I purchased a gel plate a few months ago and have been experimenting with it on and off for a few months. I was inspired by Yeates Makes, and have been trying to replicate his image transfer method. However, unlike him, I don't have acrylic print medium, and due to my art material collection already being cramped I don't want to buy any. Instead I have slowly been trying to get image transfer to work with my large supply of black tempera.

A summary of how gel transfer with proper medium normally goes

We either take a printed positive, or create one using oil based mediums, such as crayons. We then apply a film of print medium to the gel plate. After a moment of drying time, the positive is lightly pressed into the gel plate. The paper absorbs print medium while the positive is mildly hydrophobic and does not. Thus when our positive is removed it leaves behind a duplicate image, that can then be absorbed onto a plain sheet of paper. In order for this technique to work the medium cannot dry on the plate. If it did it wouldn't stick to the blank sheet. Thus we need a medium with a long working time, or we need to apply a fresh layer on top after allowing the first layer to dry on the plate. then we can pull both layers while still wet.

since, in principle, the positive doesn't absorb ink in the waxed areas it should be re-usable a number of times (on the order of 4).

A summary of tempera attempts

The first problem I encountered was that, un-modified, the tempera I used will bead on the plate rather than coating it. I was able to fix this by adding an emulsifier to the tempera. I happen to have a large amount of gum acacia from ink making experiments a few years ago and so opted for that. The thickened, emulsified tempera coated the plate without issue.

The next issue was that the oil pastels I first used didnt seem to be hydrophobic enough, or at least there wasnt enough contrast between my supposed whites and blacks since the paper doesn't perfectly absorb everything. I tried wetting the positive before applying it but that proved innefective. While some gel printing tutorials reccomend wetting the sheet I found that with the lightweight sheets I was using, the swelling caused the paper to bubble across the plate and thus have such an even contect no image could be reliably produced. Instead I found that the major problems I had were that I had applied too much pressure to the positive, forcing waxed sections to take up ink, and that the tempera was drying too fast and thus not fully picked up onto the blank sheet.

I tried wetting the receiving sheet, but like before, the buckling and swelling of the paper got in the way. I tried going faster and that had some success but i found the positive was just too absorbent. Instead I took another page from Yeates Makes and applied a second layer of clear medium made from gum acacia and water, which allowed me to pull everything from the plate. This can work great in most cases, but because it so effectively pulls from the plate, if the positive doesn't absorb enough ink, the whole page will be dark, though the image is still intelligible. The gum acacia also creates a glossy surface finish which is not neccessarily good or bad but should be noted.

It's also crucial to give the print enough time to dry onto the blank sheet from the plate. If pulled prematurely most of the image will be left on the plate.

using white pigment rather than clear as the second layer may help improve contrast.