Rudder stock/bearing advice

[Cardo]

Right, here goes...

Our Southerly 105 that originally came with a single transom hung rudder was modified by the previous owner to twin, semi-balanced transom hung rudders.
Whilst mechanically it works, there's some details I rather wish he'd thought of during the design/build phase that clearly weren't particularly high up on his agenda!

The two rudders are held on at two points each (pintles, stocks? Don't know what to call them, so I shall henceforth refer to them as pintles). Here's a picture of one.

As you can see, the brackets on the transom and the rudder are held together by a bolt that goes through them. They're designed to allow the rudder to rise up a couple of inches if necessary to alleviate strain on the rudders when the boat takes the ground.

The problem is the bolts aren't a snug fit in the brackets on the transom, so there's some play between them. When there's back and forth tide/stream going past the rudders, they have a tendency to "knock" as they are pushed back and forth in the pintles. Our cabin is just the other side of that transom and at times this rhythmic knocking can do my head right in.

There isn't enough space to get a proper bearing in there or anything of the sort, but I was wondering whether I would be able to get a sleeve for the bolt, maybe something in nylon that would make the fit slightly more snug and cushion the knocking.
Problem is, I have no idea where I would get such a piece or whether this is even a reasonable idea.

Anyone have any thoughts, suggestions, anything?

Cheers!

 

[alahol2]

My Stag has a similar arrangement except that the rudder can rise 12" - 18". It is accomplished by using a stainless rod (10 - 12mm dia) that passes through all three gudgeons and pintles. I suspect a similar arrangement on your rudder would prevent the rudder 'rocking' on the bolt and creating the knocking noise.

 

[VicS]

Anyone have any thoughts, suggestions, anything?

Why not just use larger diameter bolts or perhaps purpose made pins to reduce the sloppiness to a minimum


You might have to enlarge all the holes so you'll almost certainly need to get all the fittings off to drill them out on a bench drilling machine using a cobalt steel drill bit.

Make sure the plain un-threaded part of the new bolts is larger in diameter than the threaded part ... There is a tendency for metric threads to be rolled rather than cut. When they do this the shank is slightly smaller than the thread. It may not apply to the sizes you will use but if it does you'll end up all sloppy again.

 

[Cardo]

Thanks for the suggestions.
Unfortunately, the boat is in the water and we're not intending to take her out for some time.

I can remove the bolts, one at a time without too much grief, but removing the fittings is a little more than I can accomplish at this time.

Any "easier" thoughts, even if short term?

 

[northwind]

Thanks for the suggestions.
Unfortunately, the boat is in the water and we're not intending to take her out for some time.

I can remove the bolts, one at a time without too much grief, but removing the fittings is a little more than I can accomplish at this time.

Any "easier" thoughts, even if short term?

You need a top hat bushing / bearing:

http://www.bpfonline.co.uk/search.asp?catid=10726

Alternatively find someone with a lathe to knock a couple up?

 

[colhel]

Thanks for the suggestions.
Unfortunately, the boat is in the water and we're not intending to take her out for some time.

I can remove the bolts, one at a time without too much grief, but removing the fittings is a little more than I can accomplish at this time.

Any "easier" thoughts, even if short term?

I owe you a favour. I'll make you some pins or bushes. Phone me if you're interseted.
looks quite a simple fix, just need to take some measurements

 

[Cardo]

I owe you a favour. I'll make you some pins or bushes. Phone me if you're interseted.
looks quite a simple fix, just need to take some measurements

Colin, thanks for the offer. Some top hat bush things like the link above seem like the right kind of thing, although the website above doesn't seem to have quite the right size for what I'm after. I shall take you up on your offer and give you a call once I've measured up the bolts and brackets.
Ta muchly.

 

[colhel]

If you want to use top hat bushes the brackets will have to be drilled and reamed, won't they? Otherwise you'll have to use a smaller diameter pin.
My (easy) suggestion is to examine the existing holes to check the worn to an oval shape and make a pin to a close fit.
The better (longer term) option would be to drill and ream the brackets to a larger size and make a bush and pin to fit.

 

[rob2]

Top-hat bushes should work fine, but to lock them in place I think you'll need to fit them with the flanges toward each other and a spacer tube to hold them in place. Otherwise when your rudder rises it will pull one out and the other as it goes down and they'll both be flopping around in the middle!

Mind you, I'd rather see a heavier fitting altogether with a substabtially larger pivot bolt/pin!

Rob