Friday, 28 August 2020

Vatican courier chess, part 2 - the board

Just some note before this post really starts. Blogger did change its layout lately, to make it more compatible with mobile phones. This had the side-effect of making blogposts much harder for me, and not being able to present the contents in an agreeable way. I even began thinking to quit the blog. Blogger mentioned that there was a revert option to the old style, but this was nowhere to be found. At the last day when you could revert I decided to check again and the button was there. I am happy to continue this blog. By the way, this blog is best viewed on a computer; you are able to see the details on the photos much better than on a mobile phone. Blogger should understand that not all blogs are written for phones.

The chess board (on the other side) also being a box for the chess pieces.

With the chess pieces complete, it is time to give attention to the making of the board. I decided to make the board into a box, where the chess pieces could safely be stored in. I also prefer light game boards (reason most of our boards are made from poplar), and especially for a relatively heavy chess set, a light box is preferable. So again poplar.

 One half of the board composed of smaller poplar strips. 
The pencil lines show the board squares which align with the glue lines.  

I had some poplar left drying in the workshop. Poplar that was not dry enough when I used it to make a hnfatafl board (the round glass game pieces did not stay put but rolled everywhere on the warped board). I did expect the wood to be dry now, after two extra years in the shop, but to avoid trouble I cut it up into smaller pieces and alternately glued them back together. These smaller pieces had the same with as the squares on the board would be, thus the glue lines would become unnoticeable when the lines were carved.

The half hidden dovetails on the side of the board and the dovetails on the sides of the box.

 The dovetails (test-)fitted together for the box.

Testing if the height of the box is ok for the chess pieces.

Two half game board pieces were made for 6 x 8 squares each. One square approximately 4 cm2, slightly larger than the chess pieces. On three sides an additional edge was added. The sides of the box were connected to the gameboard by half-hidden dovetails. This would also provide extra strength in case of warping. Inside the box, four compartments were made: two small ones for the kings and queens, and two large ones for the remainder of the pieces. The compartments were divided by a thin strip of poplar that was locked inside a groove in the backside of the game board and the sides of the box. The grooves for the squares of the chess board were carved with a carving knife using a metal strip for guidance of the lines.

Left: Glueing the boxparts. Middle and Right: the complete box with and without the chess pieces.

The adapted hinges for the board.

Heating the hinge with a gas torch (left). Note the metal wire that is attached to the hinge 
which was used to quickly drop the red-hot hinge in the linseed oil (right).

Space was chiselled out for the hinges. Two commercially available semi-medieval hinges were bought, but they proved to be too large for the side of the box. These hinges were adapted to a smaller and correct medieval type using cutters, files and a belt sander. Afterwards, the hinges were blacked by heating it with a gas torch and quickly quenching it in linseed oil.

The hare glue (grains) first had to absorb water before they were heated in a glue pot.

The chess board was intended to be luxurious as well, thus half of the squares were gilded, and the other half painted lapis lazuli (I used synthetic lapis lazuli, as the real pigment is far more expensive than the 23.75/24 kt leaf gold used for gilding). An example of such a blue and gold chess board can be found in an illumination in manuscript MS G 24 in the Morgan Library in New York.

Phesonas and Cassiel playing chess on a blue and gold chequered board. Manuscript of Jacques de Longuyon‘s poem 'Les Voeux du Paon', around 1350. Morgan Library, New York, NY, USA, manuscript MS G 24. Folio 025v.

First, the chess box was twice completely covered in hare glue. Then the board and the sides were thrice painted with gesso. For the squares to be gilded this was followed by 3 layers of red bole. Afterwards the bole was polished with steel wool. A gold glue of 3 hours was used to glue the gold leaf to the board. Coincidentally, one gold leaf did just cover a square. Each square was at least gilded twice to provide a stable gold layer.

The board being coated on all sides with hare glue, then several layers of gesso were applied to the sides and top.

  The redbole applied to half of the squares.

Left: Polishing the red bole surface with steel wool. Right: the polished board.

First gold layer added.

Applying gold leaf to the chess board is relatively easy as shown in this video. 
The gold leaf is slightly larger than the square. A second gold layer is being added here.


But then I ran out of gold leaf, and the waiting time for the Siamese gold leaf to arrive was a few months long. It became very warm and dry weather, and despite all the precautions the wood started to warp. So much that the hinges did not fit any more and I had to add some extra wood to the sides to create a flat area again at the hinges side. Furthermore, because of the extra millimetres of wood added, the space for the hinges also had to move a little. The warping on the other side (with all the gilded squares) still exist, but for playing chess this does not matter.

 This photo clearly shows the extra millimetres needed to create a flat surface again.

Left photo: First, the gesso had to be removed from the edges of the box. Then two strips were glued onto the short sides of the box and planed until they were even with the middle of the long side (see also the photo above and below). This was checked with a steel ruler. Right photo: Next, two strips were glued on the long sides. A ruler was used to mark the parts that needed to be planed away to create a flat surface.

The new long side strip being glued. A piece of cloth was used to protect the gold layer on the underside during clamping.

Left: the new flat surface was checked again with a steel ruler. Right: The new flat surface for the hinges of the box. Around 4 mm was added to each side.

Left: Also the space for the hinge needed to move a few millimetres. The remaining space was filled with pieces of wood precisely bended. Temporary nails were used to keep the strips in place during glueing. Right: The wood strips were bend with the heat of a soldering iron clamped to a workbench.

When the box warping was fixed, I still was awaiting the gold leaf. To speed up the process I then decided that I would paint the box first and then apply the second gold layer. I added the black (bone black) and red (Venetian red) colour for the sides, and the lapis lazuli (synthetic ultramarine blue) for the squares. However the drying time of oil-paint can be long, depending on the pigment-oil mixture and the temperature. Now I had the gold leaf, but the paint was still wet and I was unable to finish the gilding. (Actually, I had to order a new set of gold leaf, as the Siamese was of the wrong size. This third package, 24 kt gold, arrived luckily within a week!)

Left: First the sides of the box were painted black and red. When the inside rim was painted, the box was turned and placed on a book - resting on the poplar dividers, so the remaining side and top could be painted. Right: After the back and red, the squares were painted in synthetic lapis lazuli.

At one moment I thought the paint was dry enough to do the gilding. I miscalculated that gold leaf itself can be quite sticky and brushing away the superfluous gold caused it to adhere to the lapis lazuli blue squares. Actually, many lapis lazuli stones have natural gold flakes in them, however lapis lazuli paint does not and should be a bright full ultramarine colour. I had to scratch the gold flakes away with a scalpel from the lapis squares (as well as from the red and black sides). This left all kinds of scratches on the surface, so I had to repaint them.

The second layer of gold being added. The 24 kt gold leaf is much more shiny that the 23.75 kt. Gold leaf does not always stick well to the glue. Sometimes edges are loose and the gold is brushed away. Then a third or even a fourth layer of gold leaf was necessary. These squares needing an extra layer are pointed here with small wooden markers.

Left: Brushing away the excess gold caused the gold flakes to firmly adhere onto the lapis lazuli paint. Right: The gold flakes scraped away, making a second lapis lazuli layer necessary.

Painting the second lapis lazuli layer. You can see the difference between the two board parts: 
the bottom is painted, the top still has the scratched surface.

To avoid the two sides of the board from sticking to each other the lid of small plastic box was used.

Drying the repainted sides of the box, using books and the plastic box lid to stabilize.

Finishing up

Now it was time to fix the hinges with nails as well as add some nails for the 'locking' mechanism. A steel bench block was used to keep the nails against the hinges, while flattening the nails. The inside of the box still was plain poplar wood covered in two layers of hare glue. To protect the chess pieces, I glued a layer of thin red felt on the inside, also with hare glue. A spatula was used to push the felt into the corners of the box.
Left: The nails were bent at the point, and then hammered flat into the wood. Right: a steel bench block - with a piece of wood to set the bench block at the correct height - was used to keep the nails against the hinge while hammering.

The finished hinge.

Left:  Measuring and cutting the felt. Right: Hare glue was added one step at a time 
and the felt was pressed into the corners using a spatula.

The remaining felt pieces were finally cut off with a scizor.

With the box ready, the only the rope and tassel needed to be added for the closing mechanism. The chess board shown in the Vatican Cessolis book used for the chess pieces also has a rope added. Thus a closing mechanism based on a rope and tassel seemed appropriate. The 'rope' was made by de Gelderse Roos in black and red embroidery silk using a miniature rope making machine. There are easy guides on YouTube on how to make a tassel, and I also made use of them.

 The board in the Cessolis manuscript (folio 95r), the rope and tassel marked by the green oval.

The tassel and rope in the red and black colour.

The closed box with the rope alternating between the nails on the box sides.

The complete game

Left: The side of the box showing the hinges. Right: The inside of the box.

The finished courier chess set and board, with the set-up (actually the queen has to stand on the third and sixth row behind the pawn, see the post on playing courier chess).

In the inventory of 1447 of Adolphus, Duke of Guelders  a chess board is mentioned:

Item dat schaeckbret [chess board] mit schaek [chess pieces] ende wortafelspiel [backgammon] as half golt ende silver [half in gold and silver].

Evidently, this is a dual purpose board for both chess and backgammon. This is a quite common combination, also often found with medieval boardgame boxes. Later in the inventory the purchase of a bag for this chess set is mentioned (to protect the board and or chess pieces). The courier chess set is ideally suited for a dual board game purpose as the number of squares on the long side of the board is 12, the same number needed for backgammon. The only extra's needed are a set of dice and three more pawns of each colour (i.e. 15 of each colour). Backgammon then is played only using the pawns as playing pieces.

Two dual purpose boardgame boxes for normal chess and backgammon that were at the auction of 14 July 2020 of Prunier Auction, France. Lot 16: A 15th century certosina-decorated Embriachi box from Venice, Italy. Height 6.3 cm, length 15.7, width 19 cm. Lot 17: Late 15th century Spanish game box. The chess board is on the other side. Height: 4.7 cm, length 25.4 cm, width 17 cm. The lots were sold at 4500 and 3800 Euro (ex auction costs), respectively. Photo copyright Prunier Auction.

The set-up of the courier chess board for backgammon. The folding line of the box neatly divides the board into 4 quarters.

The number of game pieces in courier chess also make it possible to use them for other board games. For instance alquerque needs 12 pawns of each colour, nine men morris needs 9 of each colour, and fox and geese (13 + 2 pawns). The type of game pieces also make it suitable for normal (8x8) and decimal (10x10) chess. It is then only necessary to provide other game boards for these games. 

A three men morris board - needing 3 + 3 pawns for play. 
This small game board was used as a test piece for the courier chess board.


  1. Bravo! Very nice, and i commend you on the gilding. As for lapiz being expensive, more than gold, that was also the case in medieval times. Some things do not change.

    I also agree with your sentiments regarding the blog format. Not everyone uses or wants a "smart-phone"

    As for the warping, i am glad you were able to fix it; i suspect it was caused by the gesso one one side, but not the other. I have found that thin wood wants to have gesso on both sides. (I had a very similar problem) Also, i did a box and used rabbit-skin glue for the fabric lining, only to find out afterwards that the usual glue for fabric in old times is actually made with cooked wheat flour. I mention this because it is 100 times easier to apply the fabric with for your next project.

    Keep up the wonderful projects.


  2. Excellent post. I really like the use of gold leaf. A couple of questions: Did you seal the gold leaf after application? I used 23.75 karat leaf on a project about 5 years ago and 3 years later it had tarnished considerably, although it was protected from normal contact with hands or other things. When redoing it, I sealed it with shellac.

    Second, since this acts as a box for the pieces, have you made a protective bag for the playing surface when the board is not in use?

    Thanks for the great work...