1. Carve outline of inlay area
Trace out the area you want to inlay and carve a groove on the inside of this line. I use a Dremel 4000 and cut this groove with a ball burr (carbide or diamond dust works fine). After this groove is cut, go back over the inside edge of your groove with a large cross cut football shaped burr and carve it down so that the inside of the inlay area slopes down to the outside edge of the groove you cut. The idea is that you don’t have to carve down the entire inside of the inlay area just around the edges. Once the snakeskin is put in it will give the illusion that the entire area is sunken but in reality it’s just the edges. Don’t worry about getting the inside area smooth because we will be covering it up with the snake skin. If you are new to carving on skulls and want more information I have a book here that covers everything you need to know.
2. Using paper make template of inlay area
In order to get the right size and shape for the snakeskin you can do the following trick. Take a piece of paper and while holding it in place press down firmly around the entire edge of your space you carved out. This will make a crease/indent in the paper the exact shape and size of your area. You can then cut this shape out and use it as a template to cut out the correct shape of snakeskin. Make sure when you trace out the template on the back of the snakeskin that the scales are pointed in the direction that you want them to be on the skull.
3. Soak snakeskin in water
Now that you have your snakeskin cut out there is one more trick that will make this all work better. Soak the snakeskin in water to make it pliable and drape over the carved out area. Use something like a bag of rice or sand to press down on the skin and form it to the skull and leave it to dry. This will make the skin fit naturally to the contour of the skull when dry.
4. Inlay snakeskin using gel medium
After the skin is dry you can then take this time to trim up any edges that might not fit correctly. The very last step is to bond the skin into the inlay. I use gel medium (it’s actually a gel used to thicken paint but also works great as a bonding agent). Paint a layer of the gel onto the backside on the snakeskin and press into the inlay area. The gel will dry relatively fast so you can press down any edges that might stick up till it dries in place. Then lastly paint on a thin layer of the gel over the entire skin (outside) and edges to further finish and bind the skin in place.
You are left with a very professional clean looking inlay that fits the contour of the skull perfectly, and fits into the inlay correctly using the tips above. When you are looking for snakeskin to use make sure you buy skin that is already tanned and not just stretched out raw and dried. I have found Ebay to be a pretty good resource.