🚀 go-pugleaf

> I have some old pine chests that were bought unfinished (about 10 years
> ago).  They were stained and varnished for many years.  About four years
> ago, I sanded them down to the wood, and painted them with white oil-based
> enamel (PPG).  Now I have a problem with the knots bleeding through as a
> brown discoloration (this takes a few months to show up after painting).  
> I have repainted them twice now, with the same results.

The recommended technique for painting over knows is to first paint the knots
themselves with shellac, maybe two or more coats, then, after the shellac has
dried, paint the rest of the cabinet. The various constituents of the sap in
the knot (like crude forms of turpentine, and the like) can easily bleed
both oil-based and latex paints, but an alcohol-based coating, such as shellac,
seems to cure the problem. 

I have used this technique successfully even on outdoor trim, with no bleed-
through after several years of exposure.

Dick Pierce

In article <872@hercules.UUCP>, barrys@hercules.UUCP (Barry Steel) writes:
> ...Now I have a problem with the knots bleeding through as a
> brown discoloration (this takes a few months to show up after painting).  

Yep, knots will get you every time.  I recently repainted my house
(see previous posting on paint removal techniques), but found that
I had to replace about 10% of the pine siding.  I knew about the
knot problem and asked around the paint stores for the sure-fire
cure.  The cheap and effective solution is shellac.  Sand your paint
off - down to the knot.  Put 2 coats of shellac over the knot, and 
repaint.  Works like a charm.  Oh yes - the same technique works for
water stains on sheetrock ceilings (where the H2O leak has made that
nice yellow spot).  Same thing is true - the spot will bleed through
new paint *unless* you seal it up with shellac.  Don't ask me why...
...maybe it's a law!

--
	Of all the things I've lost, I miss my mind the most.

Michael L. Begeman              Microelectronics and Computer Technology Corp
Software Technology Program     Austin (where the sun always shines) Texas

uucp:	{ihnp4, seismo, harvard, gatech, pyramid}!ut-sally!im4u!milano!begeman
arpa:	begeman@mcc.ARPA

In article <872@hercules.UUCP>, barrys@hercules.UUCP (Barry Steel) writes:
> ... Now I have a problem with the knots bleeding through as a
> brown discoloration (this takes a few months to show up after painting).  
> I have repainted them twice now, with the same results.

There is a product on the market called 'Kilz' which is supposed to
prevent bleedthrough problems like this.  It is a primer-type material,
so you can paint over it.  I've not used it myself, but others I know
have recommended it.
A local hardware store should have it.

-- 
Charles Sandel
    arpa: sandel@mcc.arpa
    uucp: *!ut-sally!im4u!milano!sandel (or  *!ut-sally!charles)
An endangered species: native Austinite

> I have some old pine chests that were bought unfinished (about 10 years
> ago).  They were stained and varnished for many years.  About four years
> ago, I sanded them down to the wood, and painted them with white oil-based
> enamel (PPG).  Now I have a problem with the knots bleeding through as a
> brown discoloration (this takes a few months to show up after painting).  
> I have repainted them twice now, with the same results.
> 
> I would like to get them right, but I obviously need to do something
> different.  Help!  My only ideas are:
> 
> 	1) lightly sand, *primer* and repaint,
> 
> 	2) use latex
> 
> 	3) make kindling.  :-)
> 
> 
> barry steel



Sand them down and seal them with yellow shellac ... two coats  ... lightly
sand between coats and before painting.