Rudder swap

Mark F

Contributing Partner
Blogs Author
Has anyone swapped a rudder (same model) on a mid 70's E boat? I am modifying a same year rudder from an E27 for Lotus Flower and plan on installing it sometime in the next couple of months. Ideally I would have hauled the boat, dropped the rudder, installed the "new" rudder, checked for fit, removed the rudder, reinstalled the old rudder and splashed. But I didn't. I'm curious how consistent the fit was boat to boat in that time period.
 

Mark F

Contributing Partner
Blogs Author
Fingers crossed one more coat of barrier coat to go.
 

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Mark F

Contributing Partner
Blogs Author
Ha! No, no wipeouts. I have had an extra rudder laying around for a while. I wanted a deeper higher aspect ratio rudder in hopes that the weather helm I get on strong days might be reduced. We will see :).

Of course that assumes the wind will ever blow again.......
 
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p.gazibara

Member III
It's blowing down here in La Paz right now! Though, I don't think you would like the community here too much, they close the port when it blows 15-20! Not quite that Santa Cruz mindset.

If you keep it up, you will have the only E27 I know of worthy of triple the original price tag...
 

G Kiba

Sustaining Member
Mark,
My E27 had a lot of weather helm for the first 8 years I owned it. I pulled the mast to fix a broken spreader bolt (long story). When the mast went back up, I adjusted the rake I believe to the factory 4-5" aft (via halyard measurement). The weather helm was greatly reduced! I adjusted the back and fore stay tension to rake it further aft and wow...now very little weather helm at all! Boat still rounds up in a big blow so I know I didn't go to far. I also believe the mast dimpling issue other E27 owners report is caused by too much shroud tension. My mast and spreader brackets are original and no sign of damage to either (except a new bolt). In 15 to 18 knots the lee side shrouds go slack and just start to wander. Your mast is tabernacled like mine so it should be an easy thing for you to try out.

The new rudder looks very good and it's great to have a spare!

Good luck and let me know what works for you.
 

Mark F

Contributing Partner
Blogs Author
Hi Grant,

Do you have any bend in your mast at the 4"-5" aft rake? Do you tighten the backstay beyond (more aft) that 4"-5"?
 

Ian S

Member III
Hi Mark. Be fun to try a different rudder profile for performance gains, but the weather helm you are experiecing is your rig tuning and the sail /sails you carry at any given time. I have rebuilt a couple of E27 rudders over the years and Owned a 78 E27 for several years. I can assure you the boat has plenty of rudder for the hull form, displacement & and sail plan. I would also add that if you increase the rudder size you may "feel" as though you have more weather helm. not in steering angle (that should be reduced) but quite likely the helm will feel even heavier than before. Also be aware that the rudder has a slight counterbalance to it so you really have to calculate the ratio. the counter balancing is the portion fwd: of the post helping aid in steering. sorta like power steering. very common in performance aircraft control surfaces.
Lastly it would appear to me from the 27's I've worked on that the rudders were quite consistent and could most likely be swapped with out a whole lot of fanfare.

BTW Rudder looks great!

Best regards: Capt. Ian
 
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G Kiba

Sustaining Member
Maybe a slight bend back, yes. The mast cross-section is really stout! I loosen the forestay and bring tension back by tightening the backstay. I don't put a lot of tension in the stays. I have a mechanical backstay adjuster that seems to work well if the wind pipes up and I start getting oscillations. Usually downwind. Best thing about this fix is that you can try a little at a time and it doesn't cost much Worst thing is thinking about all the years of fighting that tiller or wheel! Hope you get it worked out!
 

Mark F

Contributing Partner
Blogs Author
Hi Ian,

Thanks for the input. When you rebuilt the E27 rudders did you change the profile at all?

I agree about rig tuning and amount of sail. I have my forestay loosened as much as I feel comfortable and have some aft rake. I may dig into my headsail furler (it covers the turnbuckle etc) to see if I can add something to my forestay hardware to make it longer.

I'm not too worried about a heavier helm feel - the "new" rudder has nearly the same area as the old. It is just less swept (more vertical) and higher aspect. If anything it has more area ahead of the rotation axis. The design that inspired me is the "Schumaker Cal 40" modification that people here have used to update their 1970's E boat rudders. (See below)

It's not uncommon to sail in 20-30 knots of wind here in Santa Cruz so sail trim/reefing gets tested regularly.

The rudder mod is certainly not necessary but it is a fun exercise. I should probably stop watching Boatworks Today on YouTube ;-).
 

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Ian S

Member III
Hi Mark. I have never really changed the profile other than slimming the rudder up and making the entry and trailing edges sharper. I have always kept the overall camber the same. The boat is no speed demon so you need a fat high camber shape to achieve decent lift at those speeds. I find the new profile interesting and would have to think that the Foss profile has more area fwd of the post so additional balance. Any drawings of the cross sectional foil shape?
SAILS: I would also say that in 20-30 knots in a boat as light as the e27 I would be carrying 100% headsail max and have 3 reefs in the main or douse the main altogether. The IOR type designs with lapper sails usually do fine under headsail alone, you just have to experiment. I can tell you my current 90-E32-3 sails with a balanced helm in 25+ with 100-125% up front and no main. Of course point of sail makes a big difference in that choice. I can't get the main reefed down enough to keep her flat in anything above 25 kts. and even when I do reef her down it's hard to spill enough air w/o beating the hell out of the main sail. I found my 27 had a propensity to make a ton of leeway in high wind if i didn't keep her on her feet. it has a relatively shallow keel and again a really fat chord so my theory has always been I have to sail flat to get the lift I need. This is going to windward of course. I advise most E owners to have a much deeper 2nd or 3rd reef put in the main than most sail builders recommend. The boats are light and relatively tender. The E27 has an SA/D of 14.7 so not as tender (theoretically as the 32) with an SA/D of closer to 18.
I also find it interesting that the Foss profile uses an elliptical trailing edge since the trend has gone full circle back to straight plumb trailing edges. Please keep us posted on your take as to how the new rudder performs. One more thing regarding sails. The depth of camber and where the max draft is located in the sail has a major impact in achieving helm balance. Older Dacron / deep drafted sails have a major effect on heeling moment. Looks like your doing nice work so again keep us posted on what you think. There are ton of older E-27's out there and in my experience can affirm that many rudders are water logged and or delaminated.

Best regards: Capt. Ian
 

Mark F

Contributing Partner
Blogs Author
The root (?) of the rudder fit perfectly against the hull. The shaft was not a perfect fit, it was 1/2" shorter than the original so the holes for the quadrant and tiller head didn't line up. I ended up having the quadrant machined so it would drop down along the shaft and allow the bolts to line up with the shaft holes. I splash today...
 

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Mark F

Contributing Partner
Blogs Author
I'm liking the rudder mod. I finally got to sail in more than 6knots of wind yesterday and the amount of rudder deflection required is definitely reduced. The old rudder was fine as far as responsiveness but the new rudder is quicker to respond. The wind was only in the 10-15 knot range so I am still looking forward to strong wind results...
 

Mark F

Contributing Partner
Blogs Author
I really like the rudder modification. Got out in some solid 30 knot stuff yesterday and the helm control is quite good!
 

Mark F

Contributing Partner
Blogs Author
Hi Pajo,

These observations are in strong conditions - 20+knts and 30+knts.

Upwind I am pointing higher and sailing faster (1knt). I was surprised to see the increase in speed to weather. Close hauled in strong wind/steep wind chop steering is easier with less helm pressure and less helm movement.

Beam reach is easier with the same less helm pressure/movement. I don't think I'm going any faster.

Broad reach with quartering seas is similar with regard to action needed at the helm but what I really like is being able to easily maneuver the boat where I want on waves. It feels like a different boat.

In light winds I am not seeing as much difference at the helm but hard on the wind I am finding it harder to balance the helm and sails. If I fall off to a close reach trim locks in fine. I'll have to play around with the light upwind stuff.
 
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