Overhauling The Daggerboards (advice needed)

My daggerboards are in pretty bad shape and before I go down the wrong path, I figured I would solicit the board's suggestions and thoughts on what I was thinking of doing. I have already sanded them down and as you can see, the leading edges are pretty much bare of gel at this point and a little nicked up as well.......



More troubling is the fact both boards appear to be delaminating in some places (here is the worst of the delam - most of it isn't nearly this bad)......



I have a quart of West polyester resin and was thinking about wrapping the edges all the way around using 4" fiberglass tape like this......



Is this the right approach? I won't be racing the boat so top-end performance isn't a major concern but I am concerned the glass is going to have a lot of wrinkles where it bends around the curves of the boards. Is there anything I can do to limit this (e.g., cut short strips)? I have never worked with resin and fiberglass before so thank you in advance for your assistance!

First off, it looks like someone painted the boards overtop of the gelcoat. I'd sand all of that paint off to give yourself a consistent surface to work with.

Anywhere the board is splitting at the seam, the first thing I'd do would be to mix up a batch of resin, work some wedges into the split to spread it open and then pour resin INTO the split. Remove the wedges and clamp the halfs of the board together and let it cure.

The idea of wrapping glass tape around the ends might be OK. It would certainly be a good way to keep any splits from opening up..if you can get it to work. I'd go with as thin a glass as I could find for that approach. A heavy weight glass will probably want to pull off the board as it tries to make the turn around the board- particularly on the trailing edge. Also, you'll be left with a hump along the edges of the boards. Another option might be to grind back the edge of the board about 1/16" and do your tape wrap (or two). Then build the edge back up with putty/resin and fair it smooth. The point being that you don't want to go through all this work to lay in new glass only to come back and sand it all away when you fair it in.

To get the glass to follow the curve, you can make cuts in the fabric perpendicular to the centerline of the tape or go so far as to cut out wedges from the fabric.

sm

One easy way to deal with the glass thickness at the edge is to build a quick sanding jig from a 1/2" x 1/2" x 12" long borad and screw a 1 1/2" x 1/2" x 12" board to it to form and "L". Then use spray adhesive and glue sandpaper strip to the 1" section. This will allow you to easily sand exactly 1" in from the edge on both sides where you want to place the galss cloth for strength. You only need to sand approximately 1/8" depth on each side which you would then be able to wrap the cloth and resin it in place. You could then just feather the glass and re-gelcoat.

I used this method when the sides of my Tornado were in great shape, but the top decks were delaminating. I sanded the top sides with this method and when I reglassed the deck it allowed me to wrap the cloth over the deck edge and I did not need to spend much time feather sanding seam in place.

Let me know if this does not make sense and I will take a picture of the sanding jig when I get home.

My point was that getting a 6oz or so glass weave to stay wrapped around the trailing edge of the board while the resin is curing could be tough. You're asking the glass to curve about 180 degrees over an edge that's about 1/8" thick. Unless you can vacuum bag it down or come up with some other way to hold the glass in contact with the edge, it will probably want to lift off of the surface.

sm

Similar to others, I would recommend sanding off all the paint on both sides of the boards first. Sometimes paint is used to hide prior repairs, and any evidence you might uncover of this will definitely give you a better idea of what is going on. Better to know what you are working with ahead of time...

I agree with everybody regarding removing the paint. One time I re- gelled a few sets of dagger boards that were painted and the paint bubbled the instant the gel touched the surface. It took me two days to clean up the mess. You don't want to do that!!

A few things:

You need to re-bond the board back together before you glass it. I dig out the dead foam and fill the void with thickened epoxy, clamp it, and let it cure for a day or so.

I hardly ever need to put glass around the edge of the board like that. If you glass it like that without bonding and filling, you're just putting a bandaid on a festering wound.

Without grinding away a layer of glass and gel you'll make the board thicker and potentially cause a fitment problem.

Here's what I would do.
1) Remove all paint!
2) Bond and fill with thickened epoxy.
3) Fair and assess the strength after epoxy has cured. You may not need it, but if you do glass the edges then grind away some material first.
4) Fair and fill small nicks with Formula 27.
5) Re-gelcoat, fair, buff. (see link)

[youtube]http://www.youtube.com/watch?v=W0fO8TVEtoQ[/youtube]

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Thanks everybody. The paint or whatever it is on the boards is near bullet proof. Believe it or not, I sanded them for about an hour starting off with 150 grit and then switching to 80 grit because I wasn't getting anywhere with the 150. Removing everything might be an all day project. What if I just tried sanding the boards a bit more and then primed and painted them with something tough like Interlux Brightside? I don't have access to a sprayer.

I epoxied the seams shut so I did make some progress. Turns out only one board was delaminating.

I would think an 80 grit sanding disk in a hand drill will cut through just about any paint pretty easily.

sm

I'm not sure what kind of paint was on mine, but using an air powered DA Sander with 60 grit took almost 30 minutes per side. but man did they turn white.

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A couple of things:

The proper repair for this is to cut a slot along the split using a Dremel tool and a cutoff wheel. Then use a thin piece of hard fiberglass sheet to fill the slot with thickened resin. The resin sheet provides a backbone for the filler to reshape the edge. Wrapping the trailing edge with glass cloth as shown will create control problems at speed.

Remember that gel coat does not adhere well to epoxy.

Try not to mix different types of resins - the boats and boards were made with polyester resins. Major repairs should be done with polyester or vinylester resins. Epoxy should only be used for its superior strength and adhesion properties.

You're lucky this isn't SA MB.

OK Matt's right about the resins and not mixing. It's a good rule of thumb. For this repair I do use Epoxy, because most of the time you need the extra grip to glue 2 hammered pieces of foam (core) back together. You can get away with Vinylester, but it's nice just to pump out some epoxy for this one. And you end up with a little bead of glue at the seam. Sand and wash well before gel coating to remove amine blush.

I always spread the two halves open with a couple of screw drivers, dig out some of the rotten foam clean with acetone, fill the void with thickened epoxy, pull the screwdrivers and clamp.

All of those resins will probably work fine for this, for the utter NOOB that was going to go out and buy all the supplies I would probably use vinylester.

I just don't want them to come back split, so I stay away from polyester when bonding. I hate doing things twice.

I do the Hobie 20 rudders the same way. I use a 4" cutoff blade on my grinder and grind out the broken seam, then fill em with epoxy and spray em. They're stronger than when they were new.

Hmmm new video...

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