A Photo & Discussion Forum for Wharram Design Enthusiasts
Just bought a 38" and set up the steering but am wondering about the best way, and or system to use to add an autopilot. Any suggestions are appreciated.
On my Tiki 46 i have a garmin head / control connected to a jefa sprocket drive. Jefa make many of the drives for most manufacturers who just rebrand them (ie the garmin linear drives are made by jefa!!)and when i was building my autopilot system garmin say only the garmin (jefa!) linear drive will work with their head / control units but i saw somewhere on an obscure forum that someone had used a jefa sprocket drive . I contacted Jefa and they confirmed the rotary drive is compatible. I added a sprocket to the steering wheel shaft and ran a jefa chain to the drive unit. Has worked perfectly for over 8,000 miles. The only issue i had was some slight chain stretch within the first month and i needed to add in a small chain tensioning pulley as due to the mounting location i couldnt adjust the position of the drive to remove the slack so the chain is now a slight triangle shape with the adjustable pulley taking up the slack on one side..
You'll need a rudder feedback unit (from Jefa) which i found tricky to mount right at the stern in line vertically with the rudder lashings. It wasn't cheap at around £2000 ( in 2013) for the drive , sprockets, chain feedback unit etc but its never let me down.
I have Garmin instruments, autopilot, wind, and speed depth. All nmea and smart displays. The autopilot is a dedicated display but the others can be configured to display any of the inputs.
Here is a link to what i have : https://www.jefa.com/steering/products/drives/sprocket-150nm.htm
You can also search the forum for using a small and cheap linear drive connected to a trim tab on the rudder. This apparently works well. The drive moves the small tab which then forces the rudder in the opposite direction. Also if you look at Ann and Nev Clements (Peace iv) profile i believe they used a modified windvane system that had the air blade removed and this top bit was controlled by a cheap linear drive. I'm sure i recall them doing a post about it..
Another good place to ask is the wharram catamarans page on Facebook. https://www.facebook.com/groups/1104053236329219/
Tiki 46 Spiral Tribe
I am using a Raymarine wheel pilot and a Windpilot, I would choose them again
If single handing then I recommend both a windvane and an autopilot. Dragon (T38) has these systems and they are great.
The autopilot is a Raymarine wheel system and the windvane is made to Hanneke's design.
Both reliable, accurate and cost effective.