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SS[_2_] July 12th 11 09:38 PM

How many coats of undercoat
 
Is there a limit to the amount of undercoats to put down before applying a
final coat of gloss.
One side of my porch gets hammered by the weather over winter and have
currently I have taken it back to the wood, so far I have given it 2
undercoats but wondering if there is any benefit by giving another couple of
coats before a final gloss.



The Natural Philosopher[_2_] July 12th 11 10:24 PM

How many coats of undercoat
 
SS wrote:
Is there a limit to the amount of undercoats to put down before applying a
final coat of gloss.
One side of my porch gets hammered by the weather over winter and have
currently I have taken it back to the wood, so far I have given it 2
undercoats but wondering if there is any benefit by giving another couple of
coats before a final gloss.


primer is more to the point I'd have thought.

Wood painting I reckon goes like this

1/. Knotting to seal any resins.

2/. Primer to key to the wood and fill the grain. Lots of coats

3/. Undercoat to build up colour

4/. Gloss to be a protective layer and bend the undercoat colour towards
final.

So I'd say put on more TOP coats.
the key thing is an impernmeable top coat. Id probably recommend a two
pack yacht pain if I knew more about those. But they are reputed to be
the dogs ********.

Charles[_8_] July 12th 11 11:13 PM

How many coats of undercoat
 
On 12/07/2011 21:38, SS wrote:
Is there a limit to the amount of undercoats to put down before applying a
final coat of gloss.
One side of my porch gets hammered by the weather over winter and have
currently I have taken it back to the wood, so far I have given it 2
undercoats but wondering if there is any benefit by giving another couple of
coats before a final gloss.



As previous message said. One maybe two undercoat either combined with
primer, or primer first (too late now), two top coat gloss. Don't
overdo it in coats. very light sanding in between coats (I use 180 or
240 grade) some prefer wet and dry.

Use a recognised brand of exterior paint, and follow their instructions.

Cheers
Charles

Cash July 12th 11 11:16 PM

How many coats of undercoat
 
SS wrote:
Is there a limit to the amount of undercoats to put down before
applying a final coat of gloss.
One side of my porch gets hammered by the weather over winter and have
currently I have taken it back to the wood, so far I have given it 2
undercoats but wondering if there is any benefit by giving another
couple of coats before a final gloss.


SS,

Try two coats of undercoat and two coats of gloss (that usually gives me a
five year life on outside work) - but it is far more important to prepare
the surfaces properly first.

I.E.


1 - Rub down to remove all loose and denuded areas - ensuring that all paint
edges are 'feathered' and all sharp edges of wood have arrises removed
(slightly rounded)

2 - Repair any damaged areas properly (renewal, filler etc)

3 - Full prime or spot prime any bare or new timbers - and rub down when dry

4 - Check priming work for missed or damaged work - and touch up as
necessary - light down when dry

5 - Apply first and second coats of undercoat - rubbing down when dry

6 - Apply first and second top coat - rubbing down between the two coats
only

7 - DON'T apply each coat very thickly - you'll get lots of runs that will
be difficult to sort out.

If you are priming new, bare timber, give it two coats - thinning the first
cost to a 50/50 mix of paint and solvent.

Try not to thin the second primer, undercoat and gloss coats as you are
trying to get a good "body" of paint that will cover and last .

Always you the best quality paint that you can afford and try and paint the
work on a dry, cloudy, windless day if possible (nothing "flashes off the
paint quicker than a hot, sunny or windy day).

Cash







SS[_2_] July 12th 11 11:46 PM

How many coats of undercoat
 

"Cash" wrote in message
...
SS wrote:
Is there a limit to the amount of undercoats to put down before
applying a final coat of gloss.
One side of my porch gets hammered by the weather over winter and have
currently I have taken it back to the wood, so far I have given it 2
undercoats but wondering if there is any benefit by giving another
couple of coats before a final gloss.


SS,

Try two coats of undercoat and two coats of gloss (that usually gives me a
five year life on outside work) - but it is far more important to prepare
the surfaces properly first.

I.E.


1 - Rub down to remove all loose and denuded areas - ensuring that all
paint edges are 'feathered' and all sharp edges of wood have arrises
removed (slightly rounded)

2 - Repair any damaged areas properly (renewal, filler etc)

3 - Full prime or spot prime any bare or new timbers - and rub down when
dry

4 - Check priming work for missed or damaged work - and touch up as
necessary - light down when dry

5 - Apply first and second coats of undercoat - rubbing down when dry

6 - Apply first and second top coat - rubbing down between the two coats
only

7 - DON'T apply each coat very thickly - you'll get lots of runs that will
be difficult to sort out.

If you are priming new, bare timber, give it two coats - thinning the
first cost to a 50/50 mix of paint and solvent.

Try not to thin the second primer, undercoat and gloss coats as you are
trying to get a good "body" of paint that will cover and last .

Always you the best quality paint that you can afford and try and paint
the work on a dry, cloudy, windless day if possible (nothing "flashes off
the paint quicker than a hot, sunny or windy day).

Cash


Thanks guys, I have done most of the above but as the original paint was
badly flaking (I think gloss on gloss) I used a heat gun to remove it, then
sanded down.
Odd bits of bare wood in places with removing paint and went to get a primer
but found only primer/undercoat so used that. I have given 2 coats and in a
couple of bits retouched where underlying colour was showing through. I have
a pretty consistent overall white now.
Checking the weather and I have a 24 hour window of no rain so want to crack
on tomorrow with glossing.

I didnt thin the first coat of primer/undercoat but too late now. But have
gone for thin application coats.




jgharston July 12th 11 11:56 PM

How many coats of undercoat
 
SS wrote:
Is there a limit to the amount of undercoats to put down before applying a
final coat of gloss.


All of them. As to the *number* of undercoats, see the rest of the
thread.

JGH

[email protected] July 13th 11 06:49 PM

How many coats of undercoat
 

[snip]

I didnt thin the first coat of primer/undercoat but too late now.
But have gone for thin application coats.


After applying the initial primer coat/s it is customary to
then build up with undercoat which can be flatted back without
fear of losing protection, then apply two gloss coats.

You can apply several undercoat layers if required as it is the
undercoat finish you work in order to achieve the better finish.

Stephen.


--
http://www.stephen.hull.btinternet.co.uk
From the Wirral Peninsula.
Coach painting tips and techniques + Land Rover colour codes
"Whatever is rightly done, however humble, is noble". Henry Royce


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