Feel like I haven't posted any photos for a while probably because I haven't been able to stand up for too long because of the dickey knee.

Anyway things have improved a bit and over the last few days managed to make a 12mm drawbar for the mill and a centre punch centre finder.

I recently purchased an Acute Sharp kit from Eccentric.
It comes as a bunch of fasteners, and precut materials spot drilled which have to be drilled out to size prior to assembly. Watching the accompanying assembly vids and saw Gary's neat little centre finder that is inserted in a mill or drill press enabling accurate position of a workpiece under the chuck. Once the position is established the workpiece is clamped and the finder replaced with the appropriate drill bit.

The parts of the finder are shown in the photo below.
The two main parts are the pointy bit on the right hand side, which I will call the point , and the point holder on the left.

Cfinder.jpg

The spring goes over the shank of the point which then slides into the holder and is held in place by the grub screw that rides in the slot.
To provide further positional stability the 6mm diameter shank of the point slides into a 6 mm diameter hole inside the 12mm shank of the holder.

In the first iteration there was no slot in the point, just a reduce diameter section (R) that together with the grub screw prevented the point from falling out or going back too far.

However, due to various run outs introduced into all the parts all along the way etc when installed in the DP the point wobbled visibly depending on the rotational position of the point so I cut a slot in the point to restrict the rotation and then assembled whole thing and locked the point to the holder with the grub screw.

Then I mounted the the holder shank in the lathe and tuned up the point so that the point so its now concentric with the holder shank.
The run out is thus just run outs from the lathe and the DP and much better than with no slot.

If I was making it again I would not have a reduce diameter section (R).

Works a treat.
Cfinder1.jpg
Attached Images




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