Idasailor replacement rudder.

[trapp]

I was thinking about replacing my stock rudder with an Idasailor "foiled" rudder and I was wondering if anyone else had any experience with them... improved performance, ease of installation, etc...?

[CaptK]

trapp -

Full disclosure - I worked with Joel to develop those. He was already in business making aftermarket products for sailors. We built on what I had already developed, and, with better materials and his production capabilities, what resulted is a superior product to what I would have been able to produce in many aspects. I recieve no remuneration from him, or from sales of the foiled blades. Nor do I own any stock in IdaSailor. I was allowed to keep our final pre-production prototype blade.

That said, my experience with the foiled rudder blade is all positive.

Installation is a simple matter of removing the pivot bolt on your current rudder, and swapping the old blade out with the new one. Onshore, it *might* take you 2 minutes. Can't get much simpler than that. The aluminum "spine" of Joels rudder (to which the HDPE foil is attached) is a plate of the same thickness as the stock Com-Pac rudder blade.

The foiled blade shape improves performance across the board. One reason why - water is 900 times thicker than air, and your boat has to push through that medium. Any enhancement you can do to the underwater part of your boat will have a large effect on how the boat performs.

The stock, flat-plate rudder actually *takes away* from the hulls performance as soon as it is deflected perhaps 3-5 degrees away from the straight-line hydrodynamic flow of water flowing past it (the angle between where the blade is pointed and the actual water flow is the "angle of attack"). This is due to turbulence created by it's inefficient flat shape and blunt leading edge. This turbulence is drag, pure and simple, that slows your boat down, while making the rudder less effective.

In contrast, the foiled rudder probably won't have a bad effect until it is deflected maybe 10 times that amount. This is due to it's shape being a NACA foil designed by engineers to have the most efficient shape possible for producing lift (making the rudder more effective) through the widest range of angles of attack. To some degree, the rudders foil shape also acts as a mini "keel", providing additional lateral resistance when sailing to windward.

Another design factor we put in was to shift the leading edge of the rudder forward a couple of inches. This puts more of the rudders surface area forward of the pivot point, making for less of a weather helm feel at the tiller. We also increased slightly the overall surface area of the rudder, making it more powerful.

The materials they are constructed of (aluminum and HDPE (Plastic #2)) are almost 0 maintenance. If some plant or animal growth, or other water scum gets on the blade, it can be scraped or scrubbed off easily. Stains disappear with a bit of bleach. It needs no paint. There are no additional electrolytic metals beyond that which the boat was originally designed with.

I highly recommend them. I should also add that the price Joel is selling them at is much cheaper than what I would have been able to, making them of fiberglass and other compocite materials. Also, Joel is very good with his customer support, and the blades have a very good warranty.

That pretty much covers it.

[Craig Weis]

Say salors, I put a I.S. RUDDER on the stern of my CP-19. And I'm glad I did that!

It's like power steering was added to the tiller. A lot less effort. Without the foiled rudder I needed two hands and a strong back just to hold on to the tiller, now I think I can hang onto the ragged edge of being in control and loosing control, read weatherhelming, a little longer.

It sounds different too when cutting through the water at speed.
skip.

[Craig Weis]

CaptK
I agree best thing since buttered toast. I don't do butter [actually].

Off~set the centerline balances the rudder, giving the 'power steering' feel to the tiller.

My boat [C-P 19] had always glided up to the dock and was very difficult to slow down. She just keeps crawling along at almost zero speed. One can use the tiller/rudder to 'power her' up to the dock, as in  Skulling. Thank you NASA; what a nice curved hull and stubby keel she has. With the foiled rudder she now is MORE difficult to slow down. AND I LIKE THAT  :!:

I installed my rudder [after appling three coats of Mother's automotive wax] while hanging over the transom. And had the stern pulpit, outboard motor, transom ladder, coils of lines on the pulpit, tiller, and other things blocking my way.

This is funny. :wink:  BUT the main problem was getting the bolt holes lined up while the new rudder wanted to float away!...which is why this foiled rudder is about two pounds heavier on land than the aluminium plate and about four pounds lighter in the water than the aluminium plate. That's good. Less weight in the stern. And compressing your lungs while hanging over the side is not conducive to being able to breath or see the holes to get them lined up well enough to push the bolt through all three holes. It took me about a half hour to install the damn thing. "That's why they call me 'DEAD EYE"
LMAO.   skip.

[lbiguy]

Planning on using the Idasailor in salty (bay) water on a 23.  And leaving the rudder  pinned down.

BUT the article on barnacles in Practical Sailor suggests that those buggers will attach to anything.  So --  painting with a plastic adhering paint and then anti-fouling has been suggested.

Anyone left an Idasailor in salt for a couple months?

Have had an Idasailor on still-for-sale 19 but kept it out of the bay when sailing.  Appreciate any thoughts.  

R

[Ljmeisner]

I still have the original aluminum rudder, which pivots up so it's (barely) out of the water when I'm not sailing.  Not sure whether or not Ida Sailor has that feature.  It would be a shame if it didn't, since it sounds like such a great addition.

[jaguaretype]

Larry, the Ida Sailor rudder also pivots out of the water.  Mine is easy to pivot up and secure when the 23 D is not in use.  Jay.

[pbrenton]

Just a thought; Has anyone tried shaping the stock aluminum rudder?  I was looking a tthe pitting on mine (prior owner was not that good about changing the zinc) and was thinking that as long as I had the grinder out with the right wheel, why not take the right angles off the leading and trailing edges of the rudder.

Not as good as the Idasailor's wing shape, but since an outbaord engine needs to be acquired this year, the rudder is not in the budget (maybe I'd have to spend just as much on grinder wheels to do that much to the stock rudder?).

Pete

[Craig Weis]

pbrenton
Well if one had giant cans of Bondo I supose a foil of sorts could be shaped. Material I would think will have to be added little by little and built up. Or use wood layers worked down and shaped.  

We have a weed problem in the Sturgeon Bay 'cut' between Green Bay and Lake Michigan. I often dreamed of grinding and honeing my aluminuim rudder as to slice through the thicket. Though I'm running a Ida Sailor rudder. Love it!  skip

[Steve]

Hi All,
Just got my new Idasailor rudder. It looks better than I thought. I'll let you know how works in about two weeks!
Steve

[Craig Weis]

I want to know...

1~... if you think that the effort to steer the boat is less, meaning...is it like 'power steering' on the tiller? Some of this IdaSailor rudder is in front of the vertical centerline where the tiller bolts-up.

2~...does the rudder 'oscillate' ever-so-slightly, felt through the tiller?

3~...Can you hear the rudder burble through the water with a different sound than normal with the flat plate? You'll have to go to 'noise discipline' for this one.

...for me it's yes for all three. And I think my boat glides a wee bit more needing less effort to move.

Just like a car, boat, train or aeroplane...effort squares as speed doubles. Simple physiques.

That's why the car uses more petro the faster she moves. Or as we use to tell the skipper,
"The angle of the dangle is equal to the mass of the ass." Can I say that?  :oops: skip

[Steve]

Installed my new idasailor rudder about three weeks ago. I wanted to get a few days (different conditions)on the water before I posted my review. The rudder performs as advertised. The boat is scull-able a slow speeds and remains in control(relative) when over-canvased. I was most interested in the weather helm reduction. I was able to keep full sails up longer in winds greater than 15kts. The old rudder acted like a big brake when close hauled in wind greater than 15 apparent. I believe this brake effect actually increased heel (spill more air) because the boat couldn't covert the excess wind energy into forward motion. The new rudder actually provides lift to the stern and reduces weather helm in higher wind speeds. This also seems to help the boat point a little higher.  The rudder is a great upgrade.

Steve
CP23/III

[Tim Gardner]

I decided to use this thread to report on my conversion to the IDA rudder I recently bought from Steve Brown ( who incidentally still has a newish 155 Genny for sale - plug, Steve, Plug).  

I want to know...

1~... if you think that the effort to steer the boat is less, meaning...is it like 'power steering' on the tiller? Some of this IdaSailor rudder is in front of the vertical centerline where the tiller bolts-up.

2~...does the rudder 'oscillate' ever-so-slightly, felt through the tiller?

3~...Can you hear the rudder burble through the water with a different sound than normal with the flat plate? You'll have to go to 'noise discipline' for this one.

...for me it's yes for all three. And I think my boat glides a wee bit more needing less effort to move.

1 - I agree  2 - Yes, but I haven't replaced my sloppy bushings yet (this week).  3 - Definite burble at the point of stall.

I really felt the difference when pinching closer to wind.  While it may be my imagination, the increased acceleration during gusts while heeling less, thrilled my inner racer and scared the Admiral less.  (I actually complimented her on her calmer demeanor during some 25-30 MPH gusts under full main and working jib.)

4.  Even though I really tightened the pivot bolt, the rudder did manage to swing aft a bit. (Discovered after backing into her slip to remove to rudder in prep for re-bushing.)

5.  The Admiral thought it was prettier (verry important).

Just a few thoughts - more later on .

TG

[curtisv]

I decided to use this thread to report on my conversion to the IDA rudder I recently bought from Steve Brown ( who incidentally still has a newish 155 Genny for sale - plug, Steve, Plug).  

I want to know...

1~... if you think that the effort to steer the boat is less, meaning...is it like 'power steering' on the tiller? Some of this IdaSailor rudder is in front of the vertical centerline where the tiller bolts-up.

2~...does the rudder 'oscillate' ever-so-slightly, felt through the tiller?

3~...Can you hear the rudder burble through the water with a different sound than normal with the flat plate? You'll have to go to 'noise discipline' for this one.

...for me it's yes for all three. And I think my boat glides a wee bit more needing less effort to move.

1 - I agree  2 - Yes, but I haven't replaced my sloppy bushings yet (this week).  3 - Definite burble at the point of stall.

I really felt the difference when pinching closer to wind.  While it may be my imagination, the increased acceleration during gusts while heeling less, thrilled my inner racer and scared the Admiral less.  (I actually complimented her on her calmer demeanor during some 25-30 MPH gusts under full main and working jib.)

4.  Even though I really tightened the pivot bolt, the rudder did manage to swing aft a bit. (Discovered after backing into her slip to remove to rudder in prep for re-bushing.)

5.  The Admiral thought it was prettier (verry important).

Just a few thoughts - more later on .

TG

Tim,

1.  A little yes.  Less tiller force when the wind picks up a bit.

2.  Only occasionally and now barely noticable since I replaced the bushings

3.  Nope.  Maybe your sails are not balanced.  I changed things a bit on my CP23.  http://www.faster-light.net/remote-access/projects_S_R.html#2 and http://www.faster-light.net/remote-access/projects_S_S.html#1

4.  I have a bungie for this (which thanks for reminding me is due for replacement)  [url][http://www.faster-light.net/remote-access/projects_S_R.html#6/url]

5.  No comments form the Admiral on asthetics


The CP23 has a bit more weather helm than it should as the wind picks up.  To some extent the IDA rudder is fixing the symptom, the need to get a lot of rudder force to compensate.  A smaller headsail helps when the wind picks up.  A big genoa on a roller furler doesn't count as a smaller headsail since it will have terrible shape and cause excessive heel for the forward force it creates when furled too much.  If you have a working jib, then reef the main first to keep a good balance and cut down on excessive heel.  Too much weather helm is the problem.  The bowsprit helps.  Raking the mast forward helps a bit.  A traveller may help by making it possible to flatten the mail and keep it eased a bit for better sail balance (haven't tried that one yet, though the vang helps).

If your rudder is gurgling your sails are quite out of balance and you are creating a lot of drag with the rudder.

Curtis

[curtisv]

Now here is a balanced rig.  Note the two fingers on the tiller.



That is Matt on his Wianno.  Mast raked forward a bit and the lightest helm I've ever seen.

Curtis