[C320-list] Edison tiller arm extension specs for autopilot

[Tim Van de Water via C320-list]

I am in the process of installing a B&G autopilot on Coda. I need to
purchase the Edison tiller arm extension. If anyone has the specs needed
to send to Edison, I would appreciate it. I took my calipers out to the
boat to measure the OD of the rudder post and discovered that the jaws of
the caliper may not be long enough... I emailed Dale at Catalina the day
before the shutdown was announced, so no news from him.

Thanks in advance for any insights.

Regards,

*Tim Van de Water*

*SV CODA '98 #537*404.790.2208
tj.van...@gmail.com

[Allan Field via C320-list]

I did this in 2013 to my then C320. I bought the tiller arm from Edson. The
item number was 926-10-610-MKII, Tiller Arm Bore 2.85 PINNED. In 2013 I
paid $429. Hope this helps.

Allan S. Field
Sea Shadow - C387 #103 (formerly C320 #808)
Columbia, MD

[Randy B via C320-list]

Hi Tim,

I bought one 2 years ago. Contact Edson directly. This PDF form is from
the Edson web site
https://edsonmarine.com/content/EB373-2410%20Tiller%20Arm%20Worksheet.pdf
They were very helpful at Edson and I ordered it directly from them. My
specs are this:
- Tiller Arm material Bronze
- Tiller Arm Length 10 inches
- Securement method Through Bolt 3/8 inch

Mine was for a Raymarine autopilot so not sure if yours will be the same or
not. Autopilot is a game changer!

Regards, Randy

On Mon, Nov 3, 2025 at 7:00 PM Tim Van de Water via C320-list <
c320...@lists.catalina320.com> wrote:

[Richard Walker via C320-list]

We had a BNG auto pilot for more than 25 years and it did not fail us ever. I really like the idea that I could couple it to the GPS system for long transit off Southern California and not have to worry about steering the boat while I kept lookout.
Dick Walker

> On Nov 3, 2025, at 19:24, Randy B via C320-list <c320...@lists.catalina320.com> wrote:
>
> Hi Tim,

[Michael Paris via C320-list]

My rudder post OD was 2.86”. I purchased a digital caliper on Amazon for about $20 to get the measurement. The tiller arm needed to be shortened by 1 3/4”. Jeff Hare was extremely helpful with this installation.

Sincerely,
Mike
Mojo #734

[mikecolleran--- via C320-list]

Thank you, Mike.  For others who have done this, does the 10” tiller arm always need to be shortened?
Mike ColleranSea Glass#805


Sent from the all new AOL app for iOS

[wdoc1--- via C320-list]

Yes, otherwise it will hit the bulkhead forward of rudder post.Bill    DIversion #714
PS- I will forward an email chain including links to Jeff Hare's brilliant step-by-step instructions/photos.

[Tim Van de Water via C320-list]

Thanks for the great info! Any suggestions / guidance on drilling the hole
to pin/through-bolt for attachment? Is our rudder post hollow?

Thanks again!

*Tim Van de Water*
SV CODA '98 #537
404.790.2208
tj.van...@gmail.com


On Mon, Nov 3, 2025 at 9:54 PM Allan Field via C320-list <

[Mike Paris via C320-list]

I believe these notes I have below are from Jeff Hare.

Attaching to rudder post
IMPORTANT: Be sure to carefully Center the wheel and mark where the centerline of the rudder post is (aft side).
⅜” hole in tiller arm made by Epson
Drill rudder post: Use Cobalt drill bits. Start the dimple with a ⅜” bit, switch to a slightly smaller bit for the hole. Keep an eye on the angle of the drill because it’s easy to not be straight in that tight space. Use a ⅜” tap to thread the rudder post itself
Bolt: 2 ½” grade 8 stainless steel with about ½” unthreaded shoulder
Use lots of TefGel on all surfaces including threads

Cut-off measurement of arm
Measure clearance between rudder post and cabin wall (Cut-off length)
(Jeff Hare cut-off 1 ¾ ” of tiller arm)
[Hole for linear arm should be 7 ½” - 8” from center of rudder post]
Sincerely,
Mike
#734 Mojo

> On Nov 4, 2025, at 2:01 PM, Tim Van de Water via C320-list <c320...@lists.catalina320.com> wrote:
>
> Thanks for the great info! Any suggestions / guidance on drilling the hole