Wednesday, September 28, 2011

Keel and Bottom Work Procedures

Keel and Bottom Work Procedures


The Complete Procedures:

  • Keel Preparation: Stripping the Keel
    • There is no easy way to do this, unless you have access to and permission from the boatyard to use a sandblaster. This would probably require you to tent off the boat.
    • Cover the ground and use vacuum hoods on power tools for environmental reasons.
    • Chip and scrape as much as possible with an old chisel and stiff scraper, being careful when you are working near the joint and fiberglass stub.
    • Using an angle grinder (with dust hood) and sanding disks, sand off as much as possible. This step will take the longest and remove the vast majority of the remaining material.
    • Using and angle grinder with a course wire wheel clean up what remains and try to get to bare metal wherever possible. Make sure you remove all rust.
    • Immediately before applying the epoxy barrier coat, do a quick but thorough sanding with an orbital sander and course paper (30-40 grit) to take off the inevitable (and unseen) oxidation that begins immediately when iron is exposed to oxygen.
    • Dispose of collected material properly -- whatever that means. In my case, I collect it in a 5 gallon bucket and dispose of it when our local county landfill collects hazardous waste.
  • Keel: Applying the Barrier Coat
    • The steps below must be done quickly as oxidation is occuring while you wait.
    • Having removed the flash oxidation with the sander, clean surface of dust with tack rags.
    • Wipe the entire surface with acetone to remove oils and water.
    • While the acetone is drying, begin to mix your unthickened epoxy. Mix thoroughly!
    • Apply epoxy to a small area (2 sq feet or so) with a foam brush or roller, being sure to get into all the pits and crevices.
    • Scrub the area with a wire brush to increase the epoxy's contact with the metal. 
    • Tip off the wire brush marks with vertical, then horizontal brush strokes.
    • Repeat the last three steps until the entire keel is coated.
    • Subsequent coats may be applied right away, as long as the epoxy hasn't cured completely. Otherwise before applying the next coat you will need to scrub off the amine blush with a green scotch pad and dry if off, being sure to collect all the waxy blush residue.
    • As you go through this process and the epoxy begins to cure be sure to keep an eye out for drips and sags. Unthickened epoxy, especially on a hot day, is VERY runny.
    • After two or three coats, begin to fair the pits and crevices with epoxy thickened with your favorite fairing compound. (I use west systems 407 as it sands easily but still has some structural strength to it). Let fairing coat dry.
    • Sand your fairing coat smooth and clean the surface with tack cloths and acetone as before. Recoat with unthickened epoxy. Note: if there are really deep pits you may have to do this a couple of times to fill the holes.
    • You will need a total of 5-6 coats of epoxy to thoroughly protect the iron from oxidation and galvonically isolate the iron from the copper in the bottom paint. Remember to wash the amine blush off the surface before painting.
  • Sealing the Keel to Hull Joint
    • Scrape out as much of the old sealant as you can reach with your favorite pointy tool.
    • Clean the area in and around the joint thoroughly -- no dirt, no oil, no rust.
    • Douse the joint in acetone to remove moisture that may linger deep within.
    • Tape off both sides of the joint to ensure a neat edge. (This allows you to be really sloppy with applying and smoothing the new sealant.)
    • Using 3M 5200 and a caulking gun, apply a thick bead of sealant along the joint. Be sure to squeeze as much sealant into the joint as you can.
    • Smooth off the sealant while it is still wet and sticky (wear latex gloves!)
    • Remove masking tape and allow sealant to dry (up to 7 days)
  • Fairing the keel to hull joint.
    • Take this advice/procedure with a grain of salt. As iron is obviously not flexible and fiberglass is, I suspect there is some flexing in the joint. Fairing over the joint with thickened epoxy thus has two problems; if the hull flexes at the joint the epoxy will crack, and I am not sure how well epoxy will adhere to the 3M 5200.
    • If you fair the areas above and below the joint only, you would be able to monitor to state of the joint at every haul out. If you cover it, who knows. The down side is it will not look or perform as well as covering the entire joint.
    • My (unproven) solution to this dilemma was to use West Systems GFlex epoxy, thickened with fairing compound to cover the joint and blend the keel seamlessly into the hull.
    • The procedure is identical to the fairing process above.
DON"T FORGET THE BOTTOM OF THE KEEL! 
(Although there is not much you can do about the area where the keel is resting on the blocks -- unless you want to pay the yard to hoist the boat on the lift while you work on those areas. That can get really pricey as the yard will charge by the hour for the use of the lift.)

I won't go into detail about how to paint the bottom as this is covered extensively elsewhere online.

Sunday, September 11, 2011

Keel, Rudder and Bottom Work

Before any work
The culprrt: poor maintenance of the forward
part of the joint allowed water to penetrate along the length of the joint.





(All images @ https://picasaweb.google.com/113905172205315068165/ElizabethKeelAndBottomWork)

The big job at hand is to strip the keel back to bare metal, apply an epoxy barrier coat, reseal the keel/hull joint and fair and paint the whole mess (including the entire bottom). The rust visible on photos above is nothing to worry about, just surface rust. It does, however, indicate that the old barrier coat has failed. I received a quote from Oak Harbor Marina to strip, barrier coat and paint the keel --  a mere $2400. So I will, obviously do the work myself. Alas.

Armed with hammer, chisel, scraper, random orbital sander, angle grinder, shop vac, dremel, safety glasses, hearing protection, and respirator I set to the job of stripping the keel of all the old material. This is a seriously SLOW and laborious task. It would go a lot faster with a sandblaster, but the yard won't allow it.

The First Weekend
After most of a day's work I managed to expose the keel/hull joint and chip away at some of the old barrier coat. The joint was faired with a material that looked a lot like Bondo. It adhered tenaciously to both sides of the joint, but not over the area of the joint itself. Ranging from 1/4 to 3/8 of an inch thick it took  a couple of hours of careful chiseling to expose the joint.

The surveyor was right, the polyurethane sealant in the joint remained intact, except at the forward end. My worries about moisture getting to the keel bolts was unfounded. I used the hook scraper to dig out as much of the old sealant as I could reach, leaving just some detail sanding necessary before applying a new bead of 3M 5200. I will prep the joint on both sides of the keel before sealing the joint.

After a couple of days of VERY slow going with lousy sandpaper and  lots of hammering and scraping, I decided to purchase a dust hood for my angle grinder. With the grinder I can use a wire brush. I am hoping this will go faster.

The Rudder: Day 1





I also began the repairs on the rudder. The starboard side of the rudder had a couple of wet spots with one serious area of delamination. I did a quick sand job just to expose the high points, then drilled a bunch of holes in the bottom of the rudder and a couple on the top to allow the water to drain. Water flowed as if the faucet was left on! I let it run for a day and on day 2 started to cut out the areas of delamination. I was surprised to find no fiberglass cloth or matting -- just thickened epoxy. Below the skin is a very dense foam material. I hope when I relaminate the cut out areas the epoxy will adhere to this stuff!






After 4 days ... damn this is slow going. Found the fastest method was to remove as much as possible with a hammer, chisel and stiff scraper. This will get off most of the old barrier coat without creating too much dust. Then the angle grinder with a sander attachment will do the most of the rest. Finally finish off with a wire brush. The orbital sander is worthless.

September 17 2011
After a week finally a coat of epoxy is on the port side of the keel and progress is being made on the starboard side.






September 24 2011
Two weeks later and both sides have at least one coat of epoxy and the keel/hull joint is sealed with 3M 5200.

Before any work on the starboard side

Starboard side -- joint sealed and fairing begun

Taped the joint for a neat joint line
October 5 2011

Almost a month later and the keel, hull and rudder are as done as they are going to get. At some point you have to give up on perfection and recognize you are out of time. And boy did I give up on perfection! The keel has been stripped, the joint refreshed and the area has been (somewhat) faired. More time and I would have made a perfect fairing job of it. Alas.





After one coat of bottom paint ...






















And The final product ... after two coats of bottom paint.



Sunday, September 4, 2011

Sailing Her Home: Baltimore to Solomans Island


























Sixty-nine nautical miles, a full tank of diesel and light southerly winds forecast -- not a great scenario for a sail. Still, my brother in law was available to help me sail her home and we had to go for it -- even if it meant motoring the whole way. Thankfully my sister was up for driving us to Baltimore, an hour and a half away from home in Southern Maryland.





We got off to an early start, departing Oak Harbor Marina around 7:30 am. The winds were non-existent and we had an easy motor out into the Bay. As we headed toward the Bay Bridge the southerly winds began to pick up. Unfortunately, the wind speed indicator was not working so we were not really sure just how much. By the time we got to the bridge we were motor sailing and making about 6 knots.




By this time we should have put a reef in the main, though it was not obvious yet. Steve and I took turns at the helm, with Steve carrying the larger burden while I played deck monkey. This being her first sail for a couple of years the tackle was stiff and everything was new to us. Fortunately a sailboat is a sailboat and there are only minor details to be sorted. For example, I didn't at first realize she had two-speed winches! Alas.



The waves were getting bigger but Elizabeth sailed very well. Her sails have all been refurbished and held excellent shape. Turns out her original owner must have taken her sailing performance rather seriously, despite the family cruiser design of the boat.




11 hours later and we were entering the Patuxent River. Things were a bit hairy now. We were definitely overpowered and thundering through 6 foot waves. We were over heeled which slowed us down and the weather helm was massive. Fortunately, Steve was at the helm and held her firm. As we motored up Cuckold Creek, Elizabeth's new home, Steve commented that it was a "spirited" sail. A bit much for me! I'd have opted for more control, less heel and greater comfort, but I guess that is why I am into cruising and not racing.

Looking straight down. Thank God for the cooler!




The trip took 12 and a half hours, beating into the wind and averaging more than 6 knots the whole way - with a couple of moments where she passed 8 knots! (Ok, that was surfing down a 6 foot wave where we immediately lost 4 knots when we became sandwiched in the trough!)

I did not get my land legs back until the next morning. A spirited sail indeed.