Pastiglia
Sometimes, the flat surface of the gesso isn't quite enough
Pastiglia is using gesso or some similar material - lead white and egg white have been used together as pastiglia - to raise the ground so that it can be painted or gilded. Due to the rigid nature of gesso, it is not suitable for flexible supports such as canvas but is ideal for wood.
In framing, the wooden frame is gessoed and then pastiglia can be added as decoration to be gilded with the ground that it is sitting on either being gilded as well or painted a different colour such as black or blue.
On the panel, pastiglia can be used to give gilded areas texture or it can be used to change what is essentially a two-dimensional area into one that involves a third dimension.
In the section on
, you can see how gilding the pastiglia works. gilding Here, we are going to look at a slightly different application - one where the subject of the painting is invading the real world from her position in the 'other' world of images. In this case, the painting is on a commercially made wooden panel for a custom-made, hand-carved moulding, solid-oak frame that has a rebate so the panel is loose. Normally, the panel would be in a groove and the pastiglia would be applied the same as here but would not be as fragile as it would be supported by the panel which would not move.
These fingers need to go over the sill into the real world. Just painting them on the frame, 'Trompe l'Oeil' style isn't quite enough for what is needed.
Here, the fingers in the portrait have been painted in roughly so that the fingers on the frame can be built up with layers of gesso to form pastiglia. First of all, the areas to be built up are drawn in using graphite.
Next, a small gap has been introduced between the panel and the frame and a piece of grease-proof baking paper has been inserted to protect the painting.
Then, the gesso to build up the fingers.
This gesso has quite a high glue concentration so that it has a lot of strength. The gesso of the frame was made using a PVC of 1:1 on the dry glue and it is this sort of strength that is needed here.
More strength is needed because the gesso pastiglia is going to extend beyond the edge of teh frame's sill and into what is essentially free space when the panels isn't there.
Each coat of gesso needs to be applied such that air bubbles are not introduced and once the final layer is on, it needs to be given at least two days to dry out properly.
Once the gesso has had a day or two to set, you can shape it with riffler needle files like these.
Riffler needle files are like regular needle files except that they are bent into arcs. There are a lot of different cross-sections in a set from flats to triangular and square to circular.
Very carefully and remembering that it is time that you have on your side, take off the gesso that is not needed so as to form the shapes of the fingers as though they were reaching over the edge of the frame's sill.
Now that the gesso fingers have been formed, they can be sized with heat-bodied linseed oil, allowed to dry and then painted.
This is after the final painting, prior to varnishing. The fingers have been completed with a reiterative process of alignment and modification. You might notice that an extra finger is visible when comparing it to the initial plan at the top of the page.
One of the things that producing things like this will produce is some curious comments such as, 'Can I touch it?' and, 'that is weird in the second degree,' and similar. It is odd to look at because framed paintings are, by there very nature, a window into another world. The frame is real and the world on the outside is real - the world that we live in - but inside the frame, it is another world.
In the days where all frames were carved, the frames were silled because it was a 'window' into this other existence and windows have sills. However, with advances in woodwork, specially shaped planes were used to form the profiles of the mouldings used in picture framing and people started to have frames that had the same moulding on both rails as well as the stiles because it is easier and therefore cheaper to do it that way.
In the times of silled frames, trompe l'oeil was used, painting the sill of the frame as a continuation of what was inside it but that was flat. Here, the use of pastiglia literally adds another dimension to it all.
This is the panel, post varnishing. As you can see, the fingers carry the same marking as the frame which makes the panel itself, potentially independent.
This is the rebate side of the frame after painting, post varnishing but prior to rottenstone treatment. As you can see, the fingers are not supported by anything other than the frame.
The spring clip is what I used temporarily to hold the panel in place and will be replaced by a canvas clip padded with cork.
This is the front side of the frame after painting, post varnishing but prior to rottenstone treatment. As you can see, the fingers carry the same position of the final panel.
The finsihed paintging, mounted in its polychromy frame with pastiglia fingers, running over the edge of the frame's sill, edging their way into the real world's domain.
All images and original artwork Copyright ©2020 Paul Alan Grosse.