I made my first framebag for the groundsheet of an old tent. It was some kind of ripstop plastic. It was kinda scrappy, but did the job well enough. It wasn't designed to be waterproof, but managed to keep the water out fairly effectively due to the material.
hsttp://www.flickr.com/photos/74188980@N08/7124045655The second framebag was a partial one, made from the back of an old suit case, as you say. When working with thicker foam material, it's important to consider the thickness of the metrial and take that into account when planning measurements.
http://cyclocaust.blogspot.co.uk/2013/11/partial-framebag-diymyog.htmlI also made a handlebar harness, with plastic sheets and external material from a different suitcase. The spacers pushed up against the bars were stacked layers of section cut from a foam suitcase. I'm goign to modify this one to change the lower structure though.
http://cyclocaust.blogspot.co.uk/2013/12/handlebar-harness-barness-diymyog.htmlEvery zipper I've ever used for a project has been scavenged from something else. Inner tube is also a really useful material - you can put sections of it against where the fabric contacts the bike - the rubber will provide more friction against the material and reduce slipping. This is especially useful on the attachment straps.
I've always found that a stitch can look ugly as hell, but work very well. Getting things looking neat can be more difficult than getting them to work.
