Hull painting with Roller and Tipping

[GeneM]

Hey, I just finished doing about 40 sqft with Interlux Perfection. It's my first go, so my learing curve is fresh in mind. I don't have help, but did well alone. I focused on just using one foam roller. I got them at Ace Hardware - 4 inch rollers of high density foam. They do go bad after 20 sqft, but just grab another. I thinned to the max 10% for a warm FL day. Roll on thick, but watch for runs. Be sure to go over when the roller dries a little or you'll get bubbles. Leave cut in spots for another day. Roll on and go over as fast as possible. Then leave alone even if there's a bad spot. It needs to be thick or it won't flow smooth. Dust is a problem in the yard, but not critical. Roll rollers on tape to clean them. Everyone says to not paint in direct sunlight. "Direct" is key. Painting in shade means you can't see runs and missed spots. Paint when the sun is at a shallow angle. Finish before 1 PM to avoid condensate flash or cover with plastic sheet. Probably need help for large areas to ensure mixed paint is ready. 20 min induction is critical or you'll get too many bubbles. Good luck.

[Rustic Charm]

Well, firstly, I will be now doing the top coat in two pack I've ordered 8 liters.

The sand blasting is going very slowly on the anti foul. The top sides is coming off easily but the below water is a bit of a struggle.

I am very surprised so far of the condition of the starboard below water. So far no dents, rust or even filler. The problem is that within ten minutes of blasting an area rust develops. I've purchased 10 liters of phosphoric acid and will be giving the side there doing a coat of two pack oxide tonight.

[Rustic Charm]

The task so far

[Rustic Charm]

That orange is rust stains already.

[Snowpetrel]

Can he just give it a quick sweep blast at the end of the day, then blow it down with compressed air while you mix and let the paint induct. Then quickly get a coat of primer on before it gets to late? Much better than trying phosphoric acid.

Also your primer should be tolerant of slight surface flash rust?

Sent from my HTC_0PCV2 using Cruisers Sailing Forum mobile app

[Terra Nova]

Fairing the topsides will be a job of work.

[Pelagic]

Originally Posted by northwestsailor

Found this on YouTube

For this type of unfaired 'commercial finish' this method works fine.
It all depends on what standard of finish you are happy with.

[Pelagic]

Originally Posted by Rustic Charm

Well, firstly, I will be now doing the top coat in two pack I've ordered 8 liters.

The sand blasting is going very slowly on the anti foul. The top sides is coming off easily but the below water is a bit of a struggle.

I am very surprised so far of the condition of the starboard below water. So far no dents, rust or even filler. The problem is that within ten minutes of blasting an area rust develops. I've purchased 10 liters of phosphoric acid and will be giving the side there doing a coat of two pack oxide tonight.

The Hull looks good....take closeups of freshly sanded areas especially at stem and stern for your records.

Normally you don't need any fairing below the waterline in a well built steel hull.....maybe just six inches or so below the waterline tapering to nothing.

Check with Paint manufacturer about using phosphoric acid prior to priming....it may not go well.

[ausnp84]

What sort of blasting is being done (soda, sand, etc)? As we had ours sand blasted during an English summer and never had flash rust come up *that* fast....

On the plus side, if your epoxy primer will handle the flash rust just whack it on straight after.

n

[Rustic Charm]

Well, things did not go as I had hoped. The Bottom is thick. So thick it's taken them all day just to do 'almost' one side. They got to about a meter from the Stern and there boss came and got them.

I had hoped to put a coat of Oxide 2 pack on, but it was way too late. The slip is below a hill and so looses the light at 6:30pm.

The phosphoric Acid was at the suggestion of Norglass. But they said, to put it on and it will take care of the rust immediately then wash it off and clean with Norglass cleaner before I then put a coat of Oxide on. But as soon as I washed off the Acid the rust came back So, as it got late I have put a coating of the acid on and left it till the morning. The sand blasters will be back early in the morning. But frankly I doubt I'm going to get to do anything until Wednesday, 'if' they finish tomorrow.

This picture is of the prop area. on both the front and back leading edge you can see what looks like bog which has been used to round the edges? Anyone any ideas why this would have been done? It's not on the plans.

Also, I have a small hole in the keel, which I think goes into my bilge , and if it is the bilge then it's just 50mm from the diesel tank and the tank is pretty full.

[ausnp84]

I wouldn't be disheartened by it taking a day or so extra... our 43ft'er took 10 weeks to grit blast in and out - I kid you not. 10 soul destroying miserable weeks. Plus it gives you an extra day or so to work out this flash rust issue!

Ok - the "bog" sounds like epoxy filler / filler that's been used to round off some rough edges. Nothing out of the ordinary there.

Tell us more about the small hole... - is the keel hollow or relatively solid? Is there foam in there? How big is the hole, is there much flaking around the area, etc etc

n

[Pelagic]

Totally agree with ausnp84....take your time and get it done right!
I will post you some pictures of my sandblasting in 2010....
Luckily, I was able to convince the blasters to work during the night which allowed me to prime first thing in the morning the sections uncovered.
I was using International Paint products and they etched on very well.

Will post some photos later.

The other thing is to inquire about ultrasound testing of any area that worries you

[Rustic Charm]

The hole is about 4mmsq. I'll check tomorrow but I'm pretty sure it's going into my Centre bilge which is about 200w x 400 long and 400 deep. It was unkept and the sides full of rust when I purchased it. So, it doesn't really surprise me if it has rusted through to the outside. I don't think it will be too hard to fix. If you blow this picture up the hole comes up as a black dot in the middle.

[Rustic Charm]

There's no doubt it's coming up well. But will the topsides be as good this picture shows how far they didn't get too.

[ausnp84]

Ok, just a few things...

- Is the centre bilge still rusty? If so, you'll want to take care of that asap to stop further issues like that hole appearing. We were in a similar position - grit blasting had just finished and I was applying the primer when I noticed a small black area. Hit it with a hammer and found a 0.5mm spot that needed a patch welded over the top. It goes without saying, now's the time to take care of all those little bits.

- Tell the guys to go easy on your topsides!! They blasted ours right back and took out a lot of the fairing filler that had been applied originally.... Really, all they need to do is just rough up the surface of the existing paint - that'll give you a good key to get the new primer on.

- There's a few pics on this page of our blasting - The Rebuild

n