Keel repair

Jan 7, 2014
427
Beneteau 45F5 51551 Port Jefferson
My keel got wrapped around my mooring chain last season and I'm getting ready to repair the damage. My plan was to sandblast and grind down to clean metal, epoxy and fair it to match the keel profile. From what I have read, after it's cleaned up, if I epoxy it right away, there's no need to use a rust treatment. I was going to contact west systems for the correct epoxy and filler. I have a 2HP air compressor that can deliver around 7 SCFM at 100PSI. It's a a small area anyway and I was going to pick up a sandblaster at harbor freight. I had some rust spots on the wings of the keel repaired by a "professional" last season and they're already showing through the paint so I want to go the DIY route this year. Is this a solid plan? I hope to do this right and do it once. Any recommendations on a better method? Sandblasting media, epoxy, etc. Thanks in advance.
20191103_155838.jpg20191103_155827.jpg
 
  • Like
Likes: Will Gilmore
Jan 22, 2008
1,659
Hunter 34 Alameda CA
I did something similar. I used a 90 degree grinder with a wire cup brush. It knocked off all the loose rust, exposing the bare metal. I also stripped the bottom paint off the existing keel coating back away from the bare metal that you are going to fill and fair. I treated the keel with Ospho to pickle it. After that it was about 4 layers of glass cloth with West systems epoxy to bridge the exposed iron to the cleaned barrier coat. Then I followed by 3 coats of Interlux 3000 barrier coat. The pictures show a repair up high with the famous "Hunter Smile". Lower down I had to fix the keel by the same technique when my anchor chain wrapped around it .

IMGP1134 Upper Keel Repair Prep.JPG
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2007 06-20 Haul Out - Fwd Lower Keel Damage.JPG
 
Jan 19, 2010
12,543
Hobie 16 & Rhodes 22 Skeeter Charleston
I did this keel...

Keel-oorah.jpg
Keel-trailing edge.jpg


and I started with an air hammer chipper to get to here...

5 hours of hammerandairchipper.jpg


Then a harbor freight sand blaster. Unfortunately I didn't get a pic because I wanted to coat it right away but it did look like shiny metal after...
Here is the coated keel and a pic after I completed fairing and painting

first coat primer.jpg
Ready.jpg



Be very careful with the sandblaster. You DO NOT want to breath any of the dust. Get a 3M respirator mask. Also, if your humidity is high, you will need a drying tube or our line will constantly plug up during the sandblast.
 

Tom J

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Sep 30, 2008
2,309
Catalina 310 Quincy, MA
Your plan is a good one, but I would recommend using a rust treatment before applying the epoxy. I had the steel keel on my old O'Day 23 professionally sand blasted, and coated the keel with a rust treatment recommended by West System. Four coats of epoxy sealed the keel, and a couple layers of epoxy filler faired it. The barrier coat and paint finished the job, and the keel gave me ten years of service with only minor touchups each year, before I sold the boat.
 
Jan 7, 2014
427
Beneteau 45F5 51551 Port Jefferson
I will apply the 2000E last before the bottom paint but I need to fill the missing chunks from the keel. I was going to fill and shape those with epoxy. should I use the glass mat with the epoxy?
 
May 17, 2004
5,413
Beneteau Oceanis 37 Havre de Grace
  • Helpful
Likes: Will Gilmore
Oct 19, 2017
7,797
O'Day 19 Littleton, NH
should I use the glass mat with the epoxy?
Use cloth. Most mat has a binder coating that is not comparable with epoxy. You can chop cloth up with scissors if you need bulk to fill a void.
Mat is good for polyester and vinylester resins because they dissolve the binder.

-Will (Dragonfly)
 
Aug 1, 2011
3,972
Catalina 270 255 Wabamun. Welcome to the marina
Do not confuse "filler", or "fairing", with repair. Replacing a divot or a hole is not done after the first coat of 2000e. It's a protective coating. You don't paint the hull with a nice smooth AwlGrip and then grind out the blisters.

Fix the problems, make it smooth and then finish it with 2000e.
 
Jan 7, 2014
427
Beneteau 45F5 51551 Port Jefferson
I sandblasted and ground down to clean metal and treated it with ospho. Ospho needs to dry overnight and I don't want to leave that bear metal exposed until I can finish it next week. Should I give it a quick covering of epoxy tomorrow to seal it or should i pick up some interlude 2000e as a primer to protect it till next week