Leather Helm Crest: Part 12 Applying Gesso grosso

Here is what Cennini suggests you do to apply gesso to the leather structure.

1. size it two or three times
Done.

2. mix gesso grosso and lay it on in a thick paste, modelling it to the animal shape needed.
Done.

3."This done, take some gesso grosso ground with size, liquid and flowing, on a brush, and you lay it three or four times over this crest with a brush."
When I had moulded the gesso grosso paste onto the leather, I then mixed water with the remaining paste in the bowl and painted it over the damp gesso. It smoothed out the rougher lumps and filled any splits that had formed while the leather flexed. I was not going for a smooth finish, as I wanted to replicate a scruffy, hairy surface.

4. "Then, when it is quite dry, scrape it and smooth it down, just as you do when you work on panel."
I used some sculpture tools to remove any lumps and smooth the surface a little.

5. "Then, in the same way, as I showed you how to gesso with gesso sottile on panel, in that same way gesso this crest. When it is dry, scrape it and smooth it down;"
I applied a layer of gesso sottile with a brush, but made it pancake batter thickness. I think this is much thicker than was intended. Again, I did this so the plaster would 'catch' as it dried and pull into a textured surface to give more of a look like a wavy, bumpy coat of fur.

To make a smooth item, I would mix new gesso grosso immediately after adding the rough layer, making this second, smaller lot with less dry ingredients in the water. I would apply a thin coat with a brush, let it dry, mix a new batch, apply it etc., until there were three or four layers. I would use a rough cloth to rub down the damp gesso grosso where needed. I would also make my layer of gesso sottile much more aqueous and spend time 'polishing' the dry surface with a cloth on a chock.

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