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Jay Chan Jay Chan is offline
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Default Fixing Particle Board That Has Raised Grain Excessively

On Apr 25, 3:15 pm, Jay Chan wrote:
I have mistakenly applied water-based latexprimeron myparticleboardbook case that I am building. Now the areas where I have
applied water-based latexprimerhave raised grain excessively. I
have tried sanding the raised grain. But I can only sand away the
high spots, and I cannot sand enough to remove the low spots (primer
keeps clogging the sand paper doesn't help either).

Yes, I should have used oil basedprimer. I have applied oil baseprimerin one small area of the book case, and it turns out very nice
after I have sanded the area. But this is too late now because I have
already used the water basedprimeron most of the book case. I
cannot turn back the clock, I need to find a way to "fix" the problem.

I can try aggressively sanding the surface. But I am afraid that the
sandpaper will keep clogging. And the heat that will generate from
aggressive sanding may not be good for theprimer.

I can paint several more coats of latexprimer, and hope this I will
fill up the low spots. But I am afraid that this is just wishful
thinking. Theprimermay simply follow the ups and downs of the
surface, and I may just waste my time.

I can use chemical to remove theprimer, and do this over again. But
I am afraid that the chemical may raise the grain even more.

The only way that I can think of is to use a scrapper to manually
remove theprimer, sand out the raise grain, and re-prime with oil
basedprimer. But I think this will be the last resolve.

Is there a better way to deal with this problem?

Thanks in advance.

Jay Chan


I finally fix the problem by doing these:
o Applying two coats of oil based primer over the latex primer
while making sure that I place the surface horizontally.
o Sanding the surface using 100 grit sand paper.

When I sanded the latex primer, I kept having the sand paper clogged.
Oddly, this time I don't have this problem when I sand the oil based
primer. Not sure if this is a difference between oil based primer or
latex based primer, or this is a difference between a new primer and a
1-year old primer.

I still need to touch up and sand some areas that are more troublesome
than the rest. But now I can see the end of the tunnel.

Jay Chan