Rudder Repair Suggestions for an Offshore 33

[forsailbyowner]

Ive finally taken possession of my next project boat, an Offshore 33. The first and most pressing issue is the rudder is snapped off cleanly about halfway down. So Im pondering my options and looking for some input. The ruddder has two bearings , the upper and a skeg mounted one about 8-10" below the hull There doesnt appear to be any damage to the rudder post. Wondering just how much structure is added by the foam core, and if I dug some out,foamed and shaped the lower part and added adequate glass to the whole works if Im headed in the right direction or in err. Thanks in advance for suggestions.

[CDunc]

The foam is there mostly to keep the skins apart, this makes the panel stiff. The core also helps in sheer along the axis. Think of a rectangular steel "box" beam. More importantly is the ends (web). The stresses from the top skin is transfered to the bottom skin here.

[daddle]

It might be simpler to rebuild the whole rudder up from the existing post. But you can certainly glass on a new lower half. What was said above: the continuity of the glass is what will hold the rudder together. Discontinuities in otherwise solid foam do not affect the strength in any way. You'll want to make the joint with as tall a scarf joint as practical. Match the 'glass layup thickness. The overlap should be carefully ground to an overlap of at least several inches. This is not an easy 'glass project. The end result should be straight, fair, and have the same foil section as the original piece.

[forsailbyowner]

Heres more on what ive come up with. Im thinking of digging out what foam I can get to and building a waxed box around the lower end. While inverted pour box and remaining rudder full of the appropriate foam, then removing the box and fairing the foam to the original rudder shape, then glassing over the whole thing with a generous thickness of glass, then of course grind smooth prime barrier coat and bottom paint.

[Greatketch33]

Originally Posted by forsailbyowner

Heres more on what ive come up with. Im thinking of digging out what foam I can get to and building a waxed box around the lower end. While inverted pour box and remaining rudder full of the appropriate foam, then removing the box and fairing the foam to the original rudder shape, then glassing over the whole thing with a generous thickness of glass, then of course grind smooth prime barrier coat and bottom paint.

My rudder was snapped in half. The company that repaired the rudder used plastic tubes to provide a skeleton structure to bridge the two sections together then they built the rudder with liquid foam and fiber skin to finish it.

[rustypirate]

Rather than trying to mold the foam into shape it would probably be easier to shape a block of foam down to the correct profile. You should be able to get blocks of polyurethane foam at your local fibergalss suplier, or if not then you can also laminate sheets togeather to get the appropriate blank size.

[Captain Bill]

Have you considered buying a replacement rudder? There are a couple of places on line that will build you a replacement rudder. I have done a few foam and fiberglass projects myself and since I can't buy the raw materials wholesale sometimes the price from a pro isn't that much above my materials cost. Also, you would not have to worry about the bond quality between the old and new work. Rudder Craft and newrudders.com are the ones I know about, but there may be others. No affiliation.