Flatback Fireboat Rebuild

[CLM65]

Over the last two Fridays I added a layer of 3/4 oz mat to the bottom to cover the crazing.  As I previously mentioned, I opened and filled the cracks with a vinylester resin/milled fiber/glass bubble mixture.  The mat is an added measure to hopefully prevent any existing cracks from migrating to the surface of the new gel coat, in case I didn't do an adequate job of addressing the cracks with the filler.  I still need to clean up most of the edges where the mat extended past the chines and the keel, but it is close to being ready for fairing.  You can also see the keel extension that goes to about 10" from the transom.

Here is a question for you all...I used VE resin with the layer of mat.  I didn't use any wax in it.  On the starboard side, which I did over a week ago, I just let it cure on it's own, and as you might guess, it is still slightly tacky, and gums up the sandpaper pretty quick.  On the port side, which I did this past Friday, I sprayed a light coat of PVA over it in hopes that it may cure harder and sand easier.  However, it is also slightly tacky after about 2+ days.  What are my options now?  I am trying to sand it with 40 grit to just level and roughen the surface so that I can apply some fairing compound.  Should I apply more PVA to the whole surface?  Could I wash it to remove the PVA, and then roll a coat of VE resin with wax in it to get the surface to harden?  Since it is still slightly tacky, will fairing compound adhere to it the way it is (after removing the PVA, of course)?

[RickK]

I wish I had a great answer (or any answer) for you Craig.  I know that wax closes off the air and the poly (or VE) resin cures. Without wax the resin remains tacky and I think Capt Matt was able to get two or more days (5 rings a bell) before it needed to be sanded for a bond.
I think eventually the resin will off-gas enough and will become tack free.
I think wiping with Acetone might cut it?  That's what I use with poly. Not sure what the cleanup agent is with VE though.
Otherwise, maybe where you bought the product may have the answer?

[Callyb]

Craig, it will eventually cure, but I wouldn't wait if I was you. Personally, and I may be wrong, I would spray with pva to seal it off. The exposure to the air inhibits the cure.I would probably roll the pva on, that way it goes on nice and thick.

Make sure to let us know how it comes out, and what you decide to do of course.

[CLM65]

Thanks Rick and Carl.  I didn't know if there was a "window" after which it is too late to cover with PVA.  I will coat it tomorrow and see how that works.  Hopefully that will do the trick.

[CLM65]

Ok, I applied a generous amount of PVA tonight.  I figure I'll let it sit till Wednesday evening and wash it off.  Should that be enough time?  What is the best way to remove it?  Just water?  Soap and water?  Hot water?  Pressure washer?

[Callyb]

I would most likely use the pressure washer, if it was me. It should take it all off, no problem. I would hope that it is cured by tomorrow, if not I would guess that it isn't going to???

[CLM65]

Yeah, pressure washer sounds good.  I may scrub it with soap and warm water too.  If I don't remove it before Thursday, I won't have a chance for the next two weeks.  I don't know if that may help it cure more, or if it may make it harder to remove.  I can't wait to get the bottom behind me.

[Callyb]

Yeah, pressure washer sounds good....  I can't wait to get the bottom behind me.

Craig, see if you can get it to come of in sheets before you hit it with the pressure washer, which may peel it off in sheets anyway (fingers crossed). Your other comment makes me not want to flip mine over. LOL.

[CLM65]

Carl,

I'm thinking (hoping) that my boat is the exception and not the rule.  The amount of crazing I uncovered when I removed the bottom paint was shocking.  Some had suggested removing all of the gel coat on the bottom.  In retrospect, I'm not sure if maybe that would have been better, but I am where I am now.  Slow progress, but I'm getting there.

[Callyb]

I was wondering how everything turned out? Any updates?

[CLM65]

Hi Carl.  I was going to remove the PVA Wednesday evening, but since I probably won't be able to do any work on it for a couple of weeks, I decided to let it sit for a while.  Maybe that will help ensure the resin cures fully?  Hopefully the PVA doesn't get harder to remove the longer it sits.

[RickK]

I totally understand (not to derail), I was tasked with "other things" like mowing the yard, spraying for weeds, shopping for things I need to cut down the top of my fence and cap it, etc.  Never got a chance to do any work on the boat either. Plus it was smoking hot here - maybe 90?

Back on topic I don't know anything about PVA, so no clue how it'll work the longer you leave it on.  As long as it seals the air out I would think it'll work.

[CLM65]

There always seems to be "other things".  In my case, I had cataract surgery yesterday.  Damn it sucks getting old...and I'm not even 50 yet!  Anyway, they say it takes 2 weeks for eyes to heal, so I'll be taking it easy till then.  Don't want to chance getting anything in my eye and royally screwing it up.  But I am allowed to drink!

[RickK]

Wow, hope you can resist working on the boat 
They say that everyone is growing a cataract - it's just a matter of time.
I hope your eyesight, or critical eye, is not better now after you've done all the work, otherwise you may never finish the bottom.
I hear you about the getting old part 

[CLM65]

I hope your eyesight, or critical eye, is not better now after you've done all the work, otherwise you may never finish the bottom.

LOL.  Before I glassed the bottom, I washed it down.  While it was wet, I looked at it from several angles.  And it didn't look too bad.  I almost said "heck, it's just the bottom.  It's good as-is!"  But the inner me won't let me get away with that.  Not that it needs to be perfect, but I at least need to try to make it better.  Hopefully that won't take too much effort.  And if it doesn't look good, I'm blaming my eyes, even if they are better now than they were before!