Making a wheel profile tool - turning the forming tool.

 Now that I had a pair of masters (see here) I could use them to make the forming tools themselves. Like the masters they're made from 16mm dia. silver steel.

The first job was to turn the outside diameter, just to true it up, then with the master tool set to centre height it could be plunged into the rod about 1mm from the front edge until the full form is below the outside diameter of the bar. This is the 2FS tool being formed;

Note the cutting compound, I used the type for tapping and dieing, which I'm not sure was the best choice. The work was turning using the slowest speed possible, and the finish wasn't as good as I'd hoped, the metal tending to tear rather than cut, especially on the wider Code 72 tool. A larger machine would have been a better choice, I felt that I was pushing the Unimat 3 to its limits on this job as far as rigidity was concerned.

I set the toolpost to sit on the right of the saddle whilst doing this, this way all of the force is going straight through the saddle;

When I turned the Code 72 tool I drilled a centre hole and used my rotating centre to help cut down vibration, this was because the code 72 tool is wider than the 2FS one and therefore puts more strain on both the machine and the workpiece;

Once the formers were turned they were both drilled out to 5.1mm, then cut/parted off before being turned to length using a watchmakers step collet leaving 1mm either side of the form;

The next stage followed the same pattern as the master, that is to file out a notch to make a cutting edge, stone the edge until smooth, and then harden and temper both cutters.

Here's a photo of both tools, mounted in the same holders that I used for the master tools.

Now I needed to test them both.

Paul.