This turned out to be so simple I am ashamed to have asked for help and suggestions.

A previous owner broke off the drive dog retaining bolts - both of them. The only reason I can think of that the drive dogs would have to be removed would be the installation of the power draw bar. Seems the stock drive dogs are short enough that the tool holder can be placed on top of the dogs instead of seated with the dogs in the holder slots. That leaves a couple of draw bar threads to capture the tool holder. Turn it on, move it into the work piece and the tool holder becomes a lethal missile, so longer dogs are part of the power draw bar assembly. With them the draw bar will not reach the tool holder if it is sitting on top of the dogs.

A suggestion was made to use the mill knee to raise a drill bit into the bolt stubs for removal. That suggestion included the the use of a power drill of some kind. After much thinking, I opted to try a fully manual solution. The Jacobs chuck is mounted on a 5/8" straight shank. I mounted a 5C collet in a collet holder on the mill table with the collet just snug enough to hold the shank and still let it rotate. A left handed 1/8" drill bit was picked for the initial hole drilling just in case the bit itself would withdraw the bolt stubs.

The table was gently raised using the hand crank while the drill chuck was turned by hand. The bolt stub came out quite easily.

I used the mill axis drives to set up for the second bolt removal. This included lowering the spindle with the electronic hand wheel to eyeball the alignment on X and Y. "Dummy," says I, "why in the world are you using the mill knee when you can lower the spindle much more easily and a great deal more accurately using the electronic hand wheel?" Not having a ready answer, I decided to do just that.

The hand wheel can be adjusted to .0002" per click, and if that isn't accurate enough, the incremental jog can be adjusted to a single 10th. I moved the hand wheel click up to .002" and proceeded lower the quill with one hand and turn the Jacobs with the other. When I felt the bit grab and the bolt start to turn, I reversed the quill movement and unscrewed the bolt stub.

Here are the culprits along with a new 8x32 replacement bolt. I will knock out some new drive dogs, install them, and the mill will be ready to work.

It is turning out to be a "beast" as described on the previous page, but now seems to be a very "gentle" beast. I've learned to move the table, turn on the spindle, adjust the speed, and run simple programs. It is being tamed, and close to becoming a member of the family.

This job did not require anywhere near the amount of worry I put into it. Very simple, very clean, very neat and very precise. It turned out well.

To those who offered suggestions - my thanks.

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