Plastic Classic Forum

I pulled my rudder off and only had a tape measure to measure the shaft size. It look like it about 15/16 am I reading that correct form those that have replaced there’s before? I looked in mcmasters catalog and there is stainless shaft available in 15/16 6 ft lengths. I’ll need another foot or so added to that to make it all the way down to the bottom of the false keel. Looks like on the pics of the rudders that people have built on here have the stainless straps that wrap around the shaft and on to the plywood rudder would that be a good spot to weld the two pieces together for adding the extra length shaft together? Your thoughts? Would be greatly appreciated
I’m not very good at explaining things in writing but maybe Yao all can make some since out if this post question

I found an older post that James confirmed that Tritons have an 1” rudder shaft thanks.

Straps that bend around the rudder seem like they'd be strongest, followed by straps welded outside in pairs. The weakest is a single strap welded on the inside centerline. Outside straps mean the rudder is more easily installed and replaced later. It would help with drags turbulence and ease of cleaning bottom growth if you set the straps flush but that weakens the attachment somewhat. Even so, when I redo my rudder I will either use outside flush straps or inside straps. It you put them inside you can add as many as you want so that it becomes just as strong. Depending on where the boat is sitting you would need to dig a hole for clearance to install/remove a pre-made rudder in order to get the top of the shaft to clear the shaft hole in the hull.

Hey James did you order your shaft with the key way already cut or did you have it cut afterwards?
Mcmasters has 1 inch shafts with keyway already cut into the shaft. The shaft with keyway cut is a little pricey 352 dollars for 72” I’m sure you would have to have a machine shop cut the keyway and that’s going to be an expense of labor so with your past experience what’s the best rout to take on this.
One more question if you put a rudder shoe on the bottom custom built and a solid shat from top to bottom you don’t need any in the middle would you? Al least from the pitchers of osprey it doesn’t look like any where used other that the shoe on the bottom?

I didn't order any parts yet, just thinking ahead to doing that job one day. I didn't realize that MCMasters had so many stainless shafts and keyway options. You need to match the keyway size (1/4"?) and location fore or aft to the rudderhead/tiller strap combo you will use whether it's original, Edson, or Spartan Marine. The originals are usually too worn at the pivot bolt holes by this time. If you have a local metal fab shop that can supply the shaft and/or cut the keyway, call them for prices - could be cheaper. I guess it's easier to have the keyway cut first before welding straps.
Yes, I'd consider adding a shoe and skipping the pintles/gudgeons as on the Triton Osprey video. I didn't do that job but when I do my own boat I'll probably go that way. You may need to strengthen and improve the upper shaft bushing and fiberglass in the cockpit and/or maybe add one where the shaft goes through the hull . I'll be interested to see what you come up with.

Adding to this thread. I have my rudder off at this point. Pintles and gudgeons look good (see picture) but the rudder post less so. Lots of pink looks like significant electrolysis. Looking over material choices for the job. I’d prefer to do a bronze post with tabs wrapping around the rudder, but it’s not clear I c as n source Si bronze bar stock. The yard is recommending stainless but I’m concerned about corroding my bronze components. I’d appreciate any thoughts.

Hans

Bronze and stainless should be no problem together because they are close on the galvanic scale. Note that bronze props are common on stainless shafts as well as stainless keys.

I see your gudgeons are take-apart type, which makes it easier. Did they have bronze bolts or peened pins of some type and can you share the steps you had to take for the rudder removal?

Did you sand the bronze shaft to see if there is good metal under the surface corrosion and maybe it could be reused? Have you researched how to weld or braze bronze tabs to a bronze shaft. I think the reason it was not originally done that way and they used a relatively weak system of screws, bolts and pins going through the narrow shaft is because brazing was not any stronger. Considering all the issues, I agree with the yard that stainless is a more practical choice even if its underwater life is less than bronze.

The gudgeons were fastened together with 1/4-20 bronze flat head machine screws. Three screws to the gudgeon-two through the deadwood and one holding the split collar together around the pintles.

Removal was accomplished by first removing the top bushing then pulling the fasteners from the gudgeons. The top bushing was seized in place and had to be split off. This was the real pain of the job. Then I was able to drop the rudder. I’d planned ahead and had the yard block the boat for this.

One interesting thing I found was another bushing about halfway down my rudder tube. Never seen that before.

I haven’t sanded down to see how the parent material is doing. Thanks for the suggestion I’ll do that today

Ok rudder post is off. I had to drill out the three fastners but I might have enough meat left to get them off with vise grips. Electrolysis is bad enough that I will replace. My plan at this point is to go with stainless.

Ok I got the new rudder post back from the shop. Very strong! I needed to fair the leading edge a bit to make everything fit together. I’m
Working on bushings for the gudgeons and hope to have it all together tomorrow.