Mac 26x Swing Keel

[CasualSin]

Discovered this on a Mac i bought last year


Someone obviously tried to fix it



...foam really???
Anyhow i am thinking to give it a shot, just wondering if i can find any advise here on whats the best approach on this one, thx.

[Starscream]

My suggestion:
http://shop.bwyachts.com/product-p/5402-1x0.htm

I tried my first fiberglass project this year, glassing insulation into bottom of the cooler box. All I can say after that experience is that the centerboard isn't the place to start learning to lay up fiberglass.

[CasualSin]

Thx, disagree.

[DownSouth]

I did a 'not as bad as that one' similar repair of an X board. It was a bit of glassing but the centreboard could benefit from a bit of extra weight so I used the marine fibreglass impregnated two part epoxy putty. May be used for car repairs where you live - but not what I think Canada / US calls 'Bondo' which is a car putty that I think is hydroscopic and not suitable for underwater repair.

The foam was probably an attempt to get some sort of form to lay the glass over?

DownSouth

[CasualSin]

...thx, was thinking that way, not sure about all the marine epoxy systems, more like bando 764 long strand, its waterproof and cheap $35 for a gallon. Gotta sick to a budget, i would buy something like Benetau othervise, not a Mac

[Snowdancer]

Good luck.My first attempt at fiberglassing was to add 2 missing feet to bottom of swing keel did not go well. Eventually bought a new one. Suggest using a wood mold inserting into lower sectione. Then cover all with fiberglass including oversized holes. There is a knob on bow side of keel to keep it from going pass center. Will see if i have a picture.
At same time fixed buddies keel axle hole that had pounded out too using a stainless sleeve. He said it made a noticeable performance enhancement.

[CasualSin]

....wood mold??? that would add flotation to the keel, i think im just gonna create the missing bottom 12" out of that long strand bando, that will add couple lb and will make the keel drop faster, and put couple layers of glass on it to add integrity. If it fails its a $50 loss vs $689 out of pocket for a new keel ....unless there is a better suggestion of course...thx.

[opie]

1. see this link
https://sites.google.com/site/centerboardholes/
2. My board has an ear on it to stop it. Does yours?
3. My 1999 board had brown absorbent foam it it from the factory, sorta like sea sponge.
4. Board must be full of water to work. My board has two holes in bottom and one in top. It fills and therefore drops in about 10 to 15 seconds.
5. Board should have no weights in it.
6. Can't have bouyant foam or wood in it or it won't sink properly.
7. Fulcrum pin must be sloppy by design since the board canterwomps against the chamber and locks tight as a drum at speed and at any position of lowering. Those that add steel tight axle therefore don't understand the original ingenious design. You should hear a racket at anchor with board down if properly hinged.
8. I had to re-make the bottom 8 inches of my board after dragging it, deployed, 20 miles while trailering. I used good old Bondo and then painted it. That was 10 years ago. Lots of use.
9. Fiberglas is easy. One project completed was to fill in a hole that PO made in hull with his trailer tire at highway speeds when trailer busted. I put in 8 layers. And gelcoated with a brush. Good looking from 3 feet away.

[opie]

Wow, what an exaggeration!! My conscience bothered me last night. This morning I searched my old computer and found my 2006 repair file. It wasn't 8 inches of Bondo. It was more like 2 inches. Here is my file story.https://drive.google.com/file/d/1nCAJZn ... p=drivesdk

One more comment or two.
The board pic you gave, could that board be non-26x? It seems strange somehow. And the business end is affected, not the bitter end. You will need an exact model I think to get it to work and fit. Can you borrow someone's center board for that?

[CasualSin]

...no, the board is hollow. There is rigid box in a middle of the board through all lenght, that box only is filled with sponge. It could have been removed by previous owner during repairs. the stopper knob u mentioned also was there ......broken. I guess i will create one also. I have no access to a sample board, so i will just have to go with what i have. Thanks for the info any way.

[Starscream]

Here are photos of the top of the centerboard, if it helps:

[CasualSin]

....yup, mine is broken. This one is rather easy fix, i will look into it later on. Older mac keels did not have that stop any way as far as i know, thx for heads up man.

[CasualSin]

....ready to glass?

[Na2K]

Hi,

I am looking to repair my centre board the same way you did. Wondering how the long stand fibreglass filler has held up for you. Would you still recommend using it?

Thanks

[OverEasy]

Hi All!

Kinda weird original posting with a chunk of foam in the middle of it and rotten wood piece.
As designed the swing keel is supposed to be hollow and is supposed to readily flood when dropped.
Added weight isn’t gonna help much at all … actual weighted keel boat at 26 ft length of similar displacements would need to be several hundred pounds… the Mac26 sails just fine with just the flooding swing keel. The wing “airfoil shape” does the work more effectively than just weight would.

If one wants to make/repair a swing keel fiberglass over a styrofoam form is fine but one would need to make fiberglass ribs and stringers on the interior area and after the fiberglass & resin is cured use acetone to dissolve the styrofoam out. Messy and very flammable but effective. One will need about four biaxial layers for the sides and a reinforcement layer set on the leading edge. The top pivot portion needs to nearly solid. It’s an involved process which is why the BWY replacement costs what it does. A swing keel isn’t a great place to start learning to do DIY structural work to be honest… there are a lot of forces at play…

Just my two cents…

Best Regards,
Over Easy