> 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?

I have kept my poptop open during severe rain on all four of the Westies
I've had over the years.  The canvas got very wet, almost translucent, but
did not allow any water into the bus.  This was without any additional
waterproofing.  If it was still raining when we shut down camp, we just
closed the top, drove to our next destination, and then re-opened it to dry
as soon as possible.  Probably not the best thing for canvas longevity, but
if you can't use your Westy as shelter when camping in the rain then what
good is it as a camper?  I have heard of using tent waterproofing on the
canvas, but such treatments tend to affect the breathability of fabrics, and
since the untreated canvas was suiting me fine I saw no reason to even
bother with it.  Of course, the canvas on all of my campers was in generally
good shape; if yours is dryrotted (or ripped) your experience may differ.

- Ron Salmon
 The Bus Depot
 http://www.busdepot.com
 (215) 234-VWVW