Painting the Boat

[canalflower]

Hi all,

 

We're planning on painting Tamah (mum's boat) this summer, she's been allowed to get pretty tatty by the old owners, so we need to give her a new lease of life!

 

How do we start, clearly we'll rub her down, but do we go back to bare metal? Then what, primer, undercoat, top coat? How many coats? What are good brands of paint? What equipment, will a roller do or should we use a brush?..

 

Are these stupid questions.. can I find the answers elsewhere?

 

Thanks in advance,

Sarah

[WotEver]

Hi all,

 

We're planning on painting Tamah (mum's boat) this summer, she's been allowed to get pretty tatty by the old owners, so we need to give her a new lease of life!

 

How do we start, clearly we'll rub her down, but do we go back to bare metal? Then what, primer, undercoat, top coat? How many coats? What are good brands of paint? What equipment, will a roller do or should we use a brush?..

 

Are these stupid questions.. can I find the answers elsewhere?

 

Thanks in advance,

Sarah

 

Hi Sarah,

 

Lots of good brands of paint - I'll not get involved in that argument

 

I'm no painting expert, but here's a broad brushstroke (sorry):

 

Preparation is king. Rub it down really well with a random orbital sander. No, you (hopefully) won't need to go all the way back to bare metal. Rust-treat where appropriate, and then apply a coat of good primer. Now take a good look and ensure you haven't had any reaction between the primer and any previous paint. If you have, then that'll need rubbing back again (this time to bare metal) wherever it has occurred.

 

Now rub down the primer and apply a second coat.

 

Two coats of undercoat.

 

Two or three coats of top coat. Watch this:

 

Gently rub down between every coat.

 

Hope that helps,

Tony

[Albion]

Hi Sarah,

 

Lots of good brands of paint - I'll not get involved in that argument

 

I'm no painting expert, but here's a broad brushstroke (sorry):

 

Preparation is king. Rub it down really well with a random orbital sander. No, you (hopefully) won't need to go all the way back to bare metal. Rust-treat where appropriate, and then apply a coat of good primer. Now take a good look and ensure you haven't had any reaction between the primer and any previous paint. If you have, then that'll need rubbing back again (this time to bare metal) wherever it has occurred.

 

Now rub down the primer and apply a second coat.

 

Two coats of undercoat.

 

Two or three coats of top coat. Watch this:

 

Gently rub down between every coat.

 

Hope that helps,

Tony

 

That seems good advice to me but always remember that if you have to spot grind/rub down to remove a particularly bad bit of rust that that area will show through when you have the glossy top coats on (gloss shows up all the imperfections that you thought weren't there when doing the primer and undercoat). You may need to concentrate on those rubbed down spots with more coats of undercoat and gentle rubbing down than you will on other sound surfaces. Depends on how good a finish you're looking for of course

Roger

Roger

[WotEver]

That seems good advice to me but always remember that if you have to spot grind/rub down to remove a particularly bad bit of rust that that area will show through when you have the glossy top coats on (gloss shows up all the imperfections that you thought weren't there when doing the primer and undercoat). You may need to concentrate on those rubbed down spots with more coats of undercoat and gentle rubbing down than you will on other sound surfaces. Depends on how good a finish you're looking for of course

Roger

Roger

 

Roger Roger is quite correct

 

When you think the undercoat is good enough, wet it (it makes it shiny) and take a really good look at the finish - if you see hollows or rough areas, then rub down and apply more undercoat etc.

 

If you're starting off with a very uneven surface you can use a high-build primer (basically it's thicker) which enables you to 'smooth out' any problem areas. Also, as Phil Speight recently pointed out to me there's absolutely nothing wrong with using P38 or similar automotive filler for rusty areas (after treating the rust).

 

I prepped a car for respraying many years ago and it took bl**dy ages, but it was worth the effort - it looked like new once professionally sprayed.

 

Cheers,

Tony

[Albion]

Roger Roger is quite correct

 

That'll teach me to go back and add a bit more after I thought I'd finished

 

When you think the undercoat is good enough, wet it (it makes it shiny) and take a really good look at the finish - if you see hollows or rough areas, then rub down and apply more undercoat etc.

 

If you're starting off with a very uneven surface you can use a high-build primer (basically it's thicker) which enables you to 'smooth out' any problem areas. Also, as Phil Speight recently pointed out to me there's absolutely nothing wrong with using P38 or similar automotive filler for rusty areas (after treating the rust).

 

Or you can get a tin of stopping filler, similar principle but finer paste and no hardener needed.

 

I prepped a car for respraying many years ago and it took bl**dy ages, but it was worth the effort - it looked like new once professionally sprayed.

 

It's all in the preparation (as the actress said to the bishop ) but the final finish will very much depend on the time spent on preparation.

Roger

[PhilR]

I've tried many anti rust primers/treatments over the years and none of them have worked - apart from Owatrol Oil which is excellent stuff.

[WotEver]

I've tried many anti rust primers/treatments over the years and none of them have worked ...

 

Use a water based product, use it thinly, prime the area immediately after it's dried, and don't allow the area to get wet until you have the top coat on - both primer and undercoat are porus.

 

T

[Albion]

Use a water based product, use it thinly, prime the area immediately after it's dried, and don't allow the area to get wet until you have the top coat on - both primer and undercoat are porus.

 

T

 

Yeah and they're porous as well.

Roger (singular)

 

I've tried many anti rust primers/treatments over the years and none of them have worked - apart from Owatrol Oil which is excellent stuff.

 

Owatrol is excellent stuff. The only slight downside that I've found with it is that it takes about two to three days to really dry ready for over-coating (depending on the ambient temperature). The surface remains tacky for longer than you'd really like. They claim that you can mix it with the paint that you're putting on top but, if using gloss it can go a bit dull as a result.

Roger

[Chris-B]

Yeah and they're porous as well.

Roger (singular)

 

 

 

Owatrol is excellent stuff. The only slight downside that I've found with it is that it takes about two to three days to really dry ready for over-coating (depending on the ambient temperature). The surface remains tacky for longer than you'd really like. They claim that you can mix it with the paint that you're putting on top but, if using gloss it can go a bit dull as a result.

Roger

 

Errr NO..look at Baldock...the top coats were all retarded with Owatrol oil at about 10%, this really helped with the flow and removal of brush marks

 

And I am not a painter !

 

C

[Albion]

Errr NO..look at Baldock...the top coats were all retarded with Owatrol oil at about 10%, this really helped with the flow and removal of brush marks

 

And I am not a painter !

 

C

 

Please note the use of the word 'can' not 'will'.

 

It depends on the percentage used I believe. Is 10% the recommended percentage on the tin........haven't got a tin to hand at the moment?

Roger

Edited July 3, 2009 by Albion

[WotEver]

Yeah and they're porous as well.

Roger (singular)

 

Oh yeah... thanks to both you and you

[Phil Speight]

Errr NO..look at Baldock...the top coats were all retarded with Owatrol oil at about 10%, this really helped with the flow and removal of brush marks

 

And I am not a painter !

 

C

Owatrol is great as are a number of other brushing additives . The secret with all of them is not to use too much - if you do it`ll look great for a couple of years then it will die the death.So use only as much as you really need - don`t use them to make the job easy - it ain`t.

Phil

[rogerc]

about laying off?

 

i am told it should always be vertically down. but what about the roof channels. is the idea to lay off in the direction rain would run off?

 

cheers

 

roger

[WotEver]

about laying off?

 

i am told it should always be vertically down. but what about the roof channels. is the idea to lay off in the direction rain would run off?

 

cheers

 

roger

 

If your application is good and the air temperature/humidity and flow of your paint is right it shouldn't make any difference which direction you lay off. The argument for laying off vertically is to avoid sags which can occur if the paint is too thickly applied and laid off horizontally.

 

Did you watch this?

 

Cheers,

Tony

[Phil Speight]

If your application is good and the air temperature/humidity and flow of your paint is right it shouldn't make any difference which direction you lay off. The argument for laying off vertically is to avoid sags which can occur if the paint is too thickly applied and laid off horizontally.

 

Did you watch this?

 

Cheers,

Tony

Sorry , I can`t agree with this. If it is true , and my not agreeing is all to do with how I was taught and the reasons I was given - it doesn`t mean I`m actually right by right ( as it were ) - we don`t necessarily have the luxury or the luck to hit the combination of circumstances and conditions you list every time we have to paint. Paint can sag for more reasons than being too thickly applied through simply putting too much on. The optimum amount unevenly spread before laying off can sag just as readily and horizontal laying off only encourages it to do so. Whether it is actually necessary or not laying off vertically discourages sags in paint whatever their cause and , I would have thought , is the safest bet - for non-professional painters at least.

Phil

[WotEver]

Sorry , I can`t agree with this.

 

If you disagree Phil then I will respectfully bow to your superior experience in these matters and admit I'm wrong

[Phil Speight]

If you disagree Phil then I will respectfully bow to your superior experience in these matters and admit I'm wrong

No need to do that at all. I may be equally wrong ! It`s just that , since laying off either way can be argued for, it may prove safest the way that best copes with whatever problems may develop .

Experience is wonderfully useful,but it doesn`t prevent problems . We have two jobs coming back under warranty. This isn`t bad since it makes a total of four in 30 years , and we will correct the problems without argument , but nonetheless it shows that even after all this time neither I nor my staff dare be complacent about any aspect of the job. Paint is bloody tricky stuff!

Cheers

Phil

[rogerc]

Thanks guys, but is it better to lay off along the roof channel or not?

 

Thanks

 

Roger

[WotEver]

Thanks guys, but is it better to lay off along the roof channel or not?

 

Doesn't really matter, Roger. As discussed, the direction of laying off is only in order to minimise the risk of sags which you're not going to get on a horizontal surface.

 

Cheers,

Tony