Curious, did anyone glass in a 2x4 on the swim platform to mount their linear autopilot rather than drilling through the swim platform? I really hate to drill holes and am giving this some thought.
I had enough of the wheel pilot that came with the boat and sprung for the new Raymarine EV-1 with a type 1 below deck linear mechanical drive. The wheel pilot was pretty confused and couldn't handle any type of sea. In fact, I was better off just locking the wheel.
I read through some of the articles posted, which are very nice.
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2000 C36 MKII 1825
Jim,
I'm pretty sure that all Catalinas which use a below deck autopilot have the mount bolted thru the swim platform. I know that's the case for the 470, 400, and 380. The forces involved are much too great for lag bolts into a 2x4. Clean holes thru the fiberglass with butyl tape instead of caulking and you should be leak-free.
Tom Sokoloski
C36/375IA Past Commodore
Noank, CT
Pulled up the manual and it appears that the linear drive can produce over 600 lbs of force. Looks like I will be drilling holes.
2000 C36 MKII 1825
Jim,
I would definitely suggest you read Larry Brandt's excellent article in the Upgrades section under the Technical tab of our website. He stresses the need for "perpendicularity" of all components. I will second that requirement. The PO of my boat didn't follow that rule, and as a result, I can't turn as sharp in one direction compared to the other. You will LOVE the below-deck A/P!
Tom Sokoloski
C36/375IA Past Commodore
Noank, CT
While we are on the autopilot topic, I also have a question. We have a below deck unit and it's wonderful. However, I noticed that it instantaneously corrects the rudder and rotates the wheel back and forth rather abruptly. Is this quick motion any concern? It seems that it would fatigue or stretch the steering cable, even though the steering force is being picked up by the linear rod attachment and not the cable....still, the momentum of the wheel (weighs maybe 10-15 pounds??) spinning quickly in one direction and then the other seems like it might create wear somewhere in the cable or sheaves....or am I over thinking it?
Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B
[QUOTE=pkeyser;20444]While we are on the autopilot topic, I also have a question. We have a below deck unit and it's wonderful. However, I noticed that it instantaneously corrects the rudder and rotates the wheel back and forth rather abruptly. Is this quick motion any concern? It seems that it would fatigue or stretch the steering cable, even though the steering force is being picked up by the linear rod attachment and not the cable....still, the momentum of the wheel (weighs maybe 10-15 pounds??) spinning quickly in one direction and then the other seems like it might create wear somewhere in the cable or sheaves....or am I over thinking it?[/QUOTE]
There is some force from the mass moment of the wheel, but not much to worry about. If you're out cruising for long periods it's more of a concern in relation to the electrical current. When it steers nervous like that you're using lots more battery. Turn down the gain (might be called response) and you'll see it calm down. Essentially, you should have the gain as low as possible for the conditions. Low wind, flat seas, and few gusts allow a gain as low as 2. Downwind, gusty conditions, and large waves may require a gain of 7 or 8. If your gain is too low for the conditions it will be steering a crooked line or even broach.
Greg Jackson
SV Jacqui Marie
2004 C36, MKII
tall rig, wing keel,
Thanks. I wasn't aware of that adjustment. Do you think I can make adjustments from the autopilot gage on the pedestal? I'm slowly learning about our Raymarine instruments and figuring out how to calibrate the knot log and windex but haven't played with the autopilot yet.
Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B