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DerbyDad03 DerbyDad03 is offline
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Default MDF, Wipe On Poly, and a Deteriorating Finish

On 14 Aug, 06:44, "Dave Gordon" d@p wrote:
"DerbyDad03" wrote in message

oups.com...





A few weekends ago I built a prototype of a low-slung entertainment
center out of MDF. SWMBO wanted a visual of the size and shape before
I commited time and funds to the actual item. Sort of like this, but
with no drawers or doors on the prototype:


http://www.sauder.com/images/drawing...nza_401111.jpg


Since building the real one is going to be my winter project, I
figured I would finish the MDF with a couple of coats of wipe-on poly.
Now, a few weeks later, I am beginning to see spots and areas where
the finish is turning white and other areas where the surface is
cloudy and rough.


I store CD's on one shelf and the finish under the CD's is white and
rough. There's a rough, cloudy spot under the DVD player where it
looks like something dripped on it, but there's no way that could have
happened - it's *under* the player. One exterior side has spots that
look like something splashed on it, but it's on a rug with the side
facing a area where no liquids would have been present.


It looked fine (well, fine for an MDF entertainment center!) for a
couple of weeks and then I noticed these imperfections in various
areas. Any idea what might be happening?


Since you're in the market for suggestions, I have a theory.

Perhaps your wipe-on poly hadn't finished outgassing (or even the MDF), and the CDs prevented proper
ventilation to allow the evaporant (is that a word?) to properly boil off.
Under your CD player, perhaps some heat radiated downwards and did some damage to the surface.- Hide quoted text -

- Show quoted text -


-- Perhaps your wipe-on poly hadn't finished outgassing (or even the
MDF)

That theory has always been in the back of my mind. I let the final
coat dry for about 24 hours and then moved it to the living room and
loaded it it up. You could smell the poly for a few days afterward. I
could tell you the whole saga of my kid's HS graduation, the out-of-
town guests, the new living room furniture, etc. but suffice it to say
I was was rushed and had to get it set up AQAP.

I'll call that theory the winner. Thanks!