How can I make a really wide paint roller like 15-20';?

I am working on a project that requires me to use a really wide paint roller. basically like a regular paint roller (9';) just wider.. I would even use something that rolls like a paint roller.. could be a tool or some sort..How can I make a really wide paint roller like 15-20';?
Why try to make one when you can buy a ready made one? Most paint stores that cater to professional house painters sell over-sized paint rollers. I think they are 18'; wide but I may be wrong. I just know I've seen them for sale at places like Sherman Williams. Try calling around at your local paint supply stores to see who sells these.How can I make a really wide paint roller like 15-20';?
go to the local art supply store (or anyplace that sells anything that comes on a long cardboard tube) and ask for one of the cardboard tubes that support the rolls of canvas (very very thick and strong), cut it to any length you like, wrap it with a thin sheet of foam rubber, cheap flat weave carpet or fleece fabric cut to fit- glue it down with ';liquid nails'; from the hardware store and put spindles in the ends with a modified broom or mop handle. You can make any size you want.