I've bought the AP24 package, but not the drive unit yet.
I'm installing on my E-32 and I'm going with the Simrad Drive unit - the 350 MkII - which has the 7" throw also. Everything I read seems to indicate this is the proper one for my boat. I like your install photos. How long did it take to do the install. I'm time-crunched and thinking about just hiring someone to do the install. I have B&G H-1000 that I'm planning to network in for the wind-angle steering. What did you network with?

Jim McCone
Voice of Reason E-32 Hull #134
Redondo Beach, CA

Hi Jim- I went with the Octopus linear drive mainly because they are extremely well built and have an established reputation for performance and reliability, they come in a variety of configurations to make installation much easier, and they have adjustable flow rates. The Octopus drives are more simple in terms of design and number of parts and I believe better suited for long distance cruising (for example they use regular automatic transmission fluid instead of specialty hydraulic oil like the Simrad unit). Octopus has exceptional customer support and answered the many questions I had while doing this install.

I used the Octopus LAR7 (R = remote mounted pump, 7" throw). http://octopusdrives.com/products/linear-drive-0

The physical process of installation took about a week but what took the most time overall was designing the mounting bracket, sourcing the various parts, etc. I created this thread hoping to save other people much of that pain. The wire runs and network components took a few days (can be done while the epoxy cures on the bracket). I put the AC12 on the forward wall of the laz and put the AP24 on the side of the cockpit adjacent to the helm (there was already a hole from the formerly installed wheel pilot). Bleeding and commissioning the Octopus only took a few hours and was actually fairly easy. Octopus provides excellent easy to follow instructions and the LAR makes it easy to angle the pump and drive arm as needed to get the final bubbles out of the system. Especially with the top mounted reservoir.

I networked the autopilot components primarily with Simnet (nema2k) but connected a Garmin GPS via NEMA 0183 using the Simrad AT10 adapter. It was all plug and play. I think the only "tricky" part was changing the settings on the Garmin to export nema (and that took all of 5 minutes). That said I had recent experience with 0183 from some other projects so it was still fresh in my mind. There are some tricks to Simnet but the instructions are fairly easy to follow. I found the diagrams of the various networking options to be the most useful. If I remember correctly the diagram was labeled "Medium" network (something like that). Pay particular attention to where the red termination plug goes.

I imagine it would be easy enough to hire someone to do the work. My guess is they will prefer to have the bracket fabricated from metal, something we considered. We ended up going with G10 and doing it ourselves because I wanted a system that I knew backwards and forwards and could modify/repair while away from fabricators etc. Plus it's that much less metal on the boat... G10 is easily modified as needed and easier to use epoxy with than metal. McMaster has a great selection and fast shipping. http://www.mcmaster.com/

Let me know if you have any other questions. The project is kind of a pain but it's worth it.

 

[Touchrain]

Monitor a good choice

We used a monitor on our 10,000 mile pacific cruise on our E38. It steered wonderfully in anything over 5 k. It probably steered 90 percent of the time. Take extra lines. Although you can swap end for end, they do wear. We had emergency rudder, never used, but make sure do a test install in calm conditions. Also, a low power tiller pilot can be attached as another backup, much less power consumption. Have a great time, I'm jealous.

 

[Ryan L]

We used a monitor on our 10,000 mile pacific cruise on our E38. It steered wonderfully in anything over 5 k. It probably steered 90 percent of the time. Take extra lines. Although you can swap end for end, they do wear. We had emergency rudder, never used, but make sure do a test install in calm conditions. Also, a low power tiller pilot can be attached as another backup, much less power consumption. Have a great time, I'm jealous.

Encouraging feedback, thank you! Very curious about your pacific cruise... You're only the second E38 I've heard of that went that route. Do you have a blog or something? We're (my wife and I) extremely interested in learning about your trip!

 

[Ryan L]

View attachment 13375

While the AP control computer can map the rudder sensor, it works best if the rudder sensor physically indicates where the rudder is. The mounting screws are in center of the slots to allow you to adjust this as necessary.

Does that make sense?

Guy

I made the change you suggested and re-calibrated with the arm centered rather than a few mm off (and with the screws now located mid arc in the slots). After letting the computer re-calibrate it now shows equal travel in both directions (35 degrees, right on our target!) vs a two degree variance. I don't know if translates to a difference in steering performance but I suspect it does. Either way it's nice to have it done "right." Thanks again for the feedback!

 

[Ryan L]

Sea Trial Results

Finally got to test test the installation in some wind and swell. We sailed about 5 hours in mostly 15-18 knots with wind chop over a 2-4+ rolling swell. We tested the system on all points of sail and with various sail combinations including unbalanced and overpowered. The autopilot drove extremely well in all situations except when running DDW with poled out genoa where it tended to oversteer a bit in response to the yawing caused by the swells/surfing. There are settings I could select to lessen that but I was having fun and didn't bother with it at the time (that might require reading more of the manual...)

One thing that surprised me was the relatively low power draw. It never really "spiked" above 2-3 amps when the autopilot was actively turning the rudder. I'm sure it would be higher in extreme conditions.

The slight movement of rudder position sensor caused by it being mounted to the linear drive did not have any discernible impact on performance. It's hard to imagine the unit working any better than it did. Other than the one situation I described above the system worked extremely well and with surprising efficiency.

One final note- I was especially surprised at how quiet it is! Almost impossible to hear from below decks (even in the aft cabin) and in the cockpit we heard only a soft sort-of rapid puttering sound when the pump engaged. It's by far the quietest pump on the boat.

 

[Joliba]

Question

Ryan,
I'm curious, when you did your sea trials with the autopilot, running downwind, were you guiding it by compass heading input or by masthead wind direction? Anyway, I'm sure it won't make any difference because, as others have remarked, your Monitor will be steering 90% of the time. (I would expect 5% hand steering and only the remaining 5% with your amazing new autopilot...with much of that while under power.)
Mike
By the way, did you get my email last week?

 

[Touchrain]

Actually, our route was Seattle-San Diego-Mexico (5 months) - Hawaii (2 months) - Alaska (2 months) - back down to Olympia. We had a blog on Tripsailor. Still can get to it, usually. Google Tripsailor Touchrain.

 

[Ryan L]

Ryan,
I'm curious, when you did your sea trials with the autopilot, running downwind, were you guiding it by compass heading input or by masthead wind direction? Anyway, I'm sure it won't make any difference because, as others have remarked, your Monitor will be steering 90% of the time. (I would expect 5% hand steering and only the remaining 5% with your amazing new autopilot...with much of that while under power.)
Mike
By the way, did you get my email last week?

Yes, got your email (thank you) but was in a mad rush to get Naoma ready for the past few days and then we were underway. I posted a few things to the forum from my phone when had service but frankly prefer sitting down rested at home to reply to emails. We got back late last night.

As for downwind- we were using compass. Our masthead stuff does not speak NEMA but we're considering the cost/benefit of upgrading that. I suspect if the computer was steering by wind it would have driven much better, and if we were steering by Monitor even better still. Nicole and I discussed exactly that while we watched the computer drive s-turns downwind. You sure you're not a mind reader?