Roger wrote:
 > How waterproof is the canvas in my '79 westy?  Also, what can I do to
make
> it optimally waterproof, i.e. any suggestions of spray-on products, etc?

My experience with poptop canvas:
Doing a lot of camping in the Pacific N.W., it became a regular habit to
waterproof and stainproof  the canvas on my westy. When you are out for a
week or longer, and drive around during the day with a soaked pop top, it
can mold really fast, and deteriorate the fabric.
Purists will argue canvas is supposed to absorb water, to close its fibers.
That is true. But if you sleep up there with the soaked canvas and rub
against it, the moisture will penetrate and make your sleeping bag
and whatever else it touches wet.
After a few days everything becomes damp and starts to mold.
Soon you find yourself with bleach and sponge trying to clean it all up and
damaging the canvas even more.
Guess it depends on your situation. If you camp in So.Cal. you won't need
any canvas protectant.
Also if you have a tall garage and camp a few days at a time, the canvas
can be dried out.
The canvas on my previous 81 westy became so weak from mold and bleach
that I became worried it would rip, and I would fall out of the upper bunk.

Imho it is okay to use protectant sprays on the pop top. On my 90 westy, I
use simple scotchguard fabric protector they sell in the supermarket.
The canvas deteriorates significantly less than on my previous camper
without any treatment.
The scotchguard makes the rain pearl off  the canvas,
and will help prevent stains from becoming permanent.
2 cans will cover the canvas. You probably can also use something else,
without any harm to the fabric. Most treatments lose their effect after a
few seasons.
Sorry this got so long.
Harald
90 westy.