Rudder Replacement

[Ed Valente]

After battling a wet rudder for the past couple years, I've removed it after hauling. Contacted Foss Foam who quoted $1500.00 for a rebuild using my existing stock. They gave me two options (same cost); rebuild to original specs or go with a Carl Schumacher modified design.
Does anyone have an opinion or information on either ? Also any thoughts on the quote given or reputation of Foss Foam. Boat is an Olson 911se

Thanks,

Ed

 

[Loren Beach]

Given that Carl S designed the original rudder for the 911s, I wonder what they mean when saying that they have his design for an alternate blade?
I guess that the vendor can answer that one...


Loren

 

[Grizz]

Cal 40 alternate rudder design

Perhaps this will shed some light...

The attached image shows the foil shape of the Cal 40 purchased from The Foss Company / Finco last winter. The OEM rudder was crated and shipped to CA from Chicago so that Foss could reuse the SS skeletal frame again, a benefit of living in freshwater.

The $1,500 sounds about right, although I've scrubbed that # from my memory.

The intent of the Cal 40 design (as far as I've been able to figure out) affords a deeper bite under close hauled and beam conditions, with no apparent adverse impact off wind from the slightly narrower width.

Perhaps we were hallucinating, but the helm felt as though it tracked cleaner with a bit less heel than in prior seasons with the OEM rudder.

[Note to Ed V: Shoe String is tucked away in CYW, inside/unheated, against the north wall . The rudder can be inspected whenever you wish.]

 

[Grizz]

And this as a comparison / contrast...

OK, OK, so the Olsen (sic) is misspelled, it still shows the differences between the 2 designs. This from The Foss Company, who were responsive, helpful and timely, high praise these days!

 

[Slick470]

I also found this in my various digging around the internet for Olson 911 information.

My understanding from what I remember from researching before we bought the boat was that a number of the Express 37 owners asked Carl to take another look at the rudder design. After a number of the Express 37's upgraded to the new rudder and it improved on the handling characteristics of that boat, some of the 911 owners asked for the same thing and this is the result.

Some number of the west coast 911's have the upgraded rudder and it supposedly helps in higher wind, off the wind conditions with control. We have the factory rudder, and it's been fine for where we sail, but I also haven't pushed our boat to it's limits.

 

[olsenjohn]

I think Olsen is spelled correctly.....

OK, OK, so the Olsen (sic) is misspelled, it still shows the differences between the 2 designs. This from The Foss Company, who were responsive, helpful and timely, high praise these days!

So I think you spelled Olsen correctly, at least from my POV.

 

[Loren Beach]

More about that rudder shape

Information that comes out of a thread like this getting hard to find around the 'net.
I will append (with permission) some more info I received from Timm Leslie, who races a Cal 40 and owns Danish Marine, a boat yard in Portland.

I sent this thread link along to Timm, knowing that his boat has a modified rudder, and his reply was educational (well, IMHO, at least). I learned some new trivia and hope you enjoy this as well.
_____________________________
Aloha Loren,

The Olsen is suspiciously similar to the two Carl designs that I commissioned for California Girl Cal 40 and Freewind a Cal / Ron Holland designed ½ tonner.

I also asked him to look at A Bob Smith design on Stan Honeys Cal 40, while it was on the hard at Alameda “Svendsens” – similar concept- carbon fiber post with rudder bearings...

I had Tuttle “Water Rat" make the plug, and then sent the plug to Foss to make a mold for our 24ish Cal rudders for the Yahoo Cal group. Dennis Grant of Vangmaster watched over the project, and did the float test and test fit of the rudder. The rudder had positive buoyancy, and #1 had the wrong post angle. They remade the rudder and I passed the fit test.

We had the new Cal rudder made with a next size smaller rudder post, with a greater wall thickness. This allowed us a narrower profile, and a neater NACA shape. To facilitate the rudder getting slender at the tip, the rudder post was flattened in a press from circular to nil flat at the tip.

The rakes were mechanically inserted into holes in the shaft to avoid welding issues.

Dennis Grant selected and machined Nylatron bushings for the top and bottom of the rudder tube, so the smaller diameter post, could fit in a standard rudder tube, very simply. Nylatron is a tradename for a family of nylon plastics, typically filled with molybdenum disulfide lubricant powder. It is used to cast plastic parts for machines, because of its mechanical properties and wear-resistance. We discovered that the Nylatron swelled @ 3% in water so my #1 was initially very stiff, so we added a zerk fitting to the rudder tube and put trailer grease in there, It eventually loosened, and now is very perfectly worn to fit, with no play.

A stainless split machined insert was made so the smaller post could fit into the standard tiller head.

At the end, my custom rudder one off was @$5k, making 20 plus of them at one time reduced the cost to @1.2k.

Foss kept the mold, and has been using it on their line for a number of boats.

Carl died, and so his royalty agreement disappeared (was “forgotten?”).. at one time it was $300 per rudder.

It was a great project at the time, we had a new Class rudder accepted, the boat had the benefit of greater and easier handling and restored confidence.

Numerous other fleets have the benefit of Carl’s brilliant masterpiece, and may never know it.

Thanks for stirring fun memories!

Kind regards,

*´¨)
¸.· ´¸.·*´¨) ¸.·**¨)
(¸.·´ (¸.·' ( ......….-_/)

image003
Timm Lessley
Lessley Marine, Inc.
Dba Danish Marine
152 NE Tomahawk Island Drive
image002.pngPortland Oregon

45 36.257’N
122 39.889’W

Timm@DanishMarineCo.com
www.DanishMarineCo.com

_______________________________

And there we are!
More rudder lore. Elsewhere on this site there is a picture that I recall of a red E-35-2, fitted with a rudder that looks just like the "Cal 40 blade" Grizz' Olson 34.

Regards,
Loren

ps: full disclosure: Timm's yard has done good quality work on our Olson

 

[CTOlsen]

New rudder

I went through the same debate you talk to. I opted to replace the whole rudder; post and foil and start from scratch. There is the potential for some stress corrosion cracking in the original 304 posts, so for the extra~ $500, I went with a completely new rudder.

I worked with the folks (one guy actually) at Foss and had a modified Schumaker design. I got a higher aspect ration blade, that is about 6" longer. Absolutely the way to go; Fewer roundups, great control.

Here's the picture from 2012.
(also an Olsen).

Also, made a comparison shot for the PHRF folks: