How to save your Burchcraft from certain death
I am not sure if all boats are made this way but Burchcrafts have an air gap running the entire length of the boat where the two halves of the boat are clamped together by the inner and outer keel beams.
In my humble opinion this was the primary factor in the nearly total destruction of my boat.
This gap, shown in white below, was created by a quarter inch space between the plywood and a cup carved into the exterior keel beam.
It may have been originally filled with some type of wood putty, but by the time I pulled my boat apart all that was left was a crusty old paper thin rubber gasket.
It doesn't really matter how the water migrates into this gap.
Here's a picture of the symptom on two different boats built 10 years apart
Bob's boat taken a week after he purchased her
My keel. Removed in 1999. Photo taken March 8, 2003. And no, I don't ever throw anything away.......
At this point it is not clear how bad the damage is to Bob's boat, if any.
It is an indication that something needs to be repaired. Correctly that is.
My initial solution to this 14 years ago was to chip off the old paint and apply a new coat of paint.
Then add another coat of paint.
Then add another coat of paint.
This was not the correct solution.
Here's a couple of cartoons showing the migration of destruction.
To prevent this from happening there is a very simple process which I will outline below.
First get your boat out of the water.
If you have one of the smaller Burchcrafts then it is best to turn it over.
Remove the outer keel beam.
This is done by removing the paint from the bottom of the keel beam and finding and removing all of the brass screws which bind the inner and outer keel beams together.
These brass screws are spaced randomly between 6 and 12 inches apart for the entire length of the boat.
You will have to break the seal created by any paint, epoxy, and/or caulking to get the outer keel beam off.
The hull is nailed to the inner keel beam so you shouldn't have to worry about the boat falling apart when you do this.
If it does fall apart, then, well, get a new boat.
Let the hull dry out for as long as possible.
Here's my old inner keel beam with the nail holes spaced about every inch.
The oak used in the construction of these boats is nearly indestructable.
Even with all these cracks, this piece of wood is incredibly strong.
I am fairly sure the nails are what are causing the rust streaks.
I wouldn't recommend replacing the inner keel beam unless your boat is in as bad of shape as mine eventually became.
Removing ~350 rusty little nails would be way too much work.
And after removing the inner and outer keel beams I decided that if they hadn't been as severely distorted as they were, I could have reused both of them.
Wooden boats will after time, take on the shape of their trailers.
My boat had a one inch cup 4 feet long and 4 feet wide.
Cups in your hull are not good.
They do provide excellent stability though as your boat is basically lifting several hundred pounds of water into this cavity.
Hull cups also create huge wakes.
Mini tsunami's to be more precise.
Above is my original keelson laid out on a flat piece of wood.
Below is my original keel laid out on a straight plank.
Don't ask me how my keel took on a lateral wiggle.
Up, down, left, right. It seems to have had a life of it's own.
Back to the subject.
Cover the area as shown, in pink, below with a sealant.
I use Tap Plastics two part marine epoxy.
This will soak into the wood and seal it.
Do not fill the entire gap with this epoxy.
Epoxy doesn't have the flexibility that your boat has and it will crack under the stresses.
Use it as a sealer, not a filler.
I suppose you could use something like Thompson's water sealer.
Next I would turn the boat on it's side and check for damage to the inner core of the hull.
Remove any rotted wood and replace this with epoxy sealer mixed with some kind of filler.
And do it again for the other half.
Next fill in the gap with a flexible sealer.
I have no recommendations here.
...... Phil says use 3M 5200
......High Strength polyurethane formulation (cures with moisture)
Although you don't want it to cure with moisture, so ignore that remark.
......-Flexible -Bonds and seals fiberglass and wood (good for windows as well)
......-Watertight bonding/sealing applications above and below the waterline.
In my opinion you could forego the epoxy sealer step above and just perform this step and your boat would probably last an extra 50 years.
Of course you have figured out by now that the air gap is our primary enemy.
Put your outer keel beam back on before the sealer cures.
Reinstall all of your brass screws.
Add a bead to the inner and outer hull along the keel beams.
That's about it.
Throw the boat back in the water.
If you skipped the sealer and just caulked the gap, this process shouldn't take more than a couple of days, and will save you several years and hundreds of dollars worth of repairs.......
ps. A similar gap also exists between the inner and outer chines.
The contact points are on the edge as both chines are beveled.
I would therefore recommend sealing these also.
Because the gap is only created by the separation of the chines from the hull, I believe caulking all the edges with the chines in place should be adequate.
I used marine epoxy with wood dust filler for flexibility.
This was a mistake.
This mixture is still too stiff and brittle.
see my errors in judgement, #5.
pps. Come to think of it, anywhere that water can collect should be sealed.
Here's a picture of some major repairs to my stbd inboard stringer just aft of the foreward seat.
The wood turning black is a sure indication that the wood has rotted.
Here's a picture of what it looks like from the other side.
The same thing happened on the port side in almost the exact same spot.
I've highlighted the plywood I had to replace.
Since it was meshed between the inner and outer stringers I just inlaid a piece of cedar verneer and covered this with two layers of fiberglass, inside and out.
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