Hi Phil!

Boy, you sure are "picky" (I'm just teasing), maybe my statement about
"pulling moisture" was incorrect...in fact, I know it was. It's exactly as
you state. What McDry cabinents do is "De-absorb" moisture...pull, de-absorb,
I guess it's all terminology...

I just know that the digital relative humidity indicators inside the
cabinents read 4% humidity almost all the time, and I recieved calibration
documentation from Seika that traced the meters to the ones that I have...so
they're accurate.

If you open the doors, of course the humidity level goes up. If you can keep
the doors open less than a minute, it'll recover back down to the original
level in about a hour or so....they say 30-minutes, but it does take a bit
longer than that...it all depends on your ambient conditions.

There are those of us that don't have a nitrogen cryogenic pad where we have
unlimited nitrogen...much less the piping that is required to plumb nitrogen
to the places that we would need it. This cabinent is great in my opinion,
there are a lot of positive things about these cabinents that is explained on
McDry's web page, they have have charts and everything, I think that these
are results from tests that they have done...why would I want to go back and
re-do these tests to prove them wrong?

I think they make a good product for those of us that don't have the resource
of unlimited nitrogen....I also think that there are certain aspects about
their cabinents that out-perform a dry nitrogen cabinent...

-Steve Gregory-

<< hi,

 I've got a problem with the statement that the desiccant 'pulls' moisture
out of the component...something that nitrogen can't do because it is a gas
that water isn't soluble in (see mcdry).  somebody help me with that one.

 as i see it, desiccant in the cabinet pulls moisture out of air in the
cabinet.  the moisture in the air in the cabinet gets there from the
component that has moisture in it.  The initial drying force is that of
moisture in the component migrating to dry air which then gets transferred to
the desiccant because of it's affinity with the desiccant (up to a point).

 now, replacing the dessicant-air combo with a continuous flow of desiccated
nitrogen should give you the same result.

 it seems to me the argument in favor of the mcdry is that it's more
convenient than dry nitrogen.  with the cost of electricity sky rocketing (at
least here in California) mcdry may not be less expensive (this is just a
guess).

 phil >>

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