[TheForge] Winterizing the shop

[Bruce .]

I'm TRYING to get back to some metalworking, but with temperatures
sometimes dropping below freezing, recently, it became urgent to winterize
my garage shop so the heater can keep up.

I'd already put weatherstripping all around the big garage door, but since
that was probably the biggest heat leak, I insulated it with R-13
fiberglass, and covered that with a tarp. I plan to run horizontal rods at
the joints to support the fiberglass batts when the door is open -- so that
the door could, in principal, still be opened w/o destroying the
fiberglass.  But I'll get back to that later.

Then I insulated the small, which is a sheet of 3/4" plywood with 2"x3"
framing, also with fiberglass.  I still need to cover that with a tarp.
Next came the one remaining window, which I covered with shrink plastic to
block drafts.  (The other window houses my A/C.)

So, aside from a few repairs to the insulation of the roof, the last
significant heat leak was the roof fan.  It took some thought to come up
with a way to cover that reversibly, but I did it.  It worked so well that
I thought I'd share it:

I made a small door of 1/2" plywood and hinged it to the rafter on one side
of the fan vent opening, such that it could be closed and overlap the
opening by about 2" all around.  With the door in the closed position, I
mounted a pulley (with axis parallel to that of the hinge pins) such that
it slightly overhung the far edge of the door and stood proud of it.  I
then took a long tension spring (think: bungee cord or screen-door spring)
and ran it from the rafter to rafter, skipping the rafter with the hinges.

When closed, the spring stretches over the pulley and across the door about
30 inches (which was as far as was necessary with this spring to do a good
job of holding the door tightly closed).  Pulling down on a cord on the far
edge of the door pulls the door open, stretching the spring until the it's
open 90 degree, at which point the spring contracts, driving the door fully
open, up against a stop installed to keep the pulley from hitting the
insulation.  I glued some 2 3/8" foam board insulation to the top of the
door (when closed over the fan opening).  I may add some very soft
insulation to stop minor air leaks, if I feel it's necessary.

Pull it open, pull it shut.   It's a very elementary toggle mechanism that
works very well.   Simple is nice.

Bruce
NJ