Has anyone heard of this?

yea, dont do it. its a band aid at best. You can get away with using it in non performance applications but even then i would be hesitant. It just puts off the inevitable.

What about seacast?

refer to post # 2

I will step out here and say I used it with good luck also. But it was also a complete replacement. The original center stringer was a 2x6 in the middle top and a piece of plywood on either side forming an upside down U for the stringer. The center was left open and water just flowed right through it! I dug out all the old wood. I mean every scrap of it from the bulk head to the transom. I then enclosed the ends where the bilge pump and transom drain were and poured the whole center stringer solid. Not going anywhere! The old center stringer actually ended about 3/8" short of the transom, just held there by the glass wrapping it. Now the cast one actually has pegs going into the ply transom and bulkhead. The stringer is also 3" thick, all solid nida bond with the original glass over it.

I also did the bulkhead with it, but I removed all the old wet wood, glassed in a new bulkhead just behind it and then cast the space between them with the nida bond. So my main bulkhead is now the remains of the old 1/2" plywood, Nidabond to fill in where the old wood was removed, and then a new piece of 3/4" plywood. It amounts to a bulkhead about 1.5" think as opposed to the original one that was just 1/2" ply not even completely covered by glass.

Any way you go, you have to remove the old wet wood first and get back to dry wood. I am very very confident in how my repairs turned out. Confident to say it is stronger than when the boat was built. Pretty sure this old resin bucket with end her life someday with that bulk head and stringer still it! I won't ever remove it, that is for sure. The stringer is actually cast directly into the hull also where I drilled short holes in the resin and glass of the keel.

http://www.offshoreonly.com/forums/f...ml#post3640952

Post 36 is where I mention the nida bond. Was easy to work with, but then familiar with composites for the past 25 years or so.

Good luck, just use it right. Use it as a patch and that is what it will turn out to be.

Brian


Good luck

So I didn't really use it to cast into old wood or fill a gap, the new structure is larger or more solid than the old structure.

Ok awesome.... but my dilemma is..... at some point in this boats life someone cut the floor out of it with a skillsaw and ripped right down the center of the stringers. I was going to dig all the old ply out and pour in the nida or seacast because the glass is still holding together perfectly. I just didn't know if I could do that instead of replacing the wood and glassing it.

When I did mine, I cut the top of the stringer off and dug the wood out from there. Once filled, I just floated the old piece of fiberglass on top of the Nida Bond and then smoothed it out and painted. For the bulk heads, I still think it was the best solution. For the stringer, it would have been easier to just replace it. But then I would still have one more piece of wood extending into the bilge. But never having done stringers before, was concerned about getting it back in and locating the motor mounts. I also thought the wood was more rotten than it was. I drilled a test hole and it went through the glass, then I could feel it going into the wood and then it just plunged it! I thought pure rotten middle. Ended up being a hollow middle as built. But once I started, my stubbornness kicked in and I had to finish it. But it is really solid now. Look at the thread, you can see what I did.

If your stringers are just 3/4" ply, I think it would be much easier to just cut them out and replace them. That or cut the top off and use an electric chainsaw to clean it out.d

Brian

Did you replace the wood at all? Or just pour in the nidabond?

For the center stringer that was 3" wide, 18" tall, and whatever length, it was straight NidaBond.

The bulk head was a combination. The area to either side of the center stringer was never glassed in Formula's, so that was rotted. I dug back to good wood and let it dry. I also hollowed out along the stringers going forward from that bulk head. Formulas are filled with foam, so even where the wood was removed, a form was right behind the void. I then fit two pieces of 3/4" glass covered plywood on either side of the center stringer and glass that into place. where the old bulk head was removed, was now a void plus about 1/4" space between the bulkheads. I poured that as one piece with the Nida bond. It flowed between the two bulk heads and into the voids along the stringers going forward.

I did detail all this out in my build thread which I referenced above. Pictures and everything, but let me know if something is not clear. It was a lot of work removing the old wood and fitting everything. I didn't just want to patch it or replace as they did, I wanted to make sure it was stronger as cracked bulk heads are fairly common on the old formulas in the engine compartment. Easier or harder, not sure. I have only done it one way. But it is solid!

Ok cool