Replacing teak decks and things

BD = Boatdiesel.com

Awesome thread, thanks for sharing!

Great to see you here sdowney. About the PL roof stuff, I dont like it as much since LockTite bought them out but it still works. I remember the thread on WB where you mixed saw dust with PL premium. I used that a lot, man it really expands. Great for filling gaps and strong. Also used a lot of Sanitred, the learning curve is steep but its great stuff, once you learn how to use it. Folks here could learn a lot by going back to your old WB threads. Good lookin old boat BTW.

kulas44 said:

Great to see you here sdowney. About the PL roof stuff, I dont like it as much since LockTite bought them out but it still works. I remember the thread on WB where you mixed saw dust with PL premium. I used that a lot, man it really expands. Great for filling gaps and strong. Also used a lot of Sanitred, the learning curve is steep but its great stuff, once you learn how to use it. Folks here could learn a lot by going back to your old WB threads. Good lookin old boat BTW.

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Yes, the PL premium polyurethane mixed 50-50 with wood saw dust is a great combo. I filled the plank seams with that and it worked well. Then overcoated with sani tred permaflex. PL is really good, it expands into wood so it seals every crevice so no water can get in there to cause rotting. Cover it with a cereal bag to press it in and it will not stick to the bag. I don't really like sani tred permaflex upside down, it forms runs and drips. IMO, the black PL is a better idea and especially strong if mixed with milled fibers.

You should try mixing black PL with 1/32 milled glass fibers at about 30%. It hardens up the rubber. Straight or mixed, It is easy to smooth onto flat surfaces, just like icing a cake. And it can be sanded with random orbit. I coated the forward 10 feet planks under bow, then I found a rotary wire brush in the drill easily smoothed the black PL mixed with milled fibers. So you can easily contour the coating. No milled glass fibers it does not smooth it very nicely, a rotary brush will actually pull it leaving tiny holes in the surface. But it can be sanded smooth.

It does take a good week to fully cure. If your sanding and it balls up, the sticky balls can be removed with a wet cotton towel rubbed in the surface. Also I found before it cures, it can melted with a hot iron, afterwards it can not. I decided to coat the exterior aft sides where rain water runs down the side and even show the plank edges nicely.

Another issue with sani tred permaflex is before adding new coats, you must wash the surface with dishsoap as it does form an oil during the cure. The Black PL does not do that, it stays very sticky, subsequent coats adhere extremely well. After a week or two the sticky feeling goes away.

Here I have 'encapsulated' the outer surface of the aft planking in Black Pl with no milled fibers. I used a 6 inch flat knife, and troweled - smoothed it over the surface. The white is Dap Dynaflex 230 used to smooth imperfection. Dap sand really well before it cures, sands easily next day wet, after a good cure of a week, sand very fine dry. I do recall wet sanding some of the seams by hand to get is smooth where I stopped and started filling seams. I recall using my finger to fill the seams with the DAP Dynaflex. Since it is so soft it fills very easily the seams. For sanding DAP cuts down fast and is very smooth using 120 grit random orbit paper folded over..



I got it looking really fine. The whole idea was keep out the rain. I dug out all the dried and cracking 45 year old linseed oil white seam compound, Back aft I use Black PL, from aft forward 10 feet. Then after I used the DAP Dynaflex. Dap goes on really soft, but when it cures, it is a hard rubber. I went over the entire boat, took me some time, and it all looks very nice on the hull. Since 2014, not a single seam has cracked open. It still looks like it did in 2014.
Sanded smooth before paint


Seams appearance wet with new paint.



If your trying to achieve smooth defined seems using black PL, use a hot knife edge, like heat a flat steak knife with a propane torch. Drug across the seam it will knock down and make a smooth seam but only for a couple of days can you do that. Then you need to scrub the seam with dish soap and a scrunge what you melted as it turns into a black greasy substance. Otherwise , it is really tough to smooth, if you let it full cure, heat no longer melts it.
The result I thought was worth my effort, and it was an experiment.