Fixing a rusting Keel

[Jboyd]

Hello I am new to sailing and I am looking for some advice on doing
some work.

Last summer I rebuilt a garage in exchange for Pearson P26. The boat
had been in dry storage for 2 years before I put it in the water last
year. After taking it out for the season i noticed that the Keel has
a few rusting blisters that need to be repaired. I have scheduled to
get the bottom sandblasted so that I can start fresh, but I am not
sure where to start.

Do I need to take out the through hulls before getting it sandblasted?
Do I need to prime the Keel prior to applying a barrier coat?
From what I have read the hulls on the P26 have a good amount of flex,
so is one barrier coat better than another?
The keel Hull seem needs to be filled (I guess this is common on these
boats) is there something special I should use?

Thanks for the help.

Jon

[Dan Pfeiffer]

You do not need to remove thru-hulls before blasting.

The P26 keel is cast iron and there are a few ways to deal with it.
Whichever you choose the first steps should be done immediatly after
sandplasting to bare metal because the cast iron will start corroding as
soon as it's exposed. Be sure your sandblaster knows that the keel is cast
iron and will take a different abrasive than the hull.

1) Prime bare metal with a zinc chromate type primer and then apply barrier
coat (e.g. Interprotect) and bottom paint. I did this once and the results
were very good.

2) coat bare metal with epoxy (e.g. West System) using a brass or SS wire
brush to work the epoxy into the surface. This step lifts corrosion off the
keel and suspends it in the epoxy. Before that coat of epoxy has cured do a
second adding a barrier coat additive (I think that's West 422). Repeat
with barrier additive for a total of 4 to 7 coats adding each before
previous has fully cured to get full cross linking between coats. I have
done this too and it is very effective and it makes spot repair simple. I
added pigment to the last 3 or 4 coats to get a more solid color. They have
white and grey. Sand the final epoxy coat for application of botttom paint.
This is a very managable job on the keel of a P26.

For the keel/hull joint I would fill it with West System G/flex epoxy. Dig
out all the old filler you can first. There is a thickened version of
G/flex and you can add fillers. It will cost a bit more to use G/flex but
it remains much more flexible (though not like putty) and is really sticky.


Dan Pfeiffer

[Guy Johnson]

google cast iron keels, there is a fair amount of information on the web about repairing cast iron keels.
Check out Dan's P26 site, I think he has some keel info there.
Most cast iron keels I've seen are pretty rough and need a bit of filler to fair them, depending on the extent of your rust sports you may want to ask the operator to remove all of the bottom paint, but leave the keel fairing in place except for the rusty spots which should be taken down to shinny metal.
Coat the keel with epoxy as soon as possible after having it blasted, use a wire brush to scrub in the first layer of epoxy where you are covering bare metal.
Then you can use waterproof filler to fair the keel, once smooth add another 3-4 layers of barrier coat. Epoxy resin makes a good barrier coat and you can get additives to improve it's resistance to water penetration.
When possible put each coat on before the previous one has fully cured, when you have to let the epoxy fully cure wash with warm water to remove the blush before adding the next coat of epoxy.
 
Guy

> Date: Mon, 30 Apr 2012 10:44:49 -0700
> Subject: [pearson ] Fixing a rusting Keel
> From: co...@fhnwrestling.com
> To: pearso...@googlegroups.com

> --
> You received this message because you are subscribed to the Google Groups "pearson-boats" group.
> To post to this group, send email to pearso...@googlegroups.com.
> To unsubscribe from this group, send email to pearson-boat...@googlegroups.com.
> For more options, visit this group at http://groups.google.com/group/pearson-boats?hl=en.
>

[PQU...@aol.com]

I look at the zinc chromate treatment as a stop-gap measure. It's a quick solution to fix the current rust blooms on your keel. You will have to do different areas of the keel next season, and the following season, and for several more seasons before

 

Coating the iron keel with epoxy and then wire-brushing the keel while the epoxy is still wet is really the way to go. Technically, you can never rid the keel of rust unless you encapsulate it in epoxy. It is incorrect to say that you are "scrubbing" the epoxy "into" the keel. It doesn't work that way. What you are doing is wire brushing (not with a steel brush) the surface of the keel, THROUGH the wet epoxy. This, in theory at least, lifts any iron oxide (rust) and effectively puts it in suspension in the wet epoxy. Even this treatment may take a couple of seasons to fully complete. Go to the WEST web site for more complete information.

 

After you have done the wet epoxy thing you can then use epoxy filler to fair the keel as needed.

 

Peter ~~~~~~_/) ~~~~~~~

[Peter Ogilvie]

Be careful with the sand blasting.  It will take off the gel coat which will make for a lot of fairing to get a smooth hull afterwards.  I'd sand blast the keel but not the hull.  The sand blasting should take the keel down to bright metal which is where you need to begin adding the new paint/epoxy.  POR15 is a paint especially designed for steel.  Haven't used it on a boat but it's been super tough on the frame of one of my LandRovers.  The Paint is very hard and even bouncing off of rocks hasn't scraped it off.  It actually likes a little rust.  I sand blast down to bright metal then let the metal sit for a couple of days to get a light patina of rust, then paint.  Wire brushing epoxy into the keel is used for lead keels.  Lead oxidizes almost immediately after exposure to air and paint doesn't like to stick to the oxidized lead.  Wire brushing the wet epoxy exposes unoxydized lead so the paint sticks.

 

If you want to take the FRP hull down to the gel coat, soda blasting is the way to go if you don't to use chemical strippers or grind it.  It won't strip off the gel coat but will remove all the old bottom paint.  It leaves a relatively smooth surface that you can use an epoxy barrier coat on and then bottom paint.

 

Use a flexible sealant between the keel and hull.  No matter what, the boat will flex at the hull to keel joint.  Epoxy or other hard material will develop cracks.  5200, LifeCaulk, or butyl will move with the hull and maintain a good seal.

 

Aloha
Peter Ogilvie
'Ae'a, Pearson 35 #108

From: Jboyd <co...@fhnwrestling.com>
To: pearson-boats <pearso...@googlegroups.com>
Sent: Monday, April 30, 2012 7:44 AM
Subject: [pearson ] Fixing a rusting Keel

--
You received this message because you are subscribed to the Google Groups "pearson-boats" group.
To post to this group, send email to pearso...@googlegroups.com.

To unsubscribe from this group, send email to pearson-boats+unsub...@googlegroups.com.

[RICHARD USEN]

Excellent idea using POR-15. I blasted the crank pulley on my Chrysler marine engine and painted w/ POR-15 because they weren’t available anymore. That pulley never rusted again for three years, even in the vee grooves. It must be made of seagull crap or barnacle cement!

To unsubscribe from this group, send email to pearson-boat...@googlegroups.com.

[Jboyd]

Thanks for all of the advice. After looking into a couple of these
option I thing the POR-15 might be my best option I talked with a
representative from the company and according to him it is commonly
used on boats. Either way the worst that can happen is I am right
back n the same spot next spring!

I am a little more afraid now of having the whole bottom sandblasted.
It currently has an ablative paint on it, but like I said it sat out
of the water for at least 2 years and I have no idea whats under it.
Am I better off just getting the keel sand blasted and use a paint
remover and sander to take the rest of the bottom paint off? Th guy
doing the sandblasting works on boats all the time.

Also should I barrier coat the whole bottom once I have the keel
sealed and the bottom paint removed?

Thanks again for the help.

> pearson-boat...@googlegroups.com.
> For more options, visit this group athttp://groups.google.com/group/pearson-boats?hl=en.

[R Bibs]

For what it's worth I just finished a total bottom job on my P 31-2. I used Peel Away rather than soda or sand blasting to remove the 20 plus years of bottom paint down to the existing barrier coat. I then applied three coats of Pettit Protect and two coats of paint. The project turned out great but it was very time consuming and very labor intensive as there is still quite a bit of prep work such as sanding and surface cleanup whether you blast or use a chemical stripper. 

Good luck with whatever you decide.  

[RICHARD USEN]

I'm not sure what the hull looks like. I just bought a boat that had sat
for quite a while and had ablative paint on it. It was smooth and not
flaking, so I just rolled on another coat. My last boat had some flakes
coming off every year in different places. I scraped these areas until I got
back to solid paint and then feathered the areas, spot painted and then
rolled on a full coat. If it had been flaking and loose everywhere, I
would've stripped it, one way or another and barrier coated it. I've
stripped boats w/ a hook scraper and would never do it again. Then again,
I'm not competing in the America's cup.