FRACTAL MACHINING

In Lightwave 3D 5.6 Applied Dave Jerrard runs through a globe tutorial with the end result looking like this:

Now a close up of the outer support shows this little touch with the use of fractal noise:

Cool eh! - Now on to the nitty gritty - how did Dave do it?:

These are Dave words from the book:

"Normally a surface like this would make the use of a procedural texture nearly impossible, but this surface has an Incline towards the centre, which opens up a couple of possibilities. The first possibility is that we can use that incline to "bend" a procedural texture to follow the curve of the surface.

Click the Bump map button and select Fractal Bumps as the texture. The angle of the polygons on this surface give it a thickness of 4.5mm on the Z axis, which isn't much but a texture map with a small size on the Z axis would appear to stretch outward across the width of this ring. To see this demonstrated give the texture a value of 10mm on the X and Y axis and a much smaller size of 0.01mm on the z axis. Increase the texture amplitude to 100% and click use texture.

Another technique is to apply an image to this surface and have that image bend to conform to this curve as well. In this case we can add a latitude scale, using a simple image, and have the surface bend it around in an arc for use.

Click the texture button for the diffuse channel then click add texture to create a second texture layer. Change this to a cylindrical Image map and then click the texture image button. Load the scale image (horizontal image like a ruler) - Select this as the alpha image and click auto sizing - also activate negative alpha. Then make sure the texture centre values are 0 respectively but leave the Z value alone. Then make the map apply along the z axis.

We now have a scale that wraps around the curved surface although the image is straight and flat."

So how do we apply that to a watch bezel? - - well most watch bezel's are rarely completely flat are they!? <wink>

I've taken the surface - removed the maps changed the colour and applied to a simple bezel with a top taper.

Result number 1 quickly messing about comes up with this - a rough machined finish

next I reduced the texture amplitude to roughly 20% to give a smoother more polished look

Then I messed with the seemingly flat face plate - ensure that the polygons look like this - which is why the lathe operation is the best for things like this:

This way you can raise the central point and thus create an incline to apply a nice Lathed finish to the face and back plate - now because you want the plate to still look relatively flat the point wasn't raised much [0.1 - 0.2mm] and now you have to decrease the fractal bump texture size on the z axis - I took it down to 0.5 nanometre's for that highly polished finished look on the face plate