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1974 35 II modified keel

admirals barge

Member III
I spotted this Ericson in the yard getting its bottom painted. of course I had to stop and take a look. her hull was yellow but what caught my eye was the modified keel. the guy painting the boat said the last owner used to race and the keel helped and also made her more controllable when backing. I did notice the 3 bladed prop. interesting I thought. I thought I would share it with you....keel.jpg

smooth sailing
greg
 

PDX

Member III
Thanks for sharing this.

It looks like they attempted to create an elliptical shape in the trailing edge. I wonder how their end result fits with NACA foil guidelines? A common NACA taper used in underwater boat foils has the maximum chord width well forward followed by a straight, sharp taper aft. And both the taper in the cross section and the rake angle of the leading edge are supposed to be determined by the chord length.

In creating the elliptical trailing edge this owner has not only extended the chord length (over what was original) but has also created what appears to be a bulge in the cross section well aft. Its almost looks like the keel cross section has been transformed from a NACA section into a bulb. I'd be interested to know how it sails (that someone who has gone to the trouble and expense of such a radical redesign says "It helps." isn't conclusive for me). I don't doubt it improves the backing under power.
 

bgary

Advanced Beginner
Blogs Author
Interesting.

Did he indicate whether any material had been added or shaped in the main body of the keel?

To the casual eye, it looks possible that "just" the lower-aft corner was rounded and shaped, would be interested in knowing if it was more involved than that.
 

PDX

Member III
Yeah, its hard to know from the picture, but to my eye the bulge looks like it goes all the way to the left edge of the screen. I suppose its possible he was trying to create a bulb and that the bulge is close to the bottom of the keel rather than the mid-point as I had initially thought. On my boat (1968 E-30 so smaller boat than E-35) the keel is 40 inches from top to bottom. Had assumed the E-35's keel was at least as deep, but I only know E-35-II bottoms from pictures. Have never seen one out of the water.
 

admirals barge

Member III
modified keel

the rest of the keel is a standard 35 II keel its just the back of the keel was modified . the back of the keel feathers down to about a 1/2 inch. ....tom the new owner looks in on this forum perhaps he can tell us more if he reads the thread..
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
the rest of the keel is a standard 35 II keel its just the back of the keel was modified . the back of the keel feathers down to about a 1/2 inch. ....tom the new owner looks in on this forum perhaps he can tell us more if he reads the thread..

I have seen a picture of a 35-2 with the newer elliptical rudder change, but never one with any keel change.

It would be interesting to view the plan/drawing for the change that was made and actually hear from someone that had sailed it before and after.
That's the sort of glass work that can cost a lot of hours, add some wetted area, and change the center of lateral plane.
Unless it were done by Bruce King, I would sure be reluctant to do something like that.

From another perspective, having viewed a late model Beneteau of similar size in the yard recently, the hull of the 70's E-35-2 with it's internal ballast looks absolutely Faster (!). The really FAT cast iron keel on the Ben. had huge amounts of wetted surface and frontal area.

LB
 
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