I was curious as to how much sanding is usually necessary before priming.

Is it normal to sand old or even relatively new paint completely off before priming, or just enough so that the primer adheres?

I ask because I'm restoring some old artwork on a plywood cabinet, and if I don't sand it off completely it would be easier to restore the art by masking and going over it with each of the three or four colors originally used rather than to have to start from scratch.

The artwork was originally done in lacquer paint, however the paint I'm using to restore it is latex.

Thanks.

Darren Harris
Staten Island, New York.

On Sat, 1 Dec 2012 21:34:47 -0800 (PST),
wrote:

I was curious as to how much sanding is usually necessary before priming.

Is it normal to sand old or even relatively new paint completely off before priming, or just enough so that the primer adheres?

I ask because I'm restoring some old artwork on a plywood cabinet, and if I don't sand it off completely it would be easier to restore the art by masking and going over it with each of the three or four colors originally used rather than to have to start from scratch.

The artwork was originally done in lacquer paint, however the paint I'm using to restore it is latex.

Thanks.

Darren Harris
Staten Island, New York.


You want to take off enough to get a smooth coat of primer. It does
not have to be bare wood.

Paining over lacquer with latex is just repainting, not restoration.

wrote:
I was curious as to how much sanding is usually necessary before
priming.

Is it normal to sand old or even relatively new paint completely off
before priming, or just enough so that the primer adheres?

I ask because I'm restoring some old artwork on a plywood cabinet,
and if I don't sand it off completely it would be easier to restore
the art by masking and going over it with each of the three or four
colors originally used rather than to have to start from scratch.

The artwork was originally done in lacquer paint, however the paint
I'm using to restore it is latex.


No need to sand off old paint as long as it is adhearing well. Sand to
develop tooth, and to feather out any edges, as any edges will show through
the primer, and your finish paint. You do not need a very coarse paper to
develop tooth - 400 grit is plenty coarse enough.Blending edges may likely
require a coarser paper though. Since you are using latex, which is as
thick as snot, you probably won't have to blend the edges down to a level
you cannot feel, but you likewise will not want to leave unfeathered edges
either.

--

-Mike-

On Sat, 1 Dec 2012 21:34:47 -0800 (PST),
wrote:

I was curious as to how much sanding is usually necessary before priming.

Is it normal to sand old or even relatively new paint completely off before priming, or just enough so that the primer adheres?

Just enough to give it tooth for the primer to adhere, unless there is
paint flaking off. I'd sand all the flaky paint down and off the
cabinet. Sanding is usually done to flatten the piece for painting.
The glossier the paint, the flatter it has to be without showing the
blemishes.


I ask because I'm restoring some old artwork on a plywood cabinet, and if I don't sand it off completely it would be easier to restore the art by masking and going over it with each of the three or four colors originally used rather than to have to start from scratch.

The artwork was originally done in lacquer paint, however the paint I'm using to restore it is latex.

Lacquer is much, much thinner than latex, so you'll have lines at the
edges. Those can be sanded flatter (with a dual-action sander, or DA)
once the latex hardens completely. Then you can put a clear covercoat
over it all for a better look. I doubt you'll be able to match the
colors and glosses, so plan on painting the entire panel once you
start. Paint usually won't stick well to vinyl, either, so I'd avoid
that.

--
Happiness lies in the joy of achievement and the thrill of creative effort.
-- Franklin D. Roosevelt

On 12/1/12 11:34 PM, wrote:
I was curious as to how much sanding is usually necessary before
priming.

Is it normal to sand old or even relatively new paint completely off
before priming, or just enough so that the primer adheres?

I ask because I'm restoring some old artwork on a plywood cabinet,
and if I don't sand it off completely it would be easier to restore
the art by masking and going over it with each of the three or four
colors originally used rather than to have to start from scratch.

The artwork was originally done in lacquer paint, however the paint
I'm using to restore it is latex.

Thanks.

Darren Harris Staten Island, New York.


If whatever you're applying on top will stick to what's beneath it, you
don't need to sand down to wood. With many woods, whatever is already on
the surface is better to paint over than bare wood, anyway.

Smooth is relative with paint, as well. I can't tell you how many times
I've sanded a drywall patch "perfectly smooth" only to see the borders
after painting. If there's any texture or artwork on top, it often hides
those imperfections. But a single color, smooth topcoat will often show
them.

The solution might be building up a couple layers of primer with flat
sanding in between coats. Good auto-body guys are maters of this.


--

-MIKE-

"Playing is not something I do at night, it's my function in life"
--Elvin Jones (1927-2004)
--
http://mikedrums.com

---remove "DOT" ^^^^ to reply

On Sunday, December 2, 2012 12:50:47 AM UTC-5, Ed Pawlowski wrote:
Paining over lacquer with latex is just repainting, not restoration.

I'm not sure what you mean by that. As long as the surface is smooth the three different color matched latex paints I have, which are actually primer and paint in one, will be used on the entire side which was actually originally stenciled and sprayed. The base/background color, the second and then third color, followed lastly by the black outlines.

In fact, the most difficult part is the black outlines, which is really all I need to get right.

On Sunday, December 2, 2012 6:59:47 AM UTC-5, Mike Marlow wrote:
No need to sand off old paint as long as it is adhearing well. Sand to
develop tooth, and to feather out any edges, as any edges will show through
the primer, and your finish paint. You do not need a very coarse paper to
develop tooth - 400 grit is plenty coarse enough.Blending edges may likely
require a coarser paper though. Since you are using latex, which is as
thick as snot, you probably won't have to blend the edges down to a level
you cannot feel, but you likewise will not want to leave unfeathered edges
either.

Ok. I'm not 100 sure what you mean by "unfeathered edges". Is that were two different colors meet? I will obviously be using brushes. Foam for the main colors and a thick liner brush for the black outlines.

On Sunday, December 2, 2012 9:11:10 AM UTC-5, Larry Jaques wrote:
Lacquer is much, much thinner than latex, so you'll have lines at the
edges. Those can be sanded flatter (with a dual-action sander, or DA)
once the latex hardens completely. Then you can put a clear covercoat
over it all for a better look. I doubt you'll be able to match the
colors and glosses, so plan on painting the entire panel once you
start. Paint usually won't stick well to vinyl, either, so I'd avoid
that.

Ok. There is no vinyl involved in this project.

The paint I'm using is Valspar Interior Semi-Gloss, which is a paint and primer in one. I did ask for something to clear coat it with and was directed to get Valspar Clear Gloss Premium Enamel in a rattle can, which is supposed to seal and increase durability.

On Sunday, December 2, 2012 1:08:17 PM UTC-5, -MIKE- wrote:
If whatever you're applying on top will stick to what's beneath it, you

don't need to sand down to wood. With many woods, whatever is already on
the surface is better to paint over than bare wood, anyway.

In a question involving a different but similar project, *priming* over a clean, lightly sanded surface that still has paint is no problem, correct?

Smooth is relative with paint, as well. I can't tell you how many times
I've sanded a drywall patch "perfectly smooth" only to see the borders
after painting. If there's any texture or artwork on top, it often hides
those imperfections. But a single color, smooth topcoat will often show
them.



The solution might be building up a couple layers of primer with flat
sanding in between coats. Good auto-body guys are maters of this.

I don't want to lose the original artwork completely, since it will be my guide when re-painting.

But as far as sanding *after* I finish re-painting. Camn this be done without having to worry about bleed over?

Thanks a lot.

Darren Harris
Staten Island, New York.

wrote:


Ok. I'm not 100 sure what you mean by "unfeathered edges". Is that
were two different colors meet? I will obviously be using brushes.
Foam for the main colors and a thick liner brush for the black
outlines.


Unfeathered edges - the raw edge of the old paint. Imagine a large paint
chip missing - the edges of the chip. On a thin coat of paint that edge may
not be very significant but on a thicker coat it would be very significant.
You'd want to feather that down to blend it into the wood.


But as far as sanding *after* I finish re-painting. Camn this be done
without having to worry about bleed over?


Bleed over? Don't understand what you mean.

--

-Mike-

On Sun, 2 Dec 2012 12:33:34 -0800 (PST),
wrote:

On Sunday, December 2, 2012 12:50:47 AM UTC-5, Ed Pawlowski wrote:
Painting over lacquer with latex is just repainting, not restoration.

I'm not sure what you mean by that. As long as the surface is smooth the three different color matched latex paints I have, which are actually primer and paint in one, will be used on the entire side which was actually originally stenciled and sprayed. The base/background color, the second and then third color, followed lastly by the black outlines.


When you "restore" something, you bring it back to original condition.
If you have a '55 Chevy and replace the chrome on the bumper with
silver paint, it is just painted, not restored. Replacing lacquer
with latex is not a restoration.

On 12/2/12 2:33 PM, wrote:
On Sunday, December 2, 2012 1:08:17 PM UTC-5, -MIKE- wrote:
If whatever you're applying on top will stick to what's beneath it, you

don't need to sand down to wood. With many woods, whatever is already on
the surface is better to paint over than bare wood, anyway.

In a question involving a different but similar project, *priming* over a clean, lightly sanded surface that still has paint is no problem, correct?


Not that I know of. Priming over a surface that has different,
contracting colors can help keep the top color even.


Smooth is relative with paint, as well. I can't tell you how many times
I've sanded a drywall patch "perfectly smooth" only to see the borders
after painting. If there's any texture or artwork on top, it often hides
those imperfections. But a single color, smooth topcoat will often show
them.



The solution might be building up a couple layers of primer with flat
sanding in between coats. Good auto-body guys are maters of this.

I don't want to lose the original artwork completely, since it will be my guide when re-painting.

But as far as sanding *after* I finish re-painting. Camn this be done without having to worry about bleed over?


I don't know what "bleed over" means, and I'm certainly no paint expert.
But I would never sand the final, finish coat of paint. Maybe some do.


--

-MIKE-

"Playing is not something I do at night, it's my function in life"
--Elvin Jones (1927-2004)
--
http://mikedrums.com

---remove "DOT" ^^^^ to reply

On Dec 2, 3:40*pm, "Mike Marlow" wrote:
wrote:

Ok. I'm not 100 sure what you mean by "unfeathered edges". Is that
were two different colors meet? I will obviously be using brushes.
Foam for the main colors and a thick liner brush for the black
outlines.

Unfeathered edges - the raw edge of the old paint. *Imagine a large paint
chip missing - the edges of the chip. *On a thin coat of paint that edge may
not be very significant but on a thicker coat it would be very significant.

On Dec 2, 4:58*pm, Ed Pawlowski wrote:
On Sun, 2 Dec 2012 12:33:34 -0800 (PST),
wrote:

On Sunday, December 2, 2012 12:50:47 AM UTC-5, Ed Pawlowski wrote:
Painting over lacquer with latex is just repainting, not restoration.

I'm not sure what you mean by that. As long as the surface is smooth the three different color matched latex paints I have, which are actually primer and paint in one, will be used on the entire side which was actually originally stenciled and sprayed. The base/background color, the second and then third color, followed lastly by the black outlines.

When you "restore" something, you bring it back to original condition.
If you have a '55 Chevy and replace the chrome on the bumper with
silver paint, it is just painted, not restored. *Replacing lacquer
with latex is not a restoration.

I still don't see the parallel. I'll be using latex and a clear gloss
over that for protection. Many other have done this in restoring their
cabinets and the resulting artwork looks factory new.

Darren Harris
Staten Island, New York.

On Tuesday, December 4, 2012 9:54:06 PM UTC-5, Mike Marlow wrote:
Searcher7 wrote:

On Dec 2, 3:40 pm, "Mike Marlow" wrote:

wrote:



Ok. I'm not 100 sure what you mean by "unfeathered edges". Is that

were two different colors meet? I will obviously be using brushes.

Foam for the main colors and a thick liner brush for the black

outlines.



Unfeathered edges - the raw edge of the old paint. Imagine a large

paint chip missing - the edges of the chip. On a thin coat of paint

that edge may not be very significant but on a thicker coat it would

be very significant. You'd want to feather that down to blend it

into the wood.



The original paint was lacquer and therefore somewhat transparent. If

you sand it too much the color underneath the color you are sanding

stars to come through. It doesn't chip, so there are no unfeathered

edges to worry about.



But as far as sanding *after* I finish re-painting. Camn this be

done without having to worry about bleed over?



Bleed over? Don't understand what you mean.



When one color contaminates an adjoining color.





Got it. You meant bleed through. As for sanding after re-painting... you

can if you use a fine grit and are careful how much you sand. Even a very

fine grit will cut through a top coat at some point, exposing the underlying

coats. That's not really bleed through though. Bleed through is when the

underlying colors are still (partially) visible through your undisturbed top

coat. Think - not enough top coat.

No. "Bleed through". When one color contaminates an *adjoining* color. I'm hoping the sanded particles from one color don't embed themselves in the adjoining color.

I'm sorry to have to ask - if you've already said why, but why is it that

you are thinking about sanding your finished top coat? There can indeed be

good reasons to do this, but it also depends on the paint in question. Not

all paints will shine if knocked down with sandpaper. Don't want to answer

your question incorrectly and steer you wrong.

I may decide to do more than one coat depending on how it comes out. I'd like the finish to be as smooth as possible.

Thanks.

Darren Harris
Staten Island, New York.

On Dec 2, 12:34*am, wrote:
I was curious as to how much sanding is usually necessary before priming.

Is it normal to sand old or even relatively new paint completely off before priming, or just enough so that the primer adheres?

I ask because I'm restoring some old artwork on a plywood cabinet, and if I don't sand it off completely it would be easier to restore the art by masking and going over it with each of the three or four colors originally used rather than to have to start from scratch.

The artwork was originally done in lacquer paint, however the paint I'm using to restore it is latex.

Only two things will stick reliably to cured lacquer -- lacquer
or shellac. Clean, scuff with 220 until no longer glossy.
Seal with clear dewaxed shellac (Seal Coat), scuff when
dry, and paint with whatever you like. The shellac will also
seal the masking tape edges to create sharper lines and
prevent paint from seeping under.

On Sunday, December 2, 2012 6:34:51 PM UTC-5, -MIKE- wrote:
On 12/2/12 2:33 PM, wrote:

On Sunday, December 2, 2012 1:08:17 PM UTC-5, -MIKE- wrote:

If whatever you're applying on top will stick to what's beneath it, you



don't need to sand down to wood. With many woods, whatever is already on

the surface is better to paint over than bare wood, anyway.



In a question involving a different but similar project, *priming* over a clean, lightly sanded surface that still has paint is no problem, correct?





Not that I know of. Priming over a surface that has different,

contracting colors can help keep the top color even.

I used a foam roller. One coat with horizontal strokes, the second with vertical strokes and the third with horizontal strokes again, and I can still couldn't completely get rid of the "parquet-like" pattern. So I hope when it is painted over it will look ok.

Smooth is relative with paint, as well. I can't tell you how many times

I've sanded a drywall patch "perfectly smooth" only to see the borders

after painting. If there's any texture or artwork on top, it often hides

those imperfections. But a single color, smooth topcoat will often show

them.







The solution might be building up a couple layers of primer with flat

sanding in between coats. Good auto-body guys are maters of this.



I don't want to lose the original artwork completely, since it will be my guide when re-painting.



But as far as sanding *after* I finish re-painting. Camn this be done without having to worry about bleed over?





I don't know what "bleed over" means, and I'm certainly no paint expert.

But I would never sand the final, finish coat of paint. Maybe some do.

I'll be force to use brushes at certain points and assume I'll have to deal with some streaks as a result, so I was thinking a light sanding might help. (Someone even mentioned using #000 steel wool to "feather" any slight raises).

Thanks.

Darren Harris
Staten Island, New York.