Step 1: Select You Photo
This process will create a stipple portrait onto the surface of the clay. The image is made up of thousands if dots and pops out when light casts a shadow from the raised dots wanted to create a process to put portraits onto clay as I wanted to make a street art tribute to Bowie.
As this an experimental process I’m sure he would have approved. Your file needs to be quite large format this one is 1200×675 and PNG or JPEG format.
Step 2: Get a Stipple Generator Programme
There are lots of stipple generator app for phone but this one is a free desktop version from Evil Mad Scientist called Stipple Generator 2 available from the Evil Mad Scientist website.
Step 3: Stipple Generation Setting and Editing the Image
The Stipple generator website has a great in depth tutorial but for this project there are only are 3 main setting we need to look at.
Once you have launched and uploaded your image you need to set the STIPPLE number field to around the 2000 mark, set your MIN DOT SIZE field to around 5 and DOT SIZE RANGE to 1. This will create a big enough individual dot to cast a shadow and an enough of a range in dot size to add detail to the image.
The image will auto start to populate with dots that will look a mess at first, but don’t worry after the programme has optimised the plotting path about 40 times the image will be a lot clearer. This whole process will only take a 5 minutes. However, if you want to use a higher number of dots then this will considerably slow down the time it takes to optimise the image.
You can then save the image as a JPEG and open it in your favourite editing software and crop the image to the desired size.
Step 4: Making the Mould
There are 2 ways to prepare the press-mould, you can either laser cut as the image above or using a handheld etching tool/drill, this may sound daunting but the hand held drill can be just a quick.
For laser cutting I have found its best to use birch plywood. It requires quite a deep etching, this has had 2 runs with a setting of speed 250 and power of 40.
If you are hand drilling then print out the image and using some spray mount attach the image to the wood. Then using 2 different drill sizes that are the size of the dots drill out each dot down to about 3mm.
Step 5: Pressing the Clay
Roll out a slap of clay to about 10mm. Make the slab bigger than the picture as you can always trim it back later.
Dust the mould with talc to prevent the clay from sticking.
You deed to press the clay into the mould with your fingers or palm of your hand. Rolling the clay with a rolling pin doesn’t work, as this doesn’t push the clay into the dots. You don’t need to push too hard but remember push down not outwards.
Most clays work well on this, porcelain can be a bit sticky, terracotta gives a nice dark finish. If you don’t have access to a kiln then air dried clay also works.
Step 6: The Reveal
Slowly peel the clay off the mould taking care to peel it off and not pull as you can distort the image. You can use any hydrophobic coating (such as waterproof clothing spray) the clay is sticky. Just apply before pressing the clay.
You should then have a reverse image like above.
If you want a true image then just reverse the image at the etching or drilling stage.
You don’t need any special treatment for the kiln you just fire it as you would any other tile.
Step 7: Finishing
Once the tile has been fired you can add thin glaze wash or for this tile I used gold gilding wax.