Dan Becker wrote:
>
> >> Regarding Peel Away and problems
> >
> >I hate to keep pounding away against Peel Away because every product has
> >attributes that may be useful on some project, but...
> >
> >Peel Away 1 was used on the exterior woodwork of Blaine House (governor's
> >mansion) here in Maine. The result was dramatic and extensive failure of the
> >new coatings within two years.
>
> John, Brian, and others offering cautions:
>
> In these cases of failure, is there documentation that the neutralizer was
> applied according to manufacturer specs, including the litmus test for
> proper final pH, and the follow-up coatings still failed? The litmus test
> is a surface application, and if the Peel-Away is allowed to remain on the
> surface beyond the minimum time necessary to remove the paint film, then is
> seems reasonable to expect that it will internally penetrate the porous
> wood to leave residual chemical content to leach out later. I'd be
> interested to know if in these cases, whether allowing the neutralizer to
> similarly soak into the wood substrate would be sufficient to adequately
> compensate.
>
> Regards
>
> ______________________________________________
> Dan Becker, Executive Director "What's this? Fan mail
> Raleigh Historic from some flounder?"
> Districts Commission - Bullwinkle J. Moose
>
> [log in to unmask]
=====================
Dan:
> interested to know if in these cases, whether allowing the neutralizer to
> similarly soak into the wood substrate would be sufficient to adequately
> compensate.
Why change the surface chemistry from one extreme for its opposite
extreme? It will still lead to a less than desirable result.
One of the first questions you need to ask, is how clean is clean, or
how stripped is stripped?
If a paint film is being removed to accomplish a more pleasing painted
finish then there is no reason to remove all the paint especially not
the prime coat. In this case, the target is to remove only enough paint
to achieve the required result.
If paint is being removed in order to determine ghosting and historic
evidence then again the primer will remain. In both cases, absorption
by the substrate should not a big issue.
Then again why risk the problem.
If you specify that absolute monitoring of the chemistry of the
substrate is required and you select the highest price, then there may
be enough labor hours in the project of have someone baby-sit the
caustic stripper and try to properly neutralize. Now, just to make sure,
state in your specifications that proper neutralizing means, allowing
the surface to sit for a time after stripping and neutrilizing to allow
the two competing chemicals to fully interact. State that this must be
done to be sure that one chemical is not in more abundance then the
other. This condition may not show up for some time. How long can the
project sit un-painted before the concern about surface deterioration
that leads to paint failure is an issue? How much water can the surface
tolerate before the raising and feathering of grain become an issue that
doubles the labor on the project?
Now, if the object is to remove all paint in order to have a non-painted
surface, concerns for chemicals being absorbed into the substrate is a
real issue. Take everything that was previously stated and implied and
repeat is a few times and in a few different variations.
In any case, why use a stripper that requires neutralizing? Why deal
with that issue at all? It is not possible to achieve a paint free
surface on a porous material without some bare substrate having chemical
on it for some dwell time.
As a general rule, strippers that require neutralizing should not be
used.
(Remember, all rules have exceptions,)
The short answer to the question, 'interested to know if in these cases,
whether allowing the neutralizer to similarly soak into the wood
substrate would be sufficient to adequately compensate.' is NO.
Thoughts from a wood butcher,
Bryan
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