Author Topic: Raymarine auto pilot linear drive  (Read 1209 times)

stbtack1

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Re: Raymarine auto pilot linear drive
« Reply #15 on: April 17, 2019, 04:05:06 PM »
Just curious, how has reducing the stop angle affected boat handling in tight spaces? I am thinking of going 8" on the tiller arm as a compromise. I figure loaded my boat would be about 20,000 lbs. 
Billy Ellis
Salty Dog 1981  P365 Hull 364

Nereid

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Re: Raymarine auto pilot linear drive
« Reply #16 on: April 18, 2019, 02:47:06 PM »
Hey just took her out the other day for the first time since the addition.
In truth I hardly notice the difference.. If anything just a bit higher rpm to walk the transom but not much else.
In comparison to the wheel pilot, this one has been really great. it drew 1-3 amps under a moderate 5ft chop and went to 6 momentarily when we got broadsided by a rouge biggie, it did not show any issue of struggle or issue maintaining course.. So far/overall we are very happy with it. We are set to start our crossing next month and cruise the rest of the year, so i'll be sure to give a tried and trued testimony.
Run the quick 'recommended' displacement calcs for torque to boat displacement to see if 8" works, I seem to recall it is close to 20k lb.
S/V Nereid, Hull #193
www.instagram.com/afloataboard/

stbtack1

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Re: Raymarine auto pilot linear drive
« Reply #17 on: April 18, 2019, 05:46:15 PM »
I think the displacement is 17,700. Fully tanked up it jump to 19,250. Add gear and I would guess 21,000 but that would be loaded to the max at the start of a long cruise. The vast majority of time I would be less than 20,000 lbs.
Can you still turn her within her length?
« Last Edit: April 18, 2019, 05:49:08 PM by stbtack1 »
Billy Ellis
Salty Dog 1981  P365 Hull 364

Nereid

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Re: Raymarine auto pilot linear drive
« Reply #18 on: April 19, 2019, 09:54:09 AM »
So based off of what Raymarine lists for their drives' vs boat displacement, there are two options: a linear fit, or some exponential/polynomial variation. With linear, a 8" arm will equate for a 19.2klb boat where as a polynomial fit would equate to a 21.3klb boat.
So with a 8" you would be close to or at the limit to what Raymarine would consider the Max displacement of their Type 1. Where if you went with a 11" say for example would equate to 26.5klb linear and 25.4klb poly, which at the worst would be rated 4k or 2 tons higher, which would equate to less power required in heavy seas.
Not sure how you mean to turn in her length, but we get in and out of our slip no problem with a 5' davit and ~60' of horizontal clearance to enter the slip (so she still turns about the same).
I only had to move the stops out 1" to meet (just before the ends of the autopilot). Before the install I could turn the wheel helm about 3 times over in a direction and after the install it goes 2.75 times over so not a huge difference.
Hope that helps? ???
S/V Nereid, Hull #193
www.instagram.com/afloataboard/

stbtack1

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Re: Raymarine auto pilot linear drive
« Reply #19 on: April 19, 2019, 08:02:59 PM »
Absolutely. We ended up installing it at 8.25 but the bronze tiller arm I bought is capable of going all the way to thirteen. Not that would want to but I can always move the system out if necessary. We actually mounted to the cockpit floor so it goes fore and aft.  You have provided some excellent information. Thank you.
Billy Ellis
Salty Dog 1981  P365 Hull 364