This tutorial will walk you through the steps in making a knife in Photoshop. Please note that there is no singlr way of doing things, and these steps are simply my own way of working, you can experiment with your own style to find easier/better methods. This was created in Photoshop 6.

Thiz tutorial will teach you:
1- Using gradients and the dodge and burn tools to create metallic effects.
2- (almost) Realistic 3d illustration in Photoshop.

Start with a new image, make it wide so that you have room to work because we will be working on the knife horizontally. I started with an image with an 1500 px width and 500 px height.
Make a new layer, call it "edge". Now grab the pen tool, and try to make a shape similar to the one in the pic on the left (press shift when drawing the straight lines, and start at the blunt end to make it easier to draw the tip)

Grab the pen tool again, and try to cut the shape with an outline through the tip as shown.

Close the path, right click and choose "Make selection", then grab the Marquee tool, right click on the selection and choose "Layer via Cut". Call the new layer "blade"

Working on the "edge" layer, make the foreground color light grey (I used 7F7F7F) and the background color even lighter grey ( I used D1CFCF).
Load a selection on the edge layer, grab the gradient tool, using the linear gradient, fill the selection with the gradient from top to bottom as shown.

Hit delete, then move the selection a bit to the right (shift+right arrow 3-4 times), repeat that about 9 times untill you get something similar to this.

Load a selection on the blade layer, fill it with the same gradient from step # but this time from bottom to top, make a black stroke with opacity 60 % using layer styles.

Now time to play with curves.

On the "edge" layer, adjust the curves as shown, or fiddle with it untill the metal effect looks right, switch to the blade layer and adjust the curves to make it very slightly darker than the edge.

When done, link both layers and merge them (Ctrl+E).

Next