View Full Version : Rudder post connection

02-23-2009, 11:15 PM
I am working on Bolger's single-handed schooner and specifically working on the rudder assembly. The rudder assembly fits into a rudder box similar to the daggerboard box. The top part of the assembly is thick top and bottom connected by 4 posts at the corner. So, most of the top part is open. The rudder post is 1" stainless steel rod passing through the rudder assembly down to the rudder blade.

Now the top of the post just has a hole through it with a pin through it that sits on a washer on the top of the rudder assembly:

It seems like there ought to be a better way then just have a pin spinning on a washer to hold the rudder post in the assembly and to provide the rotation for steering.


Any better ways to get the rudder post into the rudder assembly ?

02-24-2009, 08:55 AM
First consideration,how old is the boat and has this arrangement worked well for how many years? If it has, simple is good,if there is any wear on the pin and washer replace them.
If the shaft is sloppy going through the rudder box, you could line the box with bronze or composite bushings. Check out last months WoodenBoat issue on glass meets wood.You could also modify the top bearing if that is the problem. any pics of the problem area?

Todd D
02-24-2009, 10:19 AM
If I was doing it I would make a couple of changes. First I would put in a stainless steel tube through the rudder box. The tube would have a 3" diameter x 3/16" stainless bearing plate welded to the top for the rudder head fitting to bear on. I would make the rudder head fitting by turning down a piece of 3" diameter stainless round bar to make a flange with a hole for a 1/4" through bolt for attaching it to the rudder post. I would use a derlin washer between the rudder post flange and the rudder post flange.

I might also box the stainless rudder tube with close fitting wood and reinforce the wood box with some knees.


Jim Ledger
02-24-2009, 10:24 AM
Engineer, right?:D

Brian Palmer
02-24-2009, 10:37 AM
This has worked on other boats built to the same design, so it should be fine. Remember also that a rudder shaft is not spinning through 360 degrees, like a wheel on a vehicle. It just goes back and forth. The pin only has to keep the shaft from sliding down farther into the box, so there is not that much strain on it. You could probably sail this boat several thousand miles before the pin or washer wore out.:D


02-24-2009, 12:31 PM
Engineer, right?:D

I'd guess he'e an engineer who works for DOD.

Todd D
02-24-2009, 05:19 PM
Hey guys, watch the insults. I am not an engineer although I used to have engineering students in some of my classes. Retired scientist, now very small boat builder.

Jim Ledger
02-24-2009, 05:27 PM
No insult intended at all. A little ribbing, maybe, but definitely no insult.:D

02-24-2009, 08:28 PM
When I get to designing such jewelry, it usually takes me a few tries to get down close to the budget.

No insult intended.

03-05-2009, 07:39 AM
It's unclear if you are building or just repairing the boat.Bolger is a good designer.However,if you feel that something needs a little extra bracing or support,do it.Make the modification now while you're there at the area in question.It will give you piece of mind,and there will be no thoughts of, should I have redone that.Think things through,so the modification will be safe for yourself and passengers.