Hey Ken, didn't
we use that Klenstone product at Yale? When you were doing the tests we
discovered the bifloride effect, or what was that? You
look.
luv
ya,
Leland
Are any of you stone guys familar with
Klenztone cleaning chemicals?
One of there products uses a special formula
of floride salts.
Mitch,
I'm quite familiar with the
materials and have used them to good effect but am a bit peeved about their
lack of truth in advertising. Despite the fact that the advertising states
that the chemicals contain no acids the flouride salts turn to hydroflouric
acid when they encounter water. According to my materials handbook
hydroflouric acid is used in cleaning cast iron castings by dissolving the
sand from the castings. What this means for sandstone I think should be self
evident. What it means to the Lincoln Memorial, I assume of granite, is
possibly less shocking. I would certainly NOT use it on limestone or marble.
What gets me with suppliers of chemical cleaning solutions is that they will
say that their materials were used in this place, or that, but they will not
tell you the truth of the long term results, or what is really needed to know
in order to do no harm. I feel that Klenztone is the worse of any in this
regard. In the past I've asked Klenztone (directly asked of Klenztone and NOT
of any of their suppliers who usually have no idea what they are selling) to
give us names of buildings where their products were used in order to revisit
the locations in order to determine if the masonry was acid burned, or not. It
is when manufacturers are not up front with their information that I begin to
suspect ALL of their marketing hype. The "no acids" caveat is one that will
catch out preservationists seeking a non-acidic cleaning methodology... well,
when you use their product it does look good. It has to be used with the same
care, skill and attention as would be used when cleaning masonry with any
acidic cleaner. But if your chemistry and science in the beginning exluded the
use of acids, then I think it a really lousy deception to pretend that acids
are not being used with Klenztone.
My first phone conversatin with
Martin Weaver was to ask him about Klenztone, and my naive remark that the
material contained no acids and I wanted to know how it could possibly clean
masonry. His comment, in brief, was that he did not know of any masonry
cleaners that would not contain acids. I went away imagining that he would
think I was a complete dolt. Some time later I spent an afternoon drinking ale
with him and Bobby Watt in a dive in Ottawa and found out Martin is a very
very nice guy, a bit hilarious in humor and an out-of-the-box free range nut
case.
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