This did last a while as well, but finally full colour A3 gumprints seem to be coming out alright. It would have seemed that we are talking nothing too difficult; only one size larger than the popular A4 format. Nothing more deceptive. It turns out, that increasing the size by one step increases the level of difficultly out of proportion. A tiny gum, say 13×18 or 18×24 is not much o a challenge, though more than in the case of most other alternative processes. Of course, relatively not much of a challenge as the gumprint is in itself a demanding technique, especially if your aim is to get good colour and you need to put together a number of layers.
When we get to full A4 and then larger sizes, problems mount. Even well prepared, pre-shrunk paper will shrink some more if allowed to dry freely. Of course, the better the preparation, the less it will shrink, but eliminating this problem entirely is a true challenge. In a monochromatic image this shrinking will translate into slight lack of sharpness that can actually be beneficial giving the gumprint its characteristic, slightly unreal appearance. In a full colour print, however, we will get the ugly appearance that we get in offset printing when plates are not aligned properly.
The strength of forces working in the paper while it shrinks also grows with size so it is more and more difficult to counter them mechanically. A large sheet will either break whatever holds it in place or snap into two. Of course, all the errors coming from the fact the size of paper is changing will be more pronounced. If a small sheet shrinks by a fraction of a milimetre which will not really be visible, a big sheet may shrink by say 5 milimetres and this can’t be hidden in any way.
I had an opportunity to appreciate all these difficulties when working with A3 gumprints. They didn’t come out well at first and I had an opportunity to understand why most people only show smallish gumprints such as the famous Blue Flask and why A4 is considered a pretty big size. Only that I have a problem with limitations and I expect the size of my prints to result from aesthetic considerations not technical limitations.