O22: Proper CB pivot play?

Feb 27, 2018
4
Oday 22 Putnam Valley NY
centerboard_pivot_wear_play_2018_1200x.jpg
I just wrote to Rudy, but haven't heard back. When I do, I'll post the answer here. Meanwhile, does anyone else have an answer to this? I've looked all around the web, and seen many different opinions:

As you can see from the picture, my O'Day 22 centerboard pivot hole is much larger than the 1" pivot. The pivot is unworn (some insignificant grooves, but the sides are straight), but it flops around in the hole. You can see how large that hole is from the light coming through. My question would be, what is proper? What was the size of the hole when it left the factory?

Some people say the play must be loose,so that the pivot does not take any of the side strain of the CB when under sail.... that the board must be able to stop against the CB slot. But I would imagine even with a much tighter tolerance than I have, the board would be able to do this, without straining the pivot.

If the hole needs to be closed a bit, I'm going to notch the sides of this hole, and rough it up. Then I'll fill it with epoxy, and re-drill it.
 

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Jun 2, 2004
1,937
Oday Day Sailer Wareham, MA
Well, the pivot hole on my DS II centerboard has very little play and pivots fine. I'd give Rudy a phone call, (508) 644-3001, he isn't a big e-mail guy (sorry to say, but also it is his busy season, everyone waits until days before they want to use their boat to order parts!). The toll cost may be well worth the one-on-one advice! I wonder if maybe that is not the original pivot pin and it is under-sized?
 
Feb 27, 2018
4
Oday 22 Putnam Valley NY
I wonder if maybe that is not the original pivot pin and it is under-sized?
Sunbird! That had not even occurred to me. Thanks much. I'll examine the hole carefully to see if there are even signs of wear. And perhaps there are clues to the proper sized pin from the wedge slots, or something like that. If the sides of the hole seem perfectly circular and unworn, perhaps someone just put in a too-small pin! Now I wish there was an easy way to know the size of the original... I certainly don't want to fill the hole before knowing for sure.

Well, the pivot hole on my DS II centerboard has very little play and pivots fine. I'd give Rudy a phone call
Rudy did write back, and told me, "Yes this should have a tight fit."

And so it will, thanks to both of you... when I do put it together. Whether I now find a larger diameter nylon rod, or fill the hole, is the only question...

Thanks again! Rich.
 
Feb 27, 2018
4
Oday 22 Putnam Valley NY
Sunbird! I just went outside and examined the pivot hole. It is very clean and round, and about 1 1/8" in diameter. This is one clue that your suggestion is correct, for one would expect a worn centerboard hole to be out-of-round (considering the board hanging down always, it should be elongated in an up and down direction, I would think).

Another clue is that my CB rod is somewhat crudely sawn off on one end... like someone did it roughly, in a hurry, with the wrong saw. This is very different than the very nice quality of finish on just about anything else on these boats.

A third clue was when I checked the online image of this arrangement (not sure where it originated, but an O22 owner here, I think)(my apologies for using the pic, and thank you), and used my graphics program to "move" the diameter of the pin to the width of the SS plate for comparison. Yes, not perfectly scientific... but since the pin in the picture if further back, and since it is very slightly elongated left to right from the angle, it should appear smaller in comparison to the wedge retaining plate... but it is still bigger. See pic:
pin_size_compare.jpg


As I said, not scientific... but from all clues I would guess the pin was replaced with a too small one (found in a hurry probably... marina shop? local hardware?), and that the pin should be 1 1/8" or thereabouts. So I'm going to order a 1 1/8" Delron or nylon (haven't decided yet which) rod on eBay, and give that a shot. I might turn a test rod on my lathe first, in wood, just to see the fit in the hole, before ordering.

Thanks much for the tips...

Edited to add: Setting up the lathe would have been over-kill... I simply wrapped my 1" pin with stiff paper until it was exactly 1 1/8" in diameter, and taped it. Then I went outside and tested it in the CB pivot hole: A perfect fit! Slid right in, with just exactly the barest amount of play one would hope for! So that is the answer... the rod was replaced, and the hole is not worn. Happy days!
 
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Feb 27, 2018
4
Oday 22 Putnam Valley NY
OK... that was the whole deal here: A previous owner substituted a (too small) 1" nylon rod for the necessary 1 1/8" diameter rod. So I bought one foot of nylon rod on eBay (for about $14 shipped to the door). It is a perfect fit. Clearly there was no perceptible wear to the CB hole... it is nice and round and smooth. With the new rod, there is just the barest amount of play... just a bit looser than a "friction fit". Here is a composite shot, from two angles:

new_centerboard_pivot_2018.jpg


I chose nylon instead of Delron, after looking up the specs of both and comparing them. While Delron is slightly stronger in shear and flex, they are both massively strong. But the nylon has better resistance to wet environments, and alkalies. It also has better wear characteristics, and is "slipperier"... if that is a word.

So now I just have to cut it to the proper length, and I'm all set. Hopefully this information will be a help to others...

Thanks again, Sunbird, for the suggestion.