Too tight tonneau

[David.H]

I have a tonneau made 20 or so years ago from heavy duck canvas, it has hardly been used and appears to have shrunk (got smaller anyhow!) Any ideas how to stretch it? It will ( just about) go on the car, but the stress is considerable...took 3 to heave it into place. I am worried that the lift a dots on the body will pull away! 
Will a good  soaking merely make it even tighter. ...?
 D

[Hedd_Jones]

I got the canvas roof of my old chummy to stretch by laying warm wet towels on it and gently pulling. Adding more warm water as it cooled.  Then wetting it thoroughly once erected and fixed to the screen. 

Ive a similar problem with a vinul tonneau on the current chummy.

[David.H]

Thanks for that Hedd. I recall teenage daughters getting into baths with jeans on to shrink them which was the opposite to what I want to achieve! Perhaps I will have a go outside in the sun. ....
D