Delaminating tabbing in bilge aft end.

[Oldsailor27]

Hi there,
I am irking in bilge area fixing floor and there is a tabbing delaminating at the far aft end which is extremely hard to reach to sand it off.
It looks that the is some angina oil for there between the hull and tabbing.
Anybody has any adds how to fix it or should I just fill this area with 16 lb density urethane foam and glass the foam over to isolate the are or do I have to open it from the outside, cleaned and glass it?
Please whoever have expertise in the matter please kindly advise.

[Bowdrie]

Wasn't this on another thread, oh, right, that was about the sand.
Anyway, if you ever saw the workers laminating a hull in the mold, (especially from that era,) whether it be a 1-piece or having to connect the 2 halves from a 2-piece mold for an encapsulated/deep/full keel boat you would be amazed it's even possible given the conditions.
If the 2 halves are mostly cured, then the halves are joined, and the mold is tipped first to one side and then the other while workers lay down on in the hull halves and strive to do secondary bonding in an area that has ever less working room the deeper it goes.
For "hot" secondary bonding it's worse, workers lie down on scaffolding lowered inside the mold and do the same job.
Sometimes having to put strips/sections of wetted-out glass on sticks to get it into tight places while wearing protective suits and gloves and with vision obscured with a half-fogged-up face shield.
It's a wonder that more glass is not cleanly and perfectly laid-in and smoothed over, all the while the resin is trying to run and drip everywhere.
A few inches of glass that isn't perfectly bonded? forget about it, or lay down in there to reach down with a Dremel tool.
Are you getting the sand/debris out of the keel cavity?

[Bowdrie]

If you're truly concerned about the integrity of the center-line bonding in that area, then you can drop the rudder, grind off the gelcoat at the back edge of the hull, (wrapping around the sides a fair amount,) and add some exterior laminations of roving with epoxy.
Then fair it out and re-gelcoat.

[Oldsailor27]

Hi Bowdrie,
Yes, it’s the same boat, old Alberg 37 I’m am trying to bring back to life.
I have finished with keel by removing almost whole membrane which was covering the lead ballast, grinder off all the delaminating tabbing and layer new glass over the top lead.
I did remove the wet sand between lead and hull and filled it with epoxy with csbocil. It worked out well.
Now I have moved to bilge are, removed the floor as much as I could and grinder off some of the delaminating tabbing. There is no lead ballast in the bilge are, only sand about 10 ln deep. I have removed all wet and oil contaminate sand and the remaining dry sand is really hard. It brakes if you hit it hard with the screwdriver or it’s getting smoosh if wet, but hard when dry. So I have decided to leave it there as it is really hard to remove it all.
I have already layed some 2 part play sand with west system epoxy mixed with 209. It worked out pretty well. I need to lay same moor of it to level it with remaining bilge floor.
Once I level it with bilge floor my intention is to lay about 1/2 inch epoxy mixed with cabocil to seal it.
After that I am thinking to fill the very aft part with sand/epoxy mixture about 4 inch high to completely cover the delaminating parts of remaining tabbing.
My question is,- as there will still remain void space underneath the sand, would it make things worse? I might add some glass on the outside as you suggested. Please let me know if my plan make sense? This is my first boat and I am fixing it by myself with zero experience thus I ma a bit paranoid.

[AKA-None]

Before you go grinding and removing figure out your plan for how you are going to redo the area
See above for some ideas

[Bowdrie]

I'm certainly not a fan of leaving any "dry sand" anywhere down there and simply covering it up with massive quantities of expensive epoxy.
Before doing a bunch of filling-up of that area aft of the ballast it might be wise to figure out some way of creating a sump into which a bilge pump could be mounted/used.
Yes, I'm sure that getting all that "dryish" sand out is a job, but not as miserable as the original work of doing the laminations in that area.

[Oldsailor27]

Thank you Bowdrie,
I agree, taking sand out would be the best thing to do.
Unfortunately I have already poured one layer of sand/epoxy over the open sand section.
I will definitely make a dedicated sump are for bilge pump.
Is it still ok to leave a small void if I fill r
The aft part?
Would close cell foam work well in that area or it might accumulate moisture?

[Bowdrie]

I see no downside to using a higher density foam back there.
It was/is common practice.
One little trick to pouring foam: If it's possible, try to pour the liquid foam mix down the surfaces of the glass, so that it expands inward upon itself rather than just "dumping it" in the bottom.
I know that's a &(&%@# place to work in, and that old saying about "The best laid plans of mice and men".
It'll be ok, those boats are not "Tupperware", and Carl Alberg knew a thing or three about design scantlings and lay-up schedules.