Hi Keesbran,

Thanks for that article Very informative!
I'll have a go at some of those processes at some stage and post my results

One thing that was very useful in that pdf is the method he uses for affixing the paper to a substrate. (Gelatin on the paper, then glued down - releases in hot water. Genius!)

If you have any further luck using the diazo salts with the gum printing I'd love to hear...