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These are a couple of views of the cutter I made for the dovetail work. It's a 3/8" x 3/4" HSS tool, 4" long. Nice and rigid, which is important because of the odd angles and long tool overhang that's sometimes necessary in dovetail cutting. Most relief and rake angles are about 8 degrees. Since I was cutting 60 degree dovetails, I made the point angle 55 degrees. Big...

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You can see that the butt end of the tool is colored. This is just a copper coating for marking out lines on it. I have much better results grinding a tool this size if I mark it out correctly first. For most markup work I use a Dykem marker, but Dykem doesn't stand up well to the heat of a tool grinding session. I've started dunking unground cutter ends in a solution of copper sulphate for a minute, which puts a copper coating on the steel. This takes the markup lines nicely and holds up pretty well. Big...

The tool in place on the shaper, ready to cut. You can see that in some cases it'll be tough to find room for everything: if you're not careful, the tool slide will stub its toe on the work. To avoid this, you may have to raise the tool slide up away from the work surface, and then extend the tool a good long distance to reach the cut. Times like that, flex and chatter could cause real problems. This is why I used such a heavy piece of HSS to make the cutter. It's a workable solution. The tool slide is set over at 60 degrees, carefully, using a good protractor. The tool is set to leave clearance on both faces of the dovetail being cut. The dovetail is 60 derees and the tool is 55, so there's not a lot of spare room. Note, by the way, that these angles mean that the tool only cuts on its tip, not its edges. Big...

A closeup of the same setup. If you look closely, you can see the scribe line showing where the edge and bottom of the dovetail will be when it's done. Big...

This picture and the next show the tool in the cut and the clearances on both faces being machined. These two shots are very similar, but the former shows the tool well and the latter gives a better view of the work itself. Big...

I didn't set the vise up well: I should have set it around so that the movable jaw was perpendicular to the ram's travel. This would have ensured that the work stayed put rather than being knocked out of the vise by the tool. I didn't bother, and paid for my neglect before the project was through. Big...

The cut itself. The cutter is being lined up to take the next bite out of the growing dovetail. Big...

The cut beginning ... Big...

... and continuing ... Big...

... and almost ending. As you can see, it's a fairly hefty cut. In these pictures I'm using the hand downfeed on the toolslide to accomplish the cut, giving the wheel a little crank during the ram's return stroke. I guess I'm taking about ten thousandths per stroke. Big...

Here I'm using the horizontal power feed to clean up the bottom of the dovetail. Big...

The yellow thing is a glass rod borrowed from my wife's worktable. I held its end up to the freshly cut dovetail to see whether the cast iron would show its reflection. As you can see, it does so pretty well. The finish inside the dovetail is nice and smooth. Big...