Well, lots of answers. The room at school is 45% which is about 8% MC.
What wasn't mentioned is that dehumidifiers ice up so fast under about 50
degrees F that they're essentially worthless.
"Tony B" <[email protected]> wrote in message
news:[email protected]...
> I've recently aquired a de-humidifier in an attempt to stop my tools and
> machines going rusty during the winter - what's a good relative humidity
level
> to aim for so I don't make the air too dry for all the wood in the
workshop?
> Many thanks
> Tony
>
"Tony B" <[email protected]> wrote in message
news:[email protected]...
> I've recently aquired a de-humidifier in an attempt to stop my tools and
> machines going rusty during the winter - what's a good relative humidity
> level
> to aim for so I don't make the air too dry for all the wood in the
> workshop?
> Many thanks
> Tony
>
The perfect humidity is exactly the same as the environment your project is
going into when complete. 40% to 50% is considered good for the hmans in
the house.
"Tony B" <[email protected]> wrote in message
news:[email protected]...
> I've recently aquired a de-humidifier in an attempt to stop my tools and
> machines going rusty during the winter - what's a good relative humidity
> level
> to aim for so I don't make the air too dry for all the wood in the
> workshop?
> Many thanks
> Tony
Actually if you can control the wide sudden temperature changes it may help.
My tools are always subject to humidity in between 25 and 100% and do not
have rust problems. That plus TopCote.
On 2 Dec 2004 14:59:01 -0800, Tony B <[email protected]> wrote:
>I've recently aquired a de-humidifier in an attempt to stop my tools and
>machines going rusty during the winter - what's a good relative humidity level
>to aim for so I don't make the air too dry for all the wood in the workshop?
>Many thanks
>Tony
In my shop, er, studio, the temp ranges from 60F to 75F and the RH
from 50 to 70.
Right now, the temp is 65 with a RH of 60. At the peak of summer, the
temp might reach 75 for a short while and if I didn't run the
dehumidifier it'd reach around 90, but I keep it at about 60.
Obviously right now the dehumidifier isn't running. My furnace is a
condensing type, that does a good job of further wringing out already
dry air.
Check out "Understanding Wood" by Hoadley for a discussion on
temperature, relative humidity and grains of moisture in the air.
What this means is that if the water content of the air is unchanged,
the RH will rise and fall opposite the temperature. The temp rises,
the RH falls. The temp falls the RH rises. Of course if the temp is
unchanging, if the RH rises there's more moisture in the air, if it
falls, less. But that's obvious.
Probably more than you asked for.
On 2 Dec 2004 14:59:01 -0800, Tony B <[email protected]> wrote:
>I've recently aquired a de-humidifier in an attempt to stop my tools and
>machines going rusty during the winter - what's a good relative humidity level
>to aim for so I don't make the air too dry for all the wood in the workshop?
>Many thanks
>Tony
As Leon has so perspicaciously stated, it is not so much the relative
humidity as it is the relationship of the highs to the lows, and the
swiftness with which they occur.
What will really rust your tools is a cold front, precipitously
followed by a warm front (that happens to be carrying a lot of
moisture, as is their nature.)
Unfortunately, the reverse is also true.
If you simply allow your tools to live at the ambient air temperature,
and only bring them up to working temperature in a gentle way - you
will be fine.
Wood does not react as quickly to temperature/moisture changes as cast
iron, so they will be just fine ( and prolly achieve closer to the
ideal mc ) if left alone.
Regards,
Tom.
"People funny. Life a funny thing." Sonny Liston
Thomas J.Watson - Cabinetmaker (ret.)
tjwatson1ATcomcastDOTnet (real email)
http://home.comcast.net/~tjwatson1