I need to build an entry door for a small astronomical observatory that
I am constructing in Maryland. The door will be only 32-1/4" wide by
45" tall (as the wood-frame base upon which the telescope dome will
rest is only 48" tall).
I would like for it to be a frame-and-panel door (two vertical panels)
of solid mahogany.
The problem is that the door exterior will be fully exposed to the sun
and elements. It will face southward, getting the sun all day long.
Summer-winter temperature changes are fairly extreme in Maryland.
My concerns are water getting into the joints where the panels rest in
the grooves and finding a finish that will stand up to the sun. I used
a very expensive spar varnish when I refinished an exterior wood door a
few years ago and it lasted about a year.
Advice most welcome.
Davoud <http://www.davidillig.com/observatory.shtml>
--
usenet *at* davidillig dawt com
In article <260420040732162111%[email protected]>, Davoud <[email protected]>
wrote:
> I need to build an entry door for a small astronomical observatory that
> I am constructing in Maryland. The door will be only 32-1/4" wide by
> 45" tall (as the wood-frame base upon which the telescope dome will
> rest is only 48" tall).
>
> I would like for it to be a frame-and-panel door (two vertical panels)
> of solid mahogany.
>
> The problem is that the door exterior will be fully exposed to the sun
> and elements. It will face southward, getting the sun all day long.
> Summer-winter temperature changes are fairly extreme in Maryland.
>
> My concerns are water getting into the joints where the panels rest in
> the grooves and finding a finish that will stand up to the sun. I used
> a very expensive spar varnish when I refinished an exterior wood door a
> few years ago and it lasted about a year.
>
> Advice most welcome.
>
> Davoud <http://www.davidillig.com/observatory.shtml>
What brand of spar varnish did you use? UVA Spar Varnish by
Pratt&Lambert or McCloskey is highly recommended.
Your error may have been a failure to dilute then progressively
concentrate the varnish: first coat is 20% varnish:80% naptha or mineral
spirits; second coat is 30% varnish:70% naptha/m.s.; etc until you're at
100% varnish.
Make sure the panels "float." i.e. 1/4" edge of panel into 5/16" slot in
stiles and rails...
It will last forever...particularly if you remember to finish the bottom
and top horizontal surfaces of the door most especially.
--
Doors - Locks - Weatherstripping
POB 250121 Atlanta GA 30325
404/626-2840
Seems like you are just asking for deterioration with a frame and panel door
under those conditions. Why frame and panel? Why not build a solid door
with no grooves/cracks for moisture to sneak in? I'm not sure what finish
to use, but something used on wooden boats seems appropriate.
Bob
"Davoud" <[email protected]> wrote in message
news:260420040732162111%[email protected]...
> I need to build an entry door for a small astronomical observatory that
> I am constructing in Maryland. The door will be only 32-1/4" wide by
> 45" tall (as the wood-frame base upon which the telescope dome will
> rest is only 48" tall).
>
> I would like for it to be a frame-and-panel door (two vertical panels)
> of solid mahogany.
>
> The problem is that the door exterior will be fully exposed to the sun
> and elements. It will face southward, getting the sun all day long.
> Summer-winter temperature changes are fairly extreme in Maryland.
>
> My concerns are water getting into the joints where the panels rest in
> the grooves and finding a finish that will stand up to the sun. I used
> a very expensive spar varnish when I refinished an exterior wood door a
> few years ago and it lasted about a year.
>
> Advice most welcome.
>
> Davoud <http://www.davidillig.com/observatory.shtml>
>
> --
> usenet *at* davidillig dawt com