[ARC5] Old Dynamotors- Don't be a DooFuss Like Me....

[Todd, KA1KAQ]

On Mon, Apr 1, 2013 at 12:50 AM, David Stinson <arc5 at ix.netcom.com> wrote:

>
>
> I thought about putting the whole thing sans end bells into a 200-degree
> oven for a couple of  hours to dry it out
>

This is  a problem with big chunks of iron in old transmitters, too. Many
do not realize how similar to a sponge the laminations and windings are.
And old transformer left sitting in a damp cellar or storage shed is an
accident waiting to happen if you just haul it out, hook it up, and apply
voltage. Might happen in 5 seconds, 5 hours, or 5 days, 9.9999 times out of
10 it'll zorch.

The oven works great as is provides a means of getting rid of the moisture
without introducing more. On bigger pieces it can take a day or two, maybe
more, to feel safe enough to put power to it. And there's never a
guarantee, of course. But recovery rate is far, far better when dried out
than when not. The trick is to heat it up long enough for the heat to reach
the core and drive out the moisture. It's all about the mass. Smaller =
faster; hours vs days.


A good reminder as many of my dynamotors are out in the garage here in
humid NC. Though lately humidity has been amazingly low.

~ Todd,  KA1KAQ/4