Ichthyosaur Fossil

I was asked to provide a prop for a teaching session about Mary Anning (she of "she sells sea shells on the sea shore" fame) what better than an Ichthyosaur fossil, one of her more famous fossil finds.

My fossil will look like a rough edged slab of rock carved out to reveal the bones of the Ichthyosaur.

This is constructed from ply, MDF, doweling and lots of PVA glue.

Step 1: The Design and Template Making

I searched the internet for pictures to work from and sketched out an outline on a couple of sheets of 3mm MDF. This was cut out on my bandsaw and scroll saw, once I was happy with the shape I was ready to start the framework.

Step 2: Construction Begins

The template was traced onto the 2 long narrow pieces of 12mm plywood, a top half and a bottom half for ease of handling and cutting. A third piece of plywood, will become the backing to hold it all together.

Various holes were drilled at the ends of fins and paddles to enable the band saw to turn corners and the cutting out began!

Step 3: Finessing the Shape

Once cut out I used my dremel with a sanding drum to radius the upper edge all around the cut shape.

Step 4: Joining Up

The cut parts were held together with a couple of wooden straps and a rough outline was drawn and cut. This was then glued and screwed to the backing ply and again roughly cut to shape the idea being to make it look as if it was hewn from the living rock.

Step 5: The Bones, Paddles and Head

Referring to pictures previously found on the web I drew the skeleton roughly onto my MDF template and started to cut bones, mainly from MDF but the paddles were cut from hard plastic scored across with a saw disc in my dremel.

The head was made up of layers of 3mm MDF stuck one to the other to give a nice 3D effect.

Step 6: The Bones, Ribs and Spine

The spine is made up from slices of wooden dowel in various sizes interspersed with 3mm MDF shapes, the ribs were cut from 3mm MDF, all of this work was done on my bandsaw.

Step 7: Assembly of Parts 1

The first job was to stick my MDF outline template into the recess to give me a nice flat surface to mount the bones. It was then just a case of placing and gluing lots and lots of little pieces of wood in the right order!

Step 8: Assembly of Parts 2

I split the fossil into sub assemblies, head, middle and tail and as I finished an area I rounded of edges and spray painted to harden off the MDF (MDF goes woolly when it is sanded and can easily be damaged)

Step 9: All Done!

Once all the bones were in place I coated the outer parts with thinned PVA glue and sprinkled it with sand to give a rough rock look, the whole thing was then spray painted and finally varnished.

So that is the wooden model done, next job will be to mould copies in resin, but that is a different instructable ;)