Fiberglassing the daggerboard

imported_Brad

New Member
My daggerboard is almost completely bare wood (the varnish is gone). I've heard that these can be fiberglassed using just the resin and not any fiberglass mat. I've also heard that it's best to brush from front to back on the daggerboard instead of top to bottom so that the water flows better. Does anyone have any tips on doing this? Is 'Bondo' brand resin from Wal-mart O.K.? How many coats should I do? Should I sand the wood smooth?
Thanks for the help!
Brad
 
I just finished varnishing both my rudder and daggerboard. I used Interlux Goldspar Satin 60. 1 pint was more than enough for four coats. I would recommend sanding with 220, then steelwool in between coats. Since the foils will not be in the water that long, the interior varnish is fine. I think :confused: that Bondo is polyester resin which is not compatible with wood. Epoxy resin seems like overkill to me although it could be done. Polyurethane varnish is not as obnoxious to work with as epoxy resin. Polyurethane is much easier to sand than epoxy. My 2 cents.
 
Ok, ok. Now would you believe the way I brush paint on my house affects it's ability to shed rain water? If so, I've got a bridge I'd like to sell you!

This is the third time I've mentioned using a 2 part urethane that's supplied by an aircraft supply house. I guess most must think I'm joking when I say this stuff will last 20-25 yrs. Mahogany and Phillipine Mahogany are beautiful woods. It's well beyond me why anyone would paint them with polyester resin (fiberglas) !!!
 
Polyester resin is hydroscopic meaning it attracts moisture and has to be sealed with something else. So it's not a good thing for something thats going to spend a lot of time under water.
West Systems epoxy resin dries clear and provide a tough shell shell for the daggerboard.
Fill any dents and sand the wood smooth. You don't need to go to 400 grit but a really rough surface will come through in the final finish.
And yes if your brushing not spraying front to back will leave little brush lines that will follow the water path, rather than brushing up and down. which will leave the same brush marks against the water path.
 
One post script: If you use WEST epoxy or other similar epoxy resins (with or without fiberglass mat) it will turn cloudy and dark after prolonged exposure to the sun as these resins do not typically have a UV filter built in like some other coatings do. Some people coat bare wood with an epoxy resin and then put a few coats of a varnish with a UV filter over the epoxy but you have to make sure that you use a varnish that is compatable with the expxy resin. I recall that this process is covered in the manual available from WEST marine products. In any event, all this seems like overkill. Just sand and varnish the board with a good marine varnish (Interlux Scooner is my first choice) or a marine poly. varnsh. Good luck.

Alan Glos
Cazenovia, NY
 
Thanks for all the great advice! I'm going to simply varnish the daggerboard. How many coats do you reccomend and how much dry time do I need to allow between coats (I actually have a day to go sailing coming soon and I want to go!).
Thanks,
Brad
Payson, Arizona
 
Arizona huh?. If it is dry and warm where you are, 12 hrs between coats would be sufficient. 4 coats minimum if you plan on keeping up with the varnishing. A coat in the morning and a coat at night could have you finished in a couple of days depending on what brand you buy. Read the label. I agree that the wood is too beautiful to cover with goop. :)
 
In a place like Arizona, be sure to varnish in the shade or the varnish will dry too fast and may not flow out properly or even form bubbles on the surface. Follow the directions on the can carefully. The key to good varnishing is sanding/steel wooling between coats so you are always putting the new coat over a dull, smooth surface.

Alan Glos
 
OK, I was in a hurry to go sailing and I put only two coats of varnish on the otherwise almost bare wood. After about 4 hours of sailing when I went to remove the daggerboard it was VERY difficult to get out. I had to place the end of the daggerboard on the concrete launch ramp and push down on the boat to get it out. When I finally did I saw that it was warped. Is this because I didn't put enough coats of varnish on? I am hopefull that it will straighten out. I have it hanging by a hook right now. Am I going to have to get a new board?
Brad
 
Actually I paid more attention to the ends. I did have it hanging while I was varnishing it, do you think enough could have dripped off so that it wasn't sealed properly? Although, I didn't see drip marks on my concrete.
 

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