26X "Mac Slap"

[pitchpolehobie]

Hi guys --- I have a new centerboard hanger that I plan on installing before my spring splash. Its more of a preventative issue and I want to inspect my CB since ve never dropped it. Has anyone tried to prevent the "Mac slap" with rubber bushings on the pivot pin to reduce the sway as done in the following video? basically 2 pieces of 10mm rubber next to the centerboard on the pivot pin inside of the hanger. Ive seen some additions on the mod section but Id prefer to stay away from those mods.

I also have the bwyachts CB dyneema line. What knot have you used to stay snug and not slip but also fit in the CB notch?



Let me know your 0.02$

[Russ]

Interesting idea. Seems like it should work.

I'm not familiar with the hanger on the X and didn't know this was a thing. The M flops around in the channel. I wonder if something like this would help with that.

[pitchpolehobie]

https://www.ebay.com/itm/375101277433

I got 60mm diam, 5mm thick and will try to double up on each side. Will drill hole for pivot pin so rubber remains tight on the pin.

[kmclemore]

Sounds like a decent plan. There have been any number of solutions offered for that noise here on the forum - search back and you'll see. I'll be interested in your results!

[closehaul]

Pitchpole, Regarding the knot, has been awhile but recall it was either a simple overhand or a stopper knot. Your dyneema may require different. I do remember ‘leaving a 18 inch tail on the line’. This gives me something to pull on under the boat should the CB ever fail to lower. Also reduces movement in transport mode. Interested in how much your pivot hole is ‘wallowed out’. I did not repair mine before reinstalling - and regret it every sail (it doesn’t fix itself). Closehaul

[Starscream]

Let me know your 0.02$

When I repaired the centerboard I didn't bother with trying to correct the clunk. We sleep with the board up, of course. I also have the dyneema replacement line, and it's a bit of a problem because it slips too easily through the cam cleats, causing the board to drop at the worst times. I've had to loop the end of the line and hook it over a moveable docking cleat installed on the genoa tracks.

Here's the link to the thread about the work I did on the centerboard:
viewtopic.php?t=27058&hilit=centerboard+bfh&start=30

[mkstocks]

I solved the problem by using a piece of insulated electrical wiring (the usual house wiring - white insulation with two insulated wires inside), about a foot (or less) long. I crawled under the boat, bent the wire in half, fed it up and over the bolt on one side of the centerboard, and gave the wire a few twists to hold it in place. Trim off any excess. The slap never happened again as there was no more free play side to side, and the insulation was slick enough that the up and down motion was not impacted. The workaround took all of 5 minutes.

[pitchpolehobie]

So doing some extra thinking...which is dangerous and expensive for me. I figured maybe insert something like this to help with friction between the rubber and the centerboard . We used these at the base of rotating mast on a hobie 16.

https://www.ebay.com/itm/166330670008

Prob worth a trip to the hardware store to find something similar and maybe less $$$

[dlandersson]

So doing some extra thinking...which is dangerous and expensive for me.

[Russ]

I would probably go with the rubber inserts vs the hard plastic.

[rsvpasap]

Over the years, there have been some creative solutions to this. Just pointing out that Todd at Blue Water Yachts is adamant it's a really bad idea to stabilize the swingkeel pin ("you will break your boat,"etc.)

I copied this mod years ago, which did not involve stabilizing the pin, it's still working fine.
https://macgregorsailors.com/mods/index ... tem&id=390

I also use a Magma rock-n-roll stabilizer hanging from the end of the boom. If I lost the one I have, I would buy another one immediately.

You may find this discussion useful. viewtopic.php?p=335055&hilit=Keel#p335055

[Hamin' X]

Well, You might not want to "fix" it. Very possibly Roger designed it the way it is for a purpose, called a gybing centerboard. Below are some results on this forum for the term and you can do a general search on the web.

search.php?keywords=%22gybing+centerboard%22

[NiceAft]

Rich,

You just emerge from the shadows, deliver your wisdom, and then melt away until the nex time you’re needed.


It’s a bit long, but you get the idea

[pitchpolehobie]

So what do the experts here think about the gybing CB....

[Hamin' X]

Rich,

You just emerge from the shadows, deliver your wisdom, and then melt away until the nex time you’re needed.