Rudder length on shoal draft 33s

Paul F · Dec 19, 2010

Yes, the rudder was modified in two ways. 7" was cut from the bottom of the rudder and 7" was added to the tail-end of the rudder making a more square rudder shape. These changes added surface and this configuration has worked very well for over 6 years. The boat backs very well as an added benefit of the expanded rudder surface. There have been no drawbacks with this change in rudder shape.

Terry2821 · Dec 28, 2010

I built my own rudder for my H33 shoal draft. When I got the boat it had a bent/broken rudder due to the fact that the rudder was the same depth as the keel. I built mine 3" shorter but 7" longer. I built mine to an airfoil spec of which number I cannot recall (but can look it up). I have no point of reference to how well it sailed before but I can tell you it sure as heck sails pretty well. Most of my sailing friends get on the boat...take one look at the wind indicator and with puzzled faces say "how can that be??"

sandpiper10471 · Jan 3, 2011

I would be hesitant to add to the depth as it tremendously adds to the forces applied to the bearings and support structure inside the boat through leverage. Built a very narrow but deep high performance rudder for a racing dinghy once and while it felt like power steering and lots of benefits upwind, I ripped the transom off her on my first planing wave downwind. Too much leverage.

jibseaman · Jan 16, 2011

So should I do it? I am out of the water and have a bent rudder. I'm tempted to shorten the rudder 6'", leave the bent shaft and see how she goes. I may be pulling her for other reasons soon anyway. So what do you all think?

sandpiper10471 · Jan 16, 2011

Oh man, Jibseaman, bent shaft? Straighten the shaft. It is not that hard to drop the rudder on the 33 but you might have to dig a bit of a hole for it to land in. Sometimes shafts can be straightened in place. Depends on the bend. And I wouldn't hesitate chopping a few inches off the bottom. Six could be a bit much unless you add some lateral area to the leading and/or trailing edges.

jibseaman · Jan 17, 2011

Thanks Sandpiper, The steering pully that bolts to the rudder shaft and holds the steering cables is stuck. The stainless 4" bolts are frozen in the aliminium wheel any suggestions on that one? I think I'll only cut 4" off the bottom then.

Ed Schenck · Jan 17, 2011

Must be a salt water boat. My radial wheel came right off after thirty years. Two bolts clamp the two halves together and one thru the post. You could try soaking for a couple days in WD40. But can't you just bust them with two large ratchets or breaker bars? Be sure to loosen and remove cables first. And you really do want to straighten the post. A good boat yard did mine. NO heat.

Steve Dion · Jan 17, 2011

If you can get a sawzall in there you can cut the bolt off.

DougonOrion · Jan 19, 2011

I pulled my radial wheel off my '78 h33 last year. Had same problem with bolts. Forced one off, the other broke. That got it off. I extracted broken bolts, drilled through holes, and now have two stainless through bolts. That way, in another 30 years from now, the next owner will have no problem removing them

Also, i found that the upper rudder bearing (a flange mount ball bearing) was totally rusted. I ended up replacing in with a food-grade stainless bearing from mcmaster, expensive at ~$300, but i doubt i'll have problems as long as i own the boat.

SamLust · Jan 20, 2011

Jibseaman: Yes, of course you should do it. That way the rest of us can learn from your experience. Notice I didn't say mistakes? I'm particularly interested in how you take care of the bottom of the rudder. I haven't come up with a method of glassing over it than I'm happy with. Take pictures. And get it done befor the beginning of the New jersey sailing season so I know whether or not to do it to mine before it's time to go back in the water.

As far as straightening the rudder; If it's not bent too badly you can do it in place with the boat out of the water. I used a heavy ratcheting load strap wrapped between the keel and the rudder. Crank down on it and the shaft should come back. My hull has had no problem taking the forces. I actually straightened mine once by backing into a sand bank. No problem.

Ed Schenck · Jan 20, 2011

That's right Sam. The rudders are built with a kind of frame. Then it is filled with the foam and a skin put over the whole thing. When they straightened and rebuilt my rudder they reused that frame. But they put in a new and better foam and a new skin. When you shorten a Foss Foam rudder you are cutting off the frame bottom. Wish I had a picture before they filled it.

SamLust · Jan 20, 2011

Looking at Ed's picture has gotten me thinking. Might be that what's needed is th shorten by about 4 to 6 inches, add about 6 inches aft, and then add some to the forward edge below the level of the propeller. That might retain the easy balance it has stock. jibseaman; can you get that done and report back to us on your findings by mid March? That would give me time to get it done if it works for you. If it doesn't I'll be happy to offer encouraging words.

Technique for loosening stuck bolts: apply heat, and spray the hot part with PB Blaster or similar penetrant. An electric heat gun is really good for this, better than flame. A few cycles usualy gets the job done. Don't go crazy with heat to the point you damage the foam or glass of the rudder. Last resort: DRILL the HEAD off the bolts. Punch dead center and use a drill bit slightly larger than the bolt diameter. Much less colateral damage than a Sawzall. Also smack the bolt heat a few good raps with the old ball peen. Helps loosen things and let it know who's boss. Use never-seize on new hardware. I use it every time I bolt metal to metal, regardless of alloy.

sandpiper10471 · Jan 20, 2011

DougonOrion: Any chance you could post a photo of that upper bearing? I don't recall having one of those on my H33.

jibseaman · Jan 20, 2011

Sam you sound like a nut! So for you I did it. skill saw 4" just like that! Cut it off last night patcghed it up today. I routed out about 1/4 " of the foamthen filled with resin and mat used wax paper to tighted it all up. Sanded then wrapped the cercumferance with woven and tucked the tail under. once again covered with wax paper to tighten and hold in place. looks like it worked great. I'll report back after i sail!

SamLust · Jan 20, 2011

jibseaman; I never stated in any of my posts that I was sane. With all the stuff i've done to this boat I couldn't be! Assuming you are successful with the rudder my delema is whether to do the cutoff with sawzall, (always a favorite) circular saw or chain saw.

DougonOrion; The rudder support bearing is a chunk of plastic, probably HDPE about 4" by 4" by an inch thick. Sounds to me like a PO got creative and installed an industrial pillow block bearing. They normally live ina greasy environment so rust is not a problem.

By the way; in place of the waxed paper try a piece of polyethylene film. The stuff they sell for cheap drop cloths. Roll it over your layup. Peel off after cure and you have a perfect slick surface.

Ed Schenck · Jan 20, 2011

BillP, about that rudder bearing on the H37C. On my boat it is an aluminum collar riding on a marble block. The block is on top of the upper shelf. I thought that I had a picture but no luck. I do have this picture of a friend's H37C as he was getting ready to install a below decks autopilot(which is in the Photo Forum). He reversed the block and bearing to keep the rudder from floating up. You can just make out the bearing and the block at the very top of the photo. The shelf is not visible.

Found better pictures in the Photo Forum. You can see the shelf and that he moved the bearing under it. Mine is reversed, on top.

sandpiper10471 · Jan 21, 2011

Thanks, Ed and Sam. I couldn't remember anything other than the poly block on the H33. Thought maybe I'd missed something. The ball bearing rig must have been a mod.

The floating up of the H37C rudder is an issue - not a big one - but a concern. I will need to construct a poly donut some time, drill and split it and install under the shelf. The odd time I have caught my dinghy painter between the top of the rudder and the bottom of the boat and there is wear in the glass work on the centreline where the rudder sometimes rubs. Just another thing to fix.

Rudder length on shoal draft 33s

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