Sloppy Rudder Stock - 37CC

[ccarmody]

Hauled her today and noticed quite the abrasion on the starboard side of the hull by the rudder (see pic). It's worn through the paint, gel coat and now down to the fiberglass - anyone seen this before? There is some play in the bottom of the rudder now, maybe 1/8 at the top and 3/4" at the bottom. I'm going to take the quadrant off tomorrow and work on dropping the rudder to get a feel for what I'm up against but anyone gone through this?

 

[ccarmody]

Sorry-- I should have rotated this photo prior to posting, as the left-hand side is actually the top--thx!

 

[SailingCal21]

Not familiar with the construction of the 37's rudder tube, but it's hard to believe that there would be that much slop in it to allow the kind of movement that you're showing. From the photo, it looks like the top of the rudder is somewhat swollen. Perhaps the issue is with the rudder swelling or delaminating in that area.

Please keep us posted on your findings.

 

[ccarmody]

Pulled the rudder today

Went ahead and bit the bullet and pulled the rudder - no signs of delamination or other serious damage or water intrusion to the rudder. Rudder stock appears true and not bent. It appears there was never any type of bearing arrangement in the cylinder for the rudder stock, there is just a fiberglass "doughnut" epoxied in the bottom of the hull and a fiberglass tube/cylinder mated to it to receive the rudder stock - all held in at the top by steering disc through-bolted to the stock.

Some others in the yard have suggested two approaches:
1) shim up with some delrin inserts on re-assembly
2) mix some West 423 graphite w/ some epoxy and give the tube a thin coat, add another delrin washer at the base of the rudder stock to space it out enough to prevent the abrasion against the hull

 

[ccarmody]

Re: Pulled the rudder today

 

[jibes138]

Just a thought, you might want to coat the rudder stock with some kind of release agent, then use some graphite epoxy mix to fill the gap and let it harden. Then remove the rudder stock and remove the release agent so you have a small amount of clearance for free rotation. There should be a grease fitting on the rudder tube to keep it lubricated.

 

[SailingCal21]

Mine has a similar construction. Was there evidence of grease in the tube when you pulled it?

Thanks Jibes, it's been a while since I greased my rudder tube. Gonna add that to the list this spring.

 

[ccarmody]

There is a grease fitting and there was some grease in the tube (see crude diagram below). I'm still trying to decide what direction to take - the release agent sounds good, I'm just not sure how much epoxy/graphite I could even get in there to begin with. It was/is a super tight fit (but there's obviously play somewhere). When the bottom of the rudder was wiggled, there was basically no movement at the disc so I'm assume the worn area is at the base of the tube. The delrin washers are right on tolerance-wise with zero wear.

 

[Richard9563]

I thought I had some binding last year so we ended up dropping the rudder, cleaning & lubing the tube. Totally missed the grease fitting. Seems to be working fine though. Good pics. I'll watch mine closer now.

 

[SailingCal21]

Yes, good drawing. May want to change the "Steering Disc" to Steering "Quadrant". Otherwise spot on.

 

[ccarmody]

I've always heard the term quadrant but it's my impression now that refers to the more typical arrangement of 1/4 of a circle steering system - this is in fact a full 360 deg circle/disc, about 2' in diameter.

 

[ccarmody]

What do you guys have on the 34/35's, a full disc or 1/4? I've never been inside but from the outside they're obvious family.

 

[SailingCal21]

My bad, thought that your 37 would be the same system as the 34. Karma has an Edson wire chain system with a quadrant.

 

[rajhnsn]

Quadrant, cable no chain.

 

[DannyS]

I've always called mine a quadrant though it is a full disk. Mine is cable to a short length of chain in the pedestal over the gear attached to the wheel.

 

[ccarmody]

Sorry, didn't mean to start up a terminology discussion - looks like Nigel Calder and Don Casey call it a "radial" drive, wheel, disc or... whatever... sloppy rudder is what I've got.

On further cleaning and disassembly turns out there's a hairline crack in the top where there was minor water incursion. Many drill holes later I've isolated it to a 1x2" area in the top and it's now draining and heated by a halogen shop lamp.

I took a micrometer to the delrin bushings and there's .013" diff from side to side (vertical thickness), still need to do my math to see the slop is at 5' due to that. Of more interest is after some acetone and scrubiing treatment to the rudder stock there's definitely wear at the base of the stock about 1" above the rudder, right where the collar is at the base of the receiving cylinder.. looks like nobody used that grease fitting over the years, including me :cry:

Going to take some measurements of the diameter of the rudder stock at that point now to see what I'm dealing with but that appears to be the real source of the play (See below)

 

[rajhnsn]

I stand corrected. Thought mine was a quadrant but it is actually a full wheel, disc or whatever we want to call it. I think I will add some grease to my fittings.

 

[SailingCal21]

ccarmody, can't see your last image. Do suppose that the crack at the top of the tube is from the rudder striking something and knocking the whole assembly out of alignment to cause the excessive wear?

From pics of the 37 on the hard, it looks like the rudder is reasonably protected by the keel so perhaps that's a bit of a stretch.

 

[ccarmody]

Weeping Rudder

It doesn't look like the damage to the stock is via impact but instead just friction wear. The crack is on the top, looks like just adhesion let go in one section. My attention has turned to the rudder itself vs. the stock, 50+ holes drilled at this point. There were 3 small areas that held water. Fortunately everything drained crystal clear without any sign of corrosion. I let it sit on the shop lamp for two nights after the last drips. The only delamination was a 3x5 section near the trailing edge. I've followed the protocol and injected the STB side with thickened epoxy as per Don Casey's instructions.

I'll let that cure and then to the port side, then a couple coats of interlux 2000e.

 

[SailingCal21]

Pay close attention to the interface between the rudder stock and the rudder. It's generally considered that is where the water gets into the rudder. There's been a considerable amount of discussion about that on previous post.

On Karma the webbing of the rudder is composed of several smaller stainless tubes that are attached to the stock. The rudder is composed of 8# closed cell foam. I filled the tubes with closed cell foam so there would be no place for the water to fill into.

Photos posted at this link:
https://groups.yahoo.com/neo/groups/odayowners/photos/albums/1499613179