Chuck and all — the steering configuration belowdecks on the Landfall 38s cannot support a tiller arm. The quadrant is directly below the cockpit sole, and directly above the fuel tank. There simply is no room for anything on the rudder post. Wal Bryant got a good photo of this area when he redid his steering system; I’ve taken the liberty (thanks, Wal!) of reposting one of his photos on my web server at www.postaudio.net/webserver/LF38steering.jpg. Looking past the smiley face that Wal spray-painted on his new fuel tank, you can see just how tight everything is back there.
In virtually all of the autopilot installations I’ve seen where the drive is attached directly to the quadrant, the attachment has been strengthened with metal plates on one or both sides of the quadrant wheel; this includes Bob Boyer’s setup, which he emailed me photos of. Bob, I hope it’s okay for me to take the liberty again of posting one of these photos at http://www.postaudio.net/webserver/LF38steering2.jpg. And Chuck, yes I have been involved in using Octopus hydraulic linear drives in autopilot installations; I like their tough dependability and strength, and the fact that they only have a few moving parts. One of their downsides in limited spaces, though, is the fact that the actuator rod sticks out the back of the drive a fair amount when the drive is at the short limit of travel; this can cause issues with structure nearby, limiting where and how you can mount the drive. In any case, there simply isn’t a good spot (really, ANY spot) to mount a tiller arm on the LF38. — Fred Fred Street -- Minneapolis S/V Oceanis (1979 C&C Landfall 38) -- Bayfield, WI > On May 31, 2016, at 9:50 AM, Chuck Gilchrest via CnC-List > <cnc-list@cnc-list.com> wrote: > > David, > You are spot on with that assessment. Aluminum Radial drive wheels in > particular are cast so that the steering loads are carried tangentially along > the outer edge of the wheel (in the groove). Drilling a hole in the casting > 90 degrees from the designed load plane and through bolting an attachment > point for a linear drive wheel will likely result in the cast wheel > fracturing under serious loads. If the radial was to break, you would lose > both your autopilot AND the cable steering. > I have seen several autopilot installations (not on LF 38 mind you) in > confined spaces using an Octopus drive and 8" tiller arms. Perhaps that > could be an option. Maybe Fred may have experience with those regarding > compatibility with different control heads... > Chuck Gilchrest > S/V Half Magic > 1983 LF 35 > Padanaram MA > > Sent from my iPhone > > On May 31, 2016, at 9:59 AM, David via CnC-List <cnc-list@cnc-list.com > <mailto:cnc-list@cnc-list.com>> wrote: > >> It is my understanding that attaching a ram directly to a quadrant is not >> recommended by Edson etc. Quadrants are not engineered for those point >> loads. >> >> Chuck? >> >> David F. Risch >> 1981 40-2 >> (401) 419-4650 (cell)
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