piano cover on new finish

[Newton Hunt]

Hi Mark,

I am not a finisher but I have been around finishes and
finishers for a long time.  I do not have any direct
experience with the water born finishes though.

I have seen lots of damage to new finishes that was caused
by pressure, too soon, plastic drop sheets covering finishes
too soon, rubbing out too soon, too thick an application,
too thin an application, and all nature of other problems. 
I hope to never be a refinisher.

I do know that once pollies cure they are cured once and for
all, about 24 to 48 hours depending upon amount of hardner. 
Varnish dries from the inside out, lacquer dries from the
outside in, shellac gets too hard and there are numerous
exceptions to everything depending upon material, type
(Chinese, European, American, etc.) and everything else.

One thing is certain, lacquer and varnish continue to exhale
volatiles for months and years and change their hardness and
other characteristics throughout this process.  Some
plastics have volatiles that interact with lacquer and
lacquer can remain soft for months after application.

Caution is essential unless full understanding of all
factors is in place.

Error in the direction of caution.

		Newton

bases-loaded@juno.com wrote:
> 
> On Mon, 10 Jul 2000 10:54:00 -0400 nhunt@jagat.com (Newton Hunt) writes:
> > Not quite so.  Lacquer dries from the outside in and can
> > remain soft for weeks and weeks.
> 
> Hi Newton -
> 
> While theoretically this is possible, this would only be true if the
> finisher was in such haste that he literally "piled" on multiple coats of
> lacquer without adequate dry times between coats.  In a normal spray
> schedule, the finish can be safely rubbed out within one week (some even
> do so within 48 hours, although I would not recommend it) with no
> noticeable shrinkage after that point .  You can use any rubbing
> lubricant you wish.... oil, water, mineral spirits, naptha, etc.  with no
> harm done to the film.  In 30 days, it is hard to imagine the film still
> having a "soft belly", unless there was total disregard for prudent
> finishing practices.
> 
> Mark Potter
> bases-loaded@juno.com