Immediate delamination

[Jack2048]

Hey all,
I am working on rebuilding my 1994 caravell interceptor, 23 ft bowrider.

Yesterday I added some 1708 tabbing to my new transom (interior mounted ). I went to check it today and i was able to pry the tabbing off the hull with a flat blade. The transom bond is good. I guess I didn't surface prep the hull properly but not sure what I did wrong. I am going to switch to epoxy as my neighbors are sensitive to the poly, but need to understand the problem before proceeding.

My poly is fresh, bought a few weeks ago.
I angle grinded the hull with 40 grit.
Cleaned with acetone.

Not sure of the issue.

Guidance ?

 

[kcassells]

pics

 

[Jack2048]

pics

 

[kcassells]

Ouch!! Looks like the glass wasn't wet out enough is all on the transom. The glass on the keyhole shouldn't be that dry/fluffy.
The hull glass appears to be the same. It maybe bad mixes. Needs removed, sanded, acetone and reglassed.

 

[Jack2048]

Ouch!! Looks like the glass wasn't wet out enough is all on the transom. The glass on the keyhole shouldn't be that dry/fluffy.
The hull glass appears to be the same. It maybe bad mixes. Needs removed, sanded, acetone and reglassed.

What you are seeing is that I already pulled off the glass.
It was attached to the hull, but separated too easily when I pried it. I put poly on the hull first, then laid glass on top of the wet poly, then used a roller to apply poly on the glass.

 

[Scott Danforth]

going to guess that the surface wasnt clean or the resin you got was bad.

but that all has to come off

 

[Jack2048]

>going to guess that the surface wasnt clean

That's what I was thinking, but not sure where I messed up as a sanded and cleaned.

or the resin you got was bad.

The glassing worked fined on the new transom. Put on three layers of 1708 with the same poly, worked great, nice and hard.

but that all has to come off

That's what you see in the pic, is that I have started re-grinding to remove what didn't stick.

 

[Lectro88]

If the surface is contaminated with "something" (And It would have to be really bad)
When you grind it or sand it, you "Can" just smear and spread it around, also get it in your grinding pad. And just keep spreading in different places.
Now that is Very extreme, I have not encountered what you show...
Typically when I sand or grind, it's ready for Goop/Resin.
You have something going on.
If you hadn't had good adhering already in a different place, I'd suspect a bad/stale resin or bad un-properly mixed product.
Was there maybe due/moisture when you applied ?
Or did you spray at some point anything.... like a bug spray or Off. (I'm grasping)

Maybe try (again)a test spot not on or in the boat, is a different option.

 

[Jack2048]

If the surface is contaminated with "something"
When you grind it or sand it, you "Can" just smear and spread it around,

There was gelcoat that I ground off, originally.
Right before I went to lay the glass, I sanded with new 60 grit paper, vacuumed, then wiped w/acetone. So, I am not thinking it is something I "smeared around".

Now that is Very extreme, I have not encountered what you show...
Typically when I sand or grind, it's ready for Goop/Resin.

That's where I thought I was at.

If you hadn't had good adhering already in a different place, I'd suspect a bad/stale resin or bad un-properly mixed product.

Where the resin is soaked into the glass, it is rock hard. The product is fresh and worked fine on the transom itself.

Was there maybe due/moisture when you applied ?

No.

Or did you spray at some point anything.... like a bug spray or Off. (I'm grasping)

Keep grasping! But, no.

 

[Scott Danforth]

There was gelcoat that I ground off, originally.
Right before I went to lay the glass, I sanded with new 60 grit paper,

40 grit minimum. I use 24 grit

 

[Jack2048]

40 grit minimum. I use 24 grit

I had already used 40 grit to remove the gelcoat, but it had been a while since I was able to work on it, and went over it real quick w/60.

 

[Lectro88]

From everything you say, you did everything right, And I would have expected better results too, (maybe not enough wetting like others said)I am t at a loss at this point, Sorry.

I can say with pretty good confidence, IF you change to epoxy, as you say you Plan.
You should see better results, Epoxy typically Bites a litttle Better.

Don't feel targeted, You do enough of this,,. And it happens Sometimes to us All.
Sometimes it just doesn't Take,. Weather, humidity, product, user error, or some of all, pick a card.

 

[Jack2048]

From everything you say, you did everything right, And I would have expected better results too, (maybe not enough wetting like others said)

That's what I thought, thanks for confirmation.

I am t at a loss at this point, Sorry.

Hey no worries, so was I, which is why I posted here.

I can say with pretty good confidence, IF you change to epoxy, as you say you Plan.
You should see better results, Epoxy typically Bites a litttle Better.

Right, so I used epoxy in other places and with the stringers , not pictured, and transom, and have had great results.

I am almost out of poly, 1/2 gallon left, and the fumes have been bothering my neighbors, they are super sensitive to that sort of thing. I went over there w/a care package to make nice. They are super great people. So that and epoxy being so pleasant to use, is just another reason to use epoxy on the rest of the rebuild.

Don't feel targeted, You do enough of this,,. And it happens Sometimes to us All.

???
Thanks, I don't feel that way. I appreciate people here trying to help me.

Sometimes it just doesn't Take,. Weather, humidity, product, user error, or some of all, pick a card.

Good to know.

 

[froggy1150]

Is it possible there was a previous repair done in that spot with epoxy already? I had to do my bilge in epoxy due to a repair i couldnt grind out because i wouldnt have had a hull left in that spot. After doing the bilge i did transition pieces to isolate the epoxy and went back to poly

 

[Jack2048]

Is it possible there was a previous repair done in that spot with epoxy already? I had to do my bilge in epoxy due to a repair i couldnt grind out because i wouldnt have had a hull left in that spot. After doing the bilge i did transition pieces to isolate the epoxy and went back to poly

Interesting. No. The area in question is also the bilge. I ground out the gelcoat, all was original / factory work.
I made some peanut butter to gap fill between the hull and the new transom. That has set up properly.

 

[KJM]

Thats strange...is it possible the cloth itself got contaminated? maybe layed somewhere where oil or something got on it?

 

[Jack2048]

Thats strange...is it possible the cloth itself got contaminated? maybe layed somewhere where oil or something got on it?

Nope, no way, clean as can be. Bought a roll of it, cut it off, layered it on!

 

[froggy1150]

Must be cat ****......
That stuff ruins everything

 

[froggy1150]

Pee

 

[88 Capri (2022 SOTY)]

Nope, no way, clean as can be. Bought a roll of it, cut it off, layered it on!

I had a similar issue when I started my project in which I started being alot more generous with the acetone and putting a coat of resin down prior to laying and wetting the cloth and it really eliminated that issue for me.