I did it on a Catalina 309. Misaligned rudder tube made it impossible to use new bearings once the original bearings failed very prematurely. I either had to cut out and reinstall a rudder tube or try the epoxy and graphite trick.
Not sure if my experience on the 309 transfers to your 30. The 309 uses a couple of Marelon bearings, one at the top and one at the bottom. Aside from the bearings, the clearance between the rudder shaft and the tube is around a quarter inch or so.
For the most part, I followed the instructions from West Systems.
Dropping the rudder was easy. There wasn't enough vertical clearance for it to exit the tube, so I dug a hole under the rudder. Marina soil was so hard packed it required a pick to break through it.
As you mentioned, the shaft gets waxed. Prior to waxing, I used various grits of sandpaper on it to get it as smooth as possible. There were a couple of burrs that had to be leveled, and a couple of small gouges and scratches that needed to be filled. You can imagine that if you have any indentations in the shaft, they'll get filled with your epoxy and cause problems when you turn the rudder. I filled the indentations with thickened epoxy and sanded smooth. I wonder if JB Weld would have worked. On the shaft, I probably went from around 400 grit, up to 1200 or so. Followed by about three coats of wax. I used Collonite Fleet Wax. I figured I didn't want to skimp on the wax, as it would be a catastrophe to not be able to free the rudder once the epoxy cures.
The entire rudder tube on my boat was about two feet, and I didn't attempt to fill the entire tube. I did about 6 or 8 inches at the top of the tube, and about the same at the bottom of the tube. I figured that would give me a little greater bearing surface that the original bearings provided. In retrospect, I probably could have done more.
Once your rudder shaft is totally prepped and you hang it again from the top pivot point, you'll need to make sure you shim it as needed where it exits the tube at the bottom so you have equidistance between the shaft and the tube all around. Of course, you'll have to seal around the bottom so your epoxy doesn't run out.
Because I didn't want to fill the entire tube with epoxy, I made a cardboard donut that would create a dam between the shaft and the rudder tube. I cut a slit in it, put around the shaft (with the shaft installed), taped the donut closed, and pushed it down into the tube about 6 or 8 inches with a long screwdriver. When I added the epoxy at the top of the tube, it could only flow as far as the cardboard, creating a top bearing. At the bottom of the tube, I drilled holes around the tube, 8" from the bottom, into which I injected the epoxy. That created another 8" bearing. I figured the cardboard donut for the top bearing would just decay over time. If I were to do it over, I think I would fill the entire void around the shaft from top to bottom. I was probably hesitant because I couldn't find much information on the net from people who have used the epoxy technique on their rudder.
Have plenty of epoxy on hand. Have an assistant. I toughed it out solo, and that was a mistake. You're dealing with runny, black epoxy in a confined workspace. Someone to hand you stuff when you need it is invaluable. Obviously, have sufficient materials, and mixing pots, etc. on hand. Rubber gloves...you knew that. The West syringes worked very well for getting the epoxy where it needed to go.
I recall that they recommend drilling holes in the side of the rudder tube, into which you squirt the epoxy. Maybe it would be possible to put it all in from the top, but drilling holes and working from the bottom, and taping over the holes as you work your way up would ensure that you get the best coverage. Even if there are some voids, as long as you do most of it you're okay. Again, do plenty. My steering may have been a little stiff when sailing close hauled.
I mixed my epoxy exactly per West's instructions, particularly with regard to the amount of powdered graphite I added. After all, the graphite's the key to this technique. And, I gave the epoxy plenty of time to cure before attempting to free the rudder. I don't want to imagine the mess that could be created if you tried to turn the rudder too early. Patience.
After the proper cure time (and a little extra to be sure), I stood under the boat, crossed my fingers, eyes, and toes, grasped the rudder fore and aft, and gave it a twist. It snapped free with just moderate pressure, and was smooth as silk as I turned it back and forth.
I had been apprehensive about doing this repair, but it turned out to be an inexpensive and not terribly difficult repair.
