Prepping old primer for paint

[Theweekendwarrior]

Hi All,

 Sorry for the recent influx of posts but Im running out of good weather here in NE and can use all the help I can get! As always the any advcie is graetly appreciated.

My situation is as follows: In past years especially the previous I did a bunch of priming on my home but never made it to paint because of the weather (oldest primer is 2 years old if this has any bearing; its oil-based primer). This year I'm going to finally get to the painting portion but want to make sure its ready. Is there any preparation that should be done before painting (ie washing or sanding/roughen-up) that would promote better adhesion than being left as is?

I started using oxi-clean as a cleaning solution mainly because of the low cost. It does a good job especially with the mildew. Are there any down-sides to using this oxygen bleach based product?

Thanks again,
ww

[chrisn]

Just make sure it is clean and dry
re prime with a slow dry QUALITY oil primer
apply top coats

[rmichael]

WW,

Re-priming may not be necessary with the oil primer, the cleaning should open it up for the top coat. It just needs to be clean and dull... 
There should not be any issues using the Oxi-clean.. just rinse well.

Best Luck,
rmichael

[Theweekendwarrior]

How would i go about dulling the primer?
 Would sanding with 220 paper do this?

Im using BM penetrating primer, I feel that doing 2 lights coats gives me better results so Ive been do it this way. So once the second coat dries it is usually pretty glossy. Is this normal?



Thank you both for the replies!

[chrisn]

For me, after 2 years,I would re prime.
Maybe you don't have to, but I would not feel comfortable not doing it.
One coat is all you need and yes, it might be a little glossy, make sure it is mixed WELL.

[VJ1]

The technical data sheet for BM exterior penetrating primer instructs that the top coat be applied within a reasonable length of time, preferable no longer a month. Seeing that the primer has been exposed to the elements for two years, I would highly recommend cleaning and mildew treating properly, then re-prime and finish coat within a few days.
Vandi.

[rmichael]

The technical data sheet for BM exterior penetrating primer instructs that the top coat be applied within a reasonable length of time, preferable no longer a month. Seeing that the primer has been exposed to the elements for two years, I would highly recommend cleaning and mildew treating properly, then re-prime and finish coat within a few days.
Vandi.

I would think that the "reasonable length of time" recommendation from the data sheet assumes the accumulation of dirt and mildew over an extended time. IMO cleaning to remove dirt, mildew and any oxidation from the oil primer should provide a suitable surface for painting. Of course there is also the option of re-priming if the primer has washed out and degraded from the elements... If re-priming boosts your confidence there is certainly no reason not to re-prime... 

[chrisn]

Why chance it??

re prime, after 2 years to primer has begun to degrade anyway
re prime it

[rmichael]

ASAIC... EOM.. 

[Theweekendwarrior]

Thank you all! What does asaic eom mean?

[rmichael]

Thank you all! What does asaic eom mean?

It's a really good exterior primer.... Just Kidding    I saw no need to carry on a debate with Chris about priming or not priming but the acronym has a typo... AFAIC... As Far AS I'm Concerned.... EOM..  End Of Message.
But don't hesitate to post your questions, I was just messing with Chris... who is really a very knowledgeable member...   

Best Luck with your Project,
rmichael

[Theweekendwarrior]

Ok. Do either of you think that by roughing it up with 120-220 grit sandpaper would allow me to bypass the reprimin step? It is a thick coat of primer.

Thanks again.

[chrisn]

That will probably work out OK.
Even though rmichael is probably correct, if it were me doing my home or someone was paying me to do it, I would still prime it again. It does not take that long and I would sleep better at night.As I said, that's just me. take it or leave it.

[Theweekendwarrior]

Thank you both very much!

In the event that I reprime, should I just put on a thin coat? And considering some of this old primer was applied heavily, is the thickness of the coat a concern? I found an usda article that says optimally the finish coats of paint should be between 3-5 mils. So Im wondering if there will be any downfalls if the primer is applied to heavy?


As a side topic would it be ok to prime over solid latex stain with this long oil primer (BM penetrating primer) or do I need to strip it


Thanks again.

[chrisn]

All that is needed is one regular coat over all, not thick or thin, with two regular finish coats.